In this study,composite films consisting of polylactic acid(PLA),ethyl cellulose(EC),and zein were prepared by solution casting method,and their performance and application in chilled fresh meat preservation were inve...In this study,composite films consisting of polylactic acid(PLA),ethyl cellulose(EC),and zein were prepared by solution casting method,and their performance and application in chilled fresh meat preservation were investigated.The results showed that the three materials had satisfactory compatibility in the composite film.Addition of EC and zein effectively improved the mechanical properties,thermodynamic properties,surface hydrophilicity,oxygen permeability,and degradation properties of PLA films.When the ratio of PLA to EC was 3:7,the tensile strength and elongation at break reached maximum values of 16.6 MPa and 30.5%,respectively.Moreover,under different conditions,the composite film exhibited better degradability than the PLA film.The composite film with a 3:7 ratio of PLA to EC had the best performance,with a degradation rate of 21.75%after 84 days.Chilled fresh meat wrapped with the composite film showed significantly improved antioxidant,antibacterial,and water-holding properties.展开更多
The kinetics of reductive leaching of manganese from a low-grade manganese oxide ore were studied using cellulose as reductant in dilute sulfuric acid medium.It was found that when the stirring speed was higher than 2...The kinetics of reductive leaching of manganese from a low-grade manganese oxide ore were studied using cellulose as reductant in dilute sulfuric acid medium.It was found that when the stirring speed was higher than 200 r/min,the effect of gas film diffusion on manganese extraction efficiency could be neglected,and the kinetic behavior was investigated under the condition of elimination of external diffusion influence on the leaching process.Effects of leaching temperature,mass ratio of cellulose and ore,and the sulfuric acid concentration on manganese extraction efficiency were discussed.The kinetic data were analyzed based on the shrinking core model,which indicated that the leaching process was dominated by both ash layer diffusion and chemical reaction at the initial stage,with the progress of leaching reaction,the rate-controlling step switched to the ash layer diffusion.It was also concluded that the sulfuric acid concentration had the most significant influence on the leaching rate,the reaction orders with respect to the sulfuric acid concentration were 2.102 in the first 60 min,and 3.642 in the later 90 min,while the reaction orders for mass ratio of cellulose and ore were 0.660 and 0.724,respectively.An Arrhenius relationship was used to relate the temperature to the rate of leaching,from which apparent activation energies were calculated to be 46.487 kJ/mol and 62.290 kJ/mol at the two stages,respectively.Finally,the overall leaching rate equations for the manganese dissolution reaction with cellulose in sulphuric acid solution were developed.The morphological changes and mineralogical forms of the ore before and after the chemical treatment were discussed with the support of SEM and XRD analyses.展开更多
Carboxylmethyl cellulose(CMC) has become a commercial organic binder in agglomeration of iron ore concentrates. The relative molecular mass and degree of substitution(DS) of CMC have a large impact on its binding perf...Carboxylmethyl cellulose(CMC) has become a commercial organic binder in agglomeration of iron ore concentrates. The relative molecular mass and degree of substitution(DS) of CMC have a large impact on its binding performance. The interaction mechanism between CMC and iron ore particles was analyzed through Zeta potential measurements, adsorption measurements and infrared spectra. The results show that the interaction is chemical adsorption-oriented and the CMC's adsorption performance is related to the properties of CMC as well as the type of iron oxides. CMC has a greater affinity to Fe2O3 than Fe3O4, and CMC with higher relative molecular mass shows a higher adsorption isotherm. Pelletization of practical iron ore concentrates added with CMC further illustrates that CMC with higher relative molecular mass or DS exhibits a better binding performance, which is consistent with the results of adsorption tests.展开更多
Bacillus subtilis is a representative probiotic widely used in food, medicine, livestock and other industries. In this experiment a strain of Bacillus subtilis was isolated and identified, and its ability to degrade c...Bacillus subtilis is a representative probiotic widely used in food, medicine, livestock and other industries. In this experiment a strain of Bacillus subtilis was isolated and identified, and its ability to degrade cellulose was also measured. The results showed that Bacillus subtilis had strong capacity to degrade cellulose(62.3% was degraded) and weak capacity to degrade hemicellulose(17.2% was degraded), while it could hardly degrade lignin. The total protein amount in the fermentation medium with cellulose-rich substrate reached by 9.4% after Bacillus subtilis fermentation, compared with that without cellulose-rich substrate. Furthermore, the amounts of Met, Lys and Leu reached by 31.4%, 42.2% and 4.9%, respectively. At 36 h of fermentation, the activity of cellulase reached the highest, and at this time the activity of the enzyme was obtained at 7.19 U · mL-1. The mRNA expression level of the cellulase gene was detected by qPCR, and the experimental group with cellulose substrate was about 2.5 times more than that of the non-cellulose substrate control group. These above results demonstrated that this strain of Bacillus subtilis had a strong ability to degrade cellulose, and synthesize more proteins and restrictive essential amino acids. This study revealed that Bacillus subtilis was a new alternative to ferment cellulose substrates to produce commercial feed or feed additives.展开更多
