This work explores the dielectric and electrochemical properties of solid biopolymer blend electrolytes(SBEs)based on a combination of alginate and polyvinyl alcohol(PVA),doped with varying concentrations of ammonium ...This work explores the dielectric and electrochemical properties of solid biopolymer blend electrolytes(SBEs)based on a combination of alginate and polyvinyl alcohol(PVA),doped with varying concentrations of ammonium iodide(NH4I).The SBEs were synthesized using the solution casting method,and their ac conductivity exhibited an optimal value of 1.01×10^(-5) S·cm^(-1) at 25 wt.%NH4I.Detailed dielectric and modulus spectroscopy analyses revealed distinctive trends in relation to NH4I concentration,suggesting complex dielectric relaxation behavior.The universal power law(UPL)analysis identified the Small Polaron Hopping(SPH)mechanism as the dominant conduction process in the optimal sample.These results demonstrate that NH4I-doped alginate-PVA SBEs possess favorable electrochemical properties,positioning them as potential candidates for energy storage and ionic transport devices.展开更多
Synthetic wood adhesives, consisting of urea-formaldehyde resins (UF), phenol-formaldehyde resins (PF), melamine-formaldehyde resins (MF), and polyurethane resins, are widely used. For UF and MF, most investigations a...Synthetic wood adhesives, consisting of urea-formaldehyde resins (UF), phenol-formaldehyde resins (PF), melamine-formaldehyde resins (MF), and polyurethane resins, are widely used. For UF and MF, most investigations are concerned with reducing free formaldehyde content;for PF, most studies focused on finding new alternative chemicals to replace phenol. These adhesives come under the Carcinogenic, Mutagenic, and Reprotoxic chemicals (CMR) category. Due to global energy issues and dependency on petroleum sources, the focus has shifted to look for alternative and renewable raw material sources for wood adhesives. Conventionally available wood adhesives are polyvinyl alcohol (PVA) stabilized, with drawbacks like poor water resistance, poor heat resistance, low-temperature workability, and it’s based on petroleum resources. Polyvinyl acetate (PVAc) is non-resistant to moisture polymer, and if such adhesive joints are exploited in a moist environment, its strength substantially decreases. Sufficiently moisture-resistant adhesive joints are obtained by modifying PVAc dispersion with special compounds like reactive comonomer, Silanes, and modified PVA. To improve the workability at low temperature, Vinyl acetate (VAc) is copolymerized with specific comonomers like butyl acetate without affecting the performance properties. Here, we aim to present an overview of the research trend of PVAc-based adhesives in the wood industry. The review summarizes the current state of research PVAc-based adhesives.展开更多
Increasing global energy crisis and scarcity of petroleum resources has shifted focus of chemical industries to look for alternative raw material resources. The main focus of raw materials in wood adhesives, such as p...Increasing global energy crisis and scarcity of petroleum resources has shifted focus of chemical industries to look for alternative raw material resources. The main focus of raw materials in wood adhesives, such as petroleum and natural gas [1] [2], would be gradually replaced by renewable biopolymers. Starch is a relatively inexpensive and renewable product from abundant plants, easy processing and it has been extensively used as binders, sizing materials, glues and pastes [3], but its bonding capacity is not strong enough to glue wood [4]. Extensive research has been carried out on improving the cohesive properties, especially water resistance, of starch-based adhesives. In starch-based wood adhesive many new approaches have come forward for effective use it in wood/wood composite adhesive giving comparable performance as synthetic adhesives. This review of starch-based adhesives is made with the focus on starch modification methods for improving properties of starch-based adhesives.展开更多
