This article aims to present the feasibility of storing thermal energy in buildings for solar water heating while maintaining the comfort environment for residential buildings.Our contribution is the creation of insul...This article aims to present the feasibility of storing thermal energy in buildings for solar water heating while maintaining the comfort environment for residential buildings.Our contribution is the creation of insulating composite panels made of bio-based phase change materials(bio-PCM is all from coconut oil),cement and renewable materials(treated wood fiber and organic clay).The inclusion of wood fibers improved the thermal properties;a simple 2%increase of wood fiber decreased the heat conductivity by approximately 23.42%.The issues of bio-PCM leakage in the cement mortar and a roughly 56.5%reduction in thermal conductivity with bio-PCM stability in composite panels can be resolved by treating wood fibers with an adjuvant by impregnating them in bio-PCM in the presence of the treated clay generated.Clay and wood fiber were treated with adjuvants that are both biological and environmentally acceptable,as confirmed by FTIR spectroscopy.The heat transfer bench(DIDATEK)showed a decrease in thermal conductivity.By using differential scanning calorimetric(DSC)analysis,the investigation of thermal stability and enthalpy during two heating cycles of pure bio-PCM and composite bio-PCM was validated.The novel renewable material was used to create composite panels for the trial prototype,which took the shape of a component attached to the solar heating system,33.57%less heat was lost,according to the heat transfer research.The outcomes demonstrated the possibility of replacing traditional electric water heating in residential buildings with solar water heating systems.展开更多
The objective of this study is to analyze the effects of using surfactant(CTAB)and cellulose nanofibers(NFC)as an admixture in cement mortars.We examined composite properties as porosity,compression energy,thermal con...The objective of this study is to analyze the effects of using surfactant(CTAB)and cellulose nanofibers(NFC)as an admixture in cement mortars.We examined composite properties as porosity,compression energy,thermal conductivity and hydration.The results showed that with the addition of 0.7%by weight of NFC per emulsion in the presence of a cationic surfactant(CTAB).The new material produced presented a dry porosity between 4.7%and 4.4%,compressive strength between 9.8 and 22.9 MPa,and thermal conductivity between 0.95 and 2.25 W·m^(−1)·K^(−1).Thus we show better mechanical and thermal performance than that traditional Portland cement mortar with a density similar.In addition,the mortar made by emulsion of ordinary portland cement,cellulose nanofiber and organophilic clay(OC)treated with cetyltrimethylammonium bromide(CTAB)obtained has good resistance under high temperature and water,as well as excellent thermal insulation performance under high temperature and humidity conditions.This study verified that the presence of NFC promotes hydration,leading to the production of more calcium silicate and portlandite gel.展开更多
Nanofibrillated wood fiber was used as fillers in the partial cement matrix replacing the cement to a content of up to 2%by weight of cement.The nanofibrillated effect of wood fibers on porosity,thermal properties and...Nanofibrillated wood fiber was used as fillers in the partial cement matrix replacing the cement to a content of up to 2%by weight of cement.The nanofibrillated effect of wood fibers on porosity,thermal properties and compressive strength was studied.The results obtained showed an improvement in compressive strength of more than 40%with 1%by weight of wood fiber nanofibrillate.The addition of nanofibrillated wood fiber shows a good pore reduction,and the best result was obtained with emulsion of a mixture incorporating 1%by weight of wood fiber nanofibrillate in the presence of an anionic surfactant(SDBS).Thermal conductivity measurements and thermal expansion coefficient,compared to nanofibrillated wood fiber reinforced cement pastes,showed the reinforcing efficiency of cellulose fiber nanofibrillate.The degree of hydration of the cement increased with nanofibrillated wood fibers.This property has been confirmed by Fourier transform infrared spectroscopy.These analyzes revealed that the presence of nanofibrillated wood fibers generates and promotes the hydration of the cement,producing more portlandite and calcium silicate gel,which influences the compressive strength which gives a strong improvement.展开更多