This review paper explores the potential of oil palm biomass as a valuable cellulose source for the production of nitrocellulose-based propellants,contributing to the green revolution and sustainable energy solutions....This review paper explores the potential of oil palm biomass as a valuable cellulose source for the production of nitrocellulose-based propellants,contributing to the green revolution and sustainable energy solutions.It highlights the availability of the corresponding biomass in Malaysia and in line with global studies,the chemical compositions,as well as a brief description of current technologies for converting biomass of oil palm into value added products specifically cellulose.Steps to achieve maximum utilization of biomass from oil palm industry for cellulose production and prospective source for nitrocellulose-based propellant are also proposed.The methodology section outlines the pretreatment of lignocellulosic fibres,cellulose extraction,and nitrocellulose production processes.Overall,the review underscores the prospective of palm oil biomass as a sustainable cellulose source for propellant manufacturing,while acknowledging the need for further research and advancements in the field.展开更多
The design of astonishing combinations of benzoxazine resins with various fillers is nowadays of great interest for high quality products,especially in ballistic armors.The objective of this study is to investigate a ...The design of astonishing combinations of benzoxazine resins with various fillers is nowadays of great interest for high quality products,especially in ballistic armors.The objective of this study is to investigate a new hybrid material prepared as multi-layered composite plate by hand lay-up technique.Different composites were manufactured from Kevlar fabrics reinforced polybenzoxazine,which was filled with silane treated microcrystalline cellulose(MCC Si)at various amounts in the interlayers.The developed materials were tested for their flexural,dynamic mechanical and ballistic performance.The aim was to highlight the effect of adding different amounts of MCC Si on the behavior of the different plates.Compared to the baseline,the dynamic mechanical and bending tests revealed an obvious decrease of the glass transition of 21℃and a notable increase in storage modulus and flexural strength of about 180%and17%,respectively,upon adding 1%MMC Si as filler.Similarly,the ballistic test exhibited an enhancement in kinetic energy absorption for which the composite supplemented with 1%MCC Si had the maximal energy absorption of 166.60 J.These results indicated that the developed panels,with interesting mechanical and ballistic features,are suitable to be employed as raw materials to produce body armor.展开更多
Objective This work is designed to fabricate a new low density lipoprotein(LDL)absorbent through a mussel-inspired approach and to evaluate the blood compatibility and adsorption clearance,capacity and selectivity of ...Objective This work is designed to fabricate a new low density lipoprotein(LDL)absorbent through a mussel-inspired approach and to evaluate the blood compatibility and adsorption clearance,capacity and selectivity of this technique in vitro.Methods Heparin immobilized cellulose(HeTaCe)hydrogels were fabricated through a mussel-inspired approach.Fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,thermo gravimetric analysis were used to characterize the chemical compositions of the hydrogels.展开更多
The purpose of the experiment is to research the effect of different rapeseed treatments feeding on activity of cellulose enzyme in sheep. Eight male adults of semi-fine wool sheep breeds with the same weight and perm...The purpose of the experiment is to research the effect of different rapeseed treatments feeding on activity of cellulose enzyme in sheep. Eight male adults of semi-fine wool sheep breeds with the same weight and permanent rurnen cannulas were selected according to 4×4 Latin square design to determine the effect of different rapeseed treatment groups including crushed rapeseed, whole rapeseed, extruded rapeseed （dietary lipid content of =67 g·kg^-1） and control group （dietary lipid content of =30 g·kg^-1） on activity dynamic variation of ruminal celluolytic enzyme in sheep. The results showed that ruminal fluid pH matched up to the condition of fiber degradation and growth of cellulolytic bacterium when fed four diets; but there was significant difference （P〈0.05） for the activity of microcrystalline cellulose, glucanase, salicin enzyme involved in ruminal fiber degradation after fed 2, 4, 6 h.展开更多