Due to their lower environmental impact, ease of accessibility, low cost, and biodegradability, bio-renewable sources have been used extensively in the last several decades to synthesize adhesives, substituting petroc...Due to their lower environmental impact, ease of accessibility, low cost, and biodegradability, bio-renewable sources have been used extensively in the last several decades to synthesize adhesives, substituting petrochemical-based adhesive. Vegetable oils (including palm, castor, jatropha, and soybean oils), lactic acid, potato starch, and other bio-renewable sources are all excellent sources for the synthesis of adhesives that are being taken into consideration for the synthesis of “eco-friendly” adhesives. Due to their widespread use, accessibility, affordability, and biodegradability, biobased raw materials like carbohydrates used to synthesize wood and wood composite adhesive have gradually replaced petrochemical-based adhesive. Recently, xanthan gum, a naturally occurring polymer, has drawn the interest of scientists as a potentially petroleum source replacement. It possesses specific rheological characteristics, excellent water solubility, and stability to heat, and can be used as a binder, thickener, suspending agent, and stabilizer. Xanthan gum increases the adhesive strength in addition to increasing the viscosity of water-soluble adhesives. This article discusses xanthan gum as a potential substitute for traditional raw materials derived from petroleum that is used as a raw material for adhesives.展开更多
Polyhydroxyalkanoates（PHAs）were synthesized in activated sludge using three types of carbon sources（sodium acetate,sodium propionate and sodium butyrate）,and their characterization were studied.It was shown that t...Polyhydroxyalkanoates（PHAs）were synthesized in activated sludge using three types of carbon sources（sodium acetate,sodium propionate and sodium butyrate）,and their characterization were studied.It was shown that the content of PHA synthesized by microorganisms in activated sludge were different.The biggest synthetic amount up to 36.7% of VSS was obtained when sodium acetate was used as carbon source.The polymer yield was lower when using sodium propionate as the carbon source than when using others,with25.1% of VSS,while resulted in an increase of hydroxyvalerate（HV）units produced.The structure and thermal properties of extracted biopolymers were analyzed by scanning electron microscope（SEM）,Fourier transform infrared spectroscopy（FTIR）and themogravimetry（TG）.展开更多
Leuconostoc spp. （LSland LI1） isolated from sauerkraut and idli batter was selected for dextran production. To enhance the yield of dextran, effects of various parameters such as sucrose concentration, pH, temperatu...Leuconostoc spp. （LSland LI1） isolated from sauerkraut and idli batter was selected for dextran production. To enhance the yield of dextran, effects of various parameters such as sucrose concentration, pH, temperature, incubation and inoculum percentage were analyzed. The optimum sucrose concentration for the Leuconostoc spp. （LS1 and LI1） was found to be 15% and 25% respectively. Isolates produced maximum dextran after 20 h of incubation at 29℃ and the optimum pH was found between 8 and 8.5. The inoculum concentration of 7.5% was more favorable for the production of dextran by Leuconostoc spp. （LS1 and LI1）. The growth kinetic parameters were studied and compared for the strains LS1 and LI1. Mass production of dextran was carried out using a stirred tank batch reactor. FTIR analysis was done to determine the functional groups of dextran, sephadex is prepared by cross linking dextran using epichlorohydrin and the functional groups are determined by FTIR analysis.展开更多
The aim of this study was to formulate drug-loaded bio-lipstrips using novel bioexcipients isolated from the fruit pulp of Litchi chinesis(biomaterial L)and to explore the potentiality of lip skin as a novel translabi...The aim of this study was to formulate drug-loaded bio-lipstrips using novel bioexcipients isolated from the fruit pulp of Litchi chinesis(biomaterial L)and to explore the potentiality of lip skin as a novel translabial drug delivery system.The biomaterial,prepared by a simplified economical process and purified by hot dialysis,was subjected to various physicochemical evaluations along with spectral analysis including UV,FT-IR,Mass and ^(1)H NMR.The lipstrip formulated with the novel bioexcipients was screened for its functional properties,including filmability using a film-casting method,and bio/mucoadhesitivity using a shear-stress method,the Park and Robinson method and a rotating cylinder method.Rosiglitazone-loaded bio-lipstrips were formulated by using biomaterial L as a strip former and dextrose as a flexicizer.The formulated strips were subjected to various evaluations,including thickness,folding endurance,in-vitro release and in-vivo release.The release of rosiglitazone maleate was maintained over 24 h,which was confirmed in in-vitro and in-vivo release experiments.Our results reveal that this biopolymer possesses promising stripability as well as bio-adhesitivity.The formulated bio-lipstrips are feasible for delivering rosiglitazone maleate by translabial administration.展开更多
基金University Malaysia Pahang Al-Sultan Abdullah(UMPSA)under the UMPSA Distinguish Grant(RDU233001)Ministry of Higher Education Malaysia(MOHE)under the FRGS fund(FRGS/1/2023/STG05/UMP/02/2).