Wood nanofibers from industrial waste have been used as polymeric material to reinforce the cement paste to a content of up to 2%by weight of cement.The effect of the wood nanofibre content on the porosity,the compres...Wood nanofibers from industrial waste have been used as polymeric material to reinforce the cement paste to a content of up to 2%by weight of cement.The effect of the wood nanofibre content on the porosity,the compressive strength and the degree of hydration of the cement was studied.The results showed an improvement in compressive strength of over 50%with 1%of added fiberwood.Chemical modification of nanofiber wood by grafting alkyl chains to their surface can reduce the amount of water absorbed by the sample.Addition of an anionic additive(SDBS)to the mixing water improves the surface of the samples more and more by minimizing the pore size by emulsion effect,hence the water absorption decreases.The degree of hydration of the cement increased with the cellulose content containing nanofibrils.The analysis revealed that the presence of nanofibers favored the hydration of the cement by producing more calcium silicate gel and portlandite,probably the main reason for this improvement in compressive strength.展开更多
Chemical preparation, X-ray single-crystal, thermal behavior, and IR spectroscopy investigations are given for a new organic cation dihydrogenomonophosphate (C7H9N2O)H2PO4 (denoted ABHP) in the solid state. This compo...Chemical preparation, X-ray single-crystal, thermal behavior, and IR spectroscopy investigations are given for a new organic cation dihydrogenomonophosphate (C7H9N2O)H2PO4 (denoted ABHP) in the solid state. This compound crystallizes in the monoclinic space group P21/n. The unit cell dimensions are: a = 11.011(5) Å, b = 5.861(1) Å, c = 15.944(4) Å and β = 100.81(5) with V = 1010.7(6) Å3 and Z = 4. The structure has been solved using direct method and refined to a reliability R factor of 0.048. The atomic arrangement can be described as inorganic clusters [H4P2O8]2- anions between which are located the organic dimmers (C14H18N4O2)2+ through multiple hydrogen bonds (Figure 1)展开更多
Single crystals of the 4,4’-diamoniumdiphenylmethan sulfate hydrate, denoted DDPS, were grown by slow evaporation solution technique at room temperature. The compound was characterized by single crystal X-ray diffrac...Single crystals of the 4,4’-diamoniumdiphenylmethan sulfate hydrate, denoted DDPS, were grown by slow evaporation solution technique at room temperature. The compound was characterized by single crystal X-ray diffraction, IR and thermal analysis (TG-DTA). It crystallizes in the monoclinic system (space group C2/c) with the following unit cell dimensions: a = 17.7635(10) ?, b = 9.3796(10) ?, c = 27.5676(10) ?, β = 97.37(2)°, V = 4555.2(6) ?. The structure was solved by the direct method and refined to final R value of 0.0472 for 2108 independent reflections. The anions are hydrogen bonded to each other, forming clusters [HS2O8]3﹣ parallel to the plan (a, b). The water molecules connect these clusters via O-H···O hydrogen bonds. The organic cations are attached to the clusters through N-H···O hydrogen bonds, forming an infinite three-dimensional network.展开更多
文摘This article aims to present the feasibility of storing thermal energy in buildings for solar water heating while maintaining the comfort environment for residential buildings.Our contribution is the creation of insulating composite panels made of bio-based phase change materials(bio-PCM is all from coconut oil),cement and renewable materials(treated wood fiber and organic clay).The inclusion of wood fibers improved the thermal properties;a simple 2%increase of wood fiber decreased the heat conductivity by approximately 23.42%.The issues of bio-PCM leakage in the cement mortar and a roughly 56.5%reduction in thermal conductivity with bio-PCM stability in composite panels can be resolved by treating wood fibers with an adjuvant by impregnating them in bio-PCM in the presence of the treated clay generated.Clay and wood fiber were treated with adjuvants that are both biological and environmentally acceptable,as confirmed by FTIR spectroscopy.The heat transfer bench(DIDATEK)showed a decrease in thermal conductivity.By using differential scanning calorimetric(DSC)analysis,the investigation of thermal stability and enthalpy during two heating cycles of pure bio-PCM and composite bio-PCM was validated.The novel renewable material was used to create composite panels for the trial prototype,which took the shape of a component attached to the solar heating system,33.57%less heat was lost,according to the heat transfer research.The outcomes demonstrated the possibility of replacing traditional electric water heating in residential buildings with solar water heating systems.