Bacillus lincheniformis is a representative probiotic, widely used in food, medicine and livestock industries and other industries. In this experiment, a strain of Bacillus lincheniformis was isolated and identified, ...Bacillus lincheniformis is a representative probiotic, widely used in food, medicine and livestock industries and other industries. In this experiment, a strain of Bacillus lincheniformis was isolated and identified, which was used to ferment celluloserich substrate. The effects were analyzed. The experimental results showed that Bacillus lincheniformis had the capacity to degrade cellulose(32.8% was degraded) and less capacity to degrade hemicellulose(7.9% was degraded), which could not degrade ligin. The total protein contents in the products fermented by Bacillus lincheniformis with cellulose-rich substrate riched by 11.6%, compared with the fermented products with no cellulose-rich substrate, furthermore, the contents of Met, Lys and Leu riched by 14%, 17.5% and 4.1%, respectively. These results showed that Bacillus lincheniformis had the ability to degrade cellulose and it provided experimental data for further utilization.展开更多
The mechanistic basis of cellulose biosynthesis in plants has gained ground during last decade or so.The isolation of plant cDNA clones encoding cotton homologs of the bacterial cellulose
The effect of solution conditions on the depression of chlorite using CMC (carboxymethyl cellulose) as depressant was studied through flotation tests and adsorption measurements. Flotation and adsorption tests were fi...The effect of solution conditions on the depression of chlorite using CMC (carboxymethyl cellulose) as depressant was studied through flotation tests and adsorption measurements. Flotation and adsorption tests were first studied as a function of initial solution conditions. The results show that electrostatic repulsion between CMC molecules and chlorite surface hinders the approach of the CMC molecules to the chlorite surface and CMC adsorbs to a great extent at high ionic concentration (10-4 mol/L ions as opposed to 0 mol/L ions) or low pH (3 as opposed to 9). The enhanced adsorption density is attributed to the decreased electrostatic repulsion between CMC and mineral surface. The solution condition that yielded the lowest initial adsorbed amount (0 mol/L ions, pH 9) was used as a reference to investigate the response of the adsorbed CMC layer to a switch in solution conditions after adsorption. The two kinds of solution switches (reducing the solution pH or increasing ionic concentration) result in an increased depression effect of CMC on chlorite flotation, as a result of conformational change of CMC pre-adsorbed layer. The change in the flotation recovery of the CMC-coated chlorite following the solution switches is reversible.展开更多
Cellulose synthesis could play an important rolein determining certain aspects of cotton fiberquality,and despite it’s abundance in nature,little is known about the biosynthesis of thispolymer.Recent advances in unde...Cellulose synthesis could play an important rolein determining certain aspects of cotton fiberquality,and despite it’s abundance in nature,little is known about the biosynthesis of thispolymer.Recent advances in understanding thesynthesis of cellulose come from the analysis ofArabidopsis thaliana cellulose-deficient mutants,and the isolation of a number of genes展开更多
The spherical macroporous cellulose(SMC) was fabricated using medical absorbent cotton as raw material and nano CaCO3 as porogenic agents.And then,the phenylglycine was grafted onto the SMC to obtain the novel spheric...The spherical macroporous cellulose(SMC) was fabricated using medical absorbent cotton as raw material and nano CaCO3 as porogenic agents.And then,the phenylglycine was grafted onto the SMC to obtain the novel spherical macroporous cellulose derivative adsorbent(PSMC).FT-IR and scanning electron microscope(SEM) were employed to characterize the adsorbents and Fe3+ ions served as model solute to evaluate the adsorption property of the adsorbents.The experimental results show that the amount of porogenic agents and the value of pH have obvious influence on adsorption capacity of the adsorbents.The data of adsorption kinetic and isotherm display that the adsorbents possess excellent equilibrium adsorption capacity(348.94 mg/g) and have a bright prospect and considerable potential in the treatment of Fe3+ ions in wastewater.展开更多
A sustainable process was explored for the preparation of 5-hydroxymethylfurfural(HMF) by catalytic degradation of the waste cotton stalk. Solid super-acid(SO_4^(2-)/ZrO_2) was used as an efficient catalyst for the de...A sustainable process was explored for the preparation of 5-hydroxymethylfurfural(HMF) by catalytic degradation of the waste cotton stalk. Solid super-acid(SO_4^(2-)/ZrO_2) was used as an efficient catalyst for the degradation of cotton stalk. Both decomposition experiments and kinetic study were conducted for the exploration of degradation condition and kinetics mechanism. The optimized experimental conditions are reaction temperature 503 K, reaction time 75 min and dosage of catalyst 30%(mass fraction) based on the decomposition experiments, under which a maximum yield of 27.2% for HMF could be achieved. Kinetic study was then carried out in the presence of SO_4^(2-)/ZrO_2. The theoretical results indicate that the activation energies for reducing sugar and HMF with catalyst are 96.71 k J/mol, 84.21 kJ/mol in the presence of SO_4^(2-)/ZrO_2, and they are 105.96 k J/mol and 119.37 k J/mol in the absence of SO_4^(2-)/ZrO_2.展开更多