文摘This work explores the dielectric and electrochemical properties of solid biopolymer blend electrolytes(SBEs)based on a combination of alginate and polyvinyl alcohol(PVA),doped with varying concentrations of ammonium iodide(NH4I).The SBEs were synthesized using the solution casting method,and their ac conductivity exhibited an optimal value of 1.01×10^(-5) S·cm^(-1) at 25 wt.%NH4I.Detailed dielectric and modulus spectroscopy analyses revealed distinctive trends in relation to NH4I concentration,suggesting complex dielectric relaxation behavior.The universal power law(UPL)analysis identified the Small Polaron Hopping(SPH)mechanism as the dominant conduction process in the optimal sample.These results demonstrate that NH4I-doped alginate-PVA SBEs possess favorable electrochemical properties,positioning them as potential candidates for energy storage and ionic transport devices.
文摘Synthetic wood adhesives, consisting of urea-formaldehyde resins (UF), phenol-formaldehyde resins (PF), melamine-formaldehyde resins (MF), and polyurethane resins, are widely used. For UF and MF, most investigations are concerned with reducing free formaldehyde content;for PF, most studies focused on finding new alternative chemicals to replace phenol. These adhesives come under the Carcinogenic, Mutagenic, and Reprotoxic chemicals (CMR) category. Due to global energy issues and dependency on petroleum sources, the focus has shifted to look for alternative and renewable raw material sources for wood adhesives. Conventionally available wood adhesives are polyvinyl alcohol (PVA) stabilized, with drawbacks like poor water resistance, poor heat resistance, low-temperature workability, and it’s based on petroleum resources. Polyvinyl acetate (PVAc) is non-resistant to moisture polymer, and if such adhesive joints are exploited in a moist environment, its strength substantially decreases. Sufficiently moisture-resistant adhesive joints are obtained by modifying PVAc dispersion with special compounds like reactive comonomer, Silanes, and modified PVA. To improve the workability at low temperature, Vinyl acetate (VAc) is copolymerized with specific comonomers like butyl acetate without affecting the performance properties. Here, we aim to present an overview of the research trend of PVAc-based adhesives in the wood industry. The review summarizes the current state of research PVAc-based adhesives.
文摘Increasing global energy crisis and scarcity of petroleum resources has shifted focus of chemical industries to look for alternative raw material resources. The main focus of raw materials in wood adhesives, such as petroleum and natural gas [1] [2], would be gradually replaced by renewable biopolymers. Starch is a relatively inexpensive and renewable product from abundant plants, easy processing and it has been extensively used as binders, sizing materials, glues and pastes [3], but its bonding capacity is not strong enough to glue wood [4]. Extensive research has been carried out on improving the cohesive properties, especially water resistance, of starch-based adhesives. In starch-based wood adhesive many new approaches have come forward for effective use it in wood/wood composite adhesive giving comparable performance as synthetic adhesives. This review of starch-based adhesives is made with the focus on starch modification methods for improving properties of starch-based adhesives.