文摘The objective of this study is to analyze the effects of using surfactant(CTAB)and cellulose nanofibers(NFC)as an admixture in cement mortars.We examined composite properties as porosity,compression energy,thermal conductivity and hydration.The results showed that with the addition of 0.7%by weight of NFC per emulsion in the presence of a cationic surfactant(CTAB).The new material produced presented a dry porosity between 4.7%and 4.4%,compressive strength between 9.8 and 22.9 MPa,and thermal conductivity between 0.95 and 2.25 W·m^(−1)·K^(−1).Thus we show better mechanical and thermal performance than that traditional Portland cement mortar with a density similar.In addition,the mortar made by emulsion of ordinary portland cement,cellulose nanofiber and organophilic clay(OC)treated with cetyltrimethylammonium bromide(CTAB)obtained has good resistance under high temperature and water,as well as excellent thermal insulation performance under high temperature and humidity conditions.This study verified that the presence of NFC promotes hydration,leading to the production of more calcium silicate and portlandite gel.
文摘Nanofibrillated wood fiber was used as fillers in the partial cement matrix replacing the cement to a content of up to 2%by weight of cement.The nanofibrillated effect of wood fibers on porosity,thermal properties and compressive strength was studied.The results obtained showed an improvement in compressive strength of more than 40%with 1%by weight of wood fiber nanofibrillate.The addition of nanofibrillated wood fiber shows a good pore reduction,and the best result was obtained with emulsion of a mixture incorporating 1%by weight of wood fiber nanofibrillate in the presence of an anionic surfactant(SDBS).Thermal conductivity measurements and thermal expansion coefficient,compared to nanofibrillated wood fiber reinforced cement pastes,showed the reinforcing efficiency of cellulose fiber nanofibrillate.The degree of hydration of the cement increased with nanofibrillated wood fibers.This property has been confirmed by Fourier transform infrared spectroscopy.These analyzes revealed that the presence of nanofibrillated wood fibers generates and promotes the hydration of the cement,producing more portlandite and calcium silicate gel,which influences the compressive strength which gives a strong improvement.
文摘Wood nanofibers from industrial waste have been used as polymeric material to reinforce the cement paste to a content of up to 2%by weight of cement.The effect of the wood nanofibre content on the porosity,the compressive strength and the degree of hydration of the cement was studied.The results showed an improvement in compressive strength of over 50%with 1%of added fiberwood.Chemical modification of nanofiber wood by grafting alkyl chains to their surface can reduce the amount of water absorbed by the sample.Addition of an anionic additive(SDBS)to the mixing water improves the surface of the samples more and more by minimizing the pore size by emulsion effect,hence the water absorption decreases.The degree of hydration of the cement increased with the cellulose content containing nanofibrils.The analysis revealed that the presence of nanofibers favored the hydration of the cement by producing more calcium silicate gel and portlandite,probably the main reason for this improvement in compressive strength.
文摘Chemical preparation, X-ray single-crystal, thermal behavior, and IR spectroscopy investigations are given for a new organic cation dihydrogenomonophosphate (C7H9N2O)H2PO4 (denoted ABHP) in the solid state. This compound crystallizes in the monoclinic space group P21/n. The unit cell dimensions are: a = 11.011(5) Å, b = 5.861(1) Å, c = 15.944(4) Å and β = 100.81(5) with V = 1010.7(6) Å3 and Z = 4. The structure has been solved using direct method and refined to a reliability R factor of 0.048. The atomic arrangement can be described as inorganic clusters [H4P2O8]2- anions between which are located the organic dimmers (C14H18N4O2)2+ through multiple hydrogen bonds (Figure 1)
文摘Single crystals of the 4,4’-diamoniumdiphenylmethan sulfate hydrate, denoted DDPS, were grown by slow evaporation solution technique at room temperature. The compound was characterized by single crystal X-ray diffraction, IR and thermal analysis (TG-DTA). It crystallizes in the monoclinic system (space group C2/c) with the following unit cell dimensions: a = 17.7635(10) ?, b = 9.3796(10) ?, c = 27.5676(10) ?, β = 97.37(2)°, V = 4555.2(6) ?. The structure was solved by the direct method and refined to final R value of 0.0472 for 2108 independent reflections. The anions are hydrogen bonded to each other, forming clusters [HS2O8]3﹣ parallel to the plan (a, b). The water molecules connect these clusters via O-H···O hydrogen bonds. The organic cations are attached to the clusters through N-H···O hydrogen bonds, forming an infinite three-dimensional network.