文摘Due to their lower environmental impact, ease of accessibility, low cost, and biodegradability, bio-renewable sources have been used extensively in the last several decades to synthesize adhesives, substituting petrochemical-based adhesive. Vegetable oils (including palm, castor, jatropha, and soybean oils), lactic acid, potato starch, and other bio-renewable sources are all excellent sources for the synthesis of adhesives that are being taken into consideration for the synthesis of “eco-friendly” adhesives. Due to their widespread use, accessibility, affordability, and biodegradability, biobased raw materials like carbohydrates used to synthesize wood and wood composite adhesive have gradually replaced petrochemical-based adhesive. Recently, xanthan gum, a naturally occurring polymer, has drawn the interest of scientists as a potentially petroleum source replacement. It possesses specific rheological characteristics, excellent water solubility, and stability to heat, and can be used as a binder, thickener, suspending agent, and stabilizer. Xanthan gum increases the adhesive strength in addition to increasing the viscosity of water-soluble adhesives. This article discusses xanthan gum as a potential substitute for traditional raw materials derived from petroleum that is used as a raw material for adhesives.
基金Supported by the National Science&Technology Pillar Program During the 12th Five-Year Plan Period(2014BAC28B01)Beijing Natural Science Foundation(8112012)
文摘Polyhydroxyalkanoates（PHAs）were synthesized in activated sludge using three types of carbon sources（sodium acetate,sodium propionate and sodium butyrate）,and their characterization were studied.It was shown that the content of PHA synthesized by microorganisms in activated sludge were different.The biggest synthetic amount up to 36.7% of VSS was obtained when sodium acetate was used as carbon source.The polymer yield was lower when using sodium propionate as the carbon source than when using others,with25.1% of VSS,while resulted in an increase of hydroxyvalerate（HV）units produced.The structure and thermal properties of extracted biopolymers were analyzed by scanning electron microscope（SEM）,Fourier transform infrared spectroscopy（FTIR）and themogravimetry（TG）.
文摘Leuconostoc spp. （LSland LI1） isolated from sauerkraut and idli batter was selected for dextran production. To enhance the yield of dextran, effects of various parameters such as sucrose concentration, pH, temperature, incubation and inoculum percentage were analyzed. The optimum sucrose concentration for the Leuconostoc spp. （LS1 and LI1） was found to be 15% and 25% respectively. Isolates produced maximum dextran after 20 h of incubation at 29℃ and the optimum pH was found between 8 and 8.5. The inoculum concentration of 7.5% was more favorable for the production of dextran by Leuconostoc spp. （LS1 and LI1）. The growth kinetic parameters were studied and compared for the strains LS1 and LI1. Mass production of dextran was carried out using a stirred tank batch reactor. FTIR analysis was done to determine the functional groups of dextran, sephadex is prepared by cross linking dextran using epichlorohydrin and the functional groups are determined by FTIR analysis.
文摘The aim of this study was to formulate drug-loaded bio-lipstrips using novel bioexcipients isolated from the fruit pulp of Litchi chinesis(biomaterial L)and to explore the potentiality of lip skin as a novel translabial drug delivery system.The biomaterial,prepared by a simplified economical process and purified by hot dialysis,was subjected to various physicochemical evaluations along with spectral analysis including UV,FT-IR,Mass and ^(1)H NMR.The lipstrip formulated with the novel bioexcipients was screened for its functional properties,including filmability using a film-casting method,and bio/mucoadhesitivity using a shear-stress method,the Park and Robinson method and a rotating cylinder method.Rosiglitazone-loaded bio-lipstrips were formulated by using biomaterial L as a strip former and dextrose as a flexicizer.The formulated strips were subjected to various evaluations,including thickness,folding endurance,in-vitro release and in-vivo release.The release of rosiglitazone maleate was maintained over 24 h,which was confirmed in in-vitro and in-vivo release experiments.Our results reveal that this biopolymer possesses promising stripability as well as bio-adhesitivity.The formulated bio-lipstrips are feasible for delivering rosiglitazone maleate by translabial administration.