Background:The majority of attenuated total reflection Fourier transform infrared(ATR FT-IR)investigations of cotton are focused on the fiber tissue for biological mechanisms and understanding of fiber development and...Background:The majority of attenuated total reflection Fourier transform infrared(ATR FT-IR)investigations of cotton are focused on the fiber tissue for biological mechanisms and understanding of fiber development and maturity,but rarely on other cotton biomass comp on ents.This work examined in detail the ATR FT-IR spectral features of various cott on tissues/organs at reproductive and maturation stages,an a lyzed and discussed their biological implications.Results:The ATR FT-IR spectra of these tissues/organs were an a lyzed and compared with the focus on the lower wavenumber fingerprinting range.Six outstanding FT-IR bands at 1730,1620,1525,1235,1050 and 895 cm^(-1) represented the major C=O stretching,protein Amide I,Amide II,the O-H/N-H deformation,the total C-O-C stretching and the β-glycosidic linkage in celluloses,respectively,and impacted differently between these organs with the two growth stages.Furthermore,the band intensity at 1620,1525,1235,and 1050 cm^(-1) were exclusively and significantly correlated to the levels of protein(Amide I bond),protein(Amide II bond),cellulose,and hemicellulose,respectively,whereas the band at 1730 cm^(-1) was negatively correlated with ash content.Conclusions:The resulting observations indicated the capability of ATR FT-IR spectroscopy for monitoring changes,transportation,and accumulation of the major chemical components in these tissues over the cotton growth period.In other words,this spectral technology could be an effective tool for physiological,biochemical,and morphological research related to cotton biology and development.展开更多
In this research,a promising class of insensitive and high-energy dense biopolymers,which contain nitrogen-rich 1H-tetrazol-1-yl acetate and nitrate ester functional groups,was successfully synthesized through tetrazo...In this research,a promising class of insensitive and high-energy dense biopolymers,which contain nitrogen-rich 1H-tetrazol-1-yl acetate and nitrate ester functional groups,was successfully synthesized through tetrazole derivatization and nitration of cellulose and its micro-sized derivative(TNCN and TCMCN).Their molecular structures,physicochemical properties,thermal behaviors,mechanical sensitivities and detonation performances were studied and compared to those of the corresponding nitrocellulose and nitrated micro-sized cellulose(NCN and CMCN).The developed energetic TNCN and TCMCN exhibited insensitive character with excellent features such as density of 1.710 g/cm3and 1.726 g/cm3,nitrogen content of 20.95%and 22.59%,and detonation velocity of 7552 m/s and 7786 m/s,respectively,and thereby demonstrate their potential applications as new generation of energetic biopolymers to substitute the common NCN.Furthermore,thermal results showed that the designed nitrated and chemical modified cellulosic biopolymers displayed good thermal stability with multistep decomposition mechanism.These results enrich future prospects for the design of promising insensitive and high-energy dense cellulose-rich materials and commence a new chapter in this field.展开更多
Cotton fiber growth consists of four overlappingdevelopmental stages:fiber initiation,cellelongation,secondary wall deposition andmaturation.To date,great progresses have beenmade on cellulose synthesis and deposition...Cotton fiber growth consists of four overlappingdevelopmental stages:fiber initiation,cellelongation,secondary wall deposition andmaturation.To date,great progresses have beenmade on cellulose synthesis and deposition.Theinlation and elongation requires rapid celldivision,differentiation,growth and elongation,which undoubtedly includes expression of展开更多
文摘In this study,composite films consisting of polylactic acid(PLA),ethyl cellulose(EC),and zein were prepared by solution casting method,and their performance and application in chilled fresh meat preservation were investigated.The results showed that the three materials had satisfactory compatibility in the composite film.Addition of EC and zein effectively improved the mechanical properties,thermodynamic properties,surface hydrophilicity,oxygen permeability,and degradation properties of PLA films.When the ratio of PLA to EC was 3:7,the tensile strength and elongation at break reached maximum values of 16.6 MPa and 30.5%,respectively.Moreover,under different conditions,the composite film exhibited better degradability than the PLA film.The composite film with a 3:7 ratio of PLA to EC had the best performance,with a degradation rate of 21.75%after 84 days.Chilled fresh meat wrapped with the composite film showed significantly improved antioxidant,antibacterial,and water-holding properties.
基金Project(2010FJ1011)supported by the Major Project of Science and Technology of Hunan Province,China
文摘The kinetics of reductive leaching of manganese from a low-grade manganese oxide ore were studied using cellulose as reductant in dilute sulfuric acid medium.It was found that when the stirring speed was higher than 200 r/min,the effect of gas film diffusion on manganese extraction efficiency could be neglected,and the kinetic behavior was investigated under the condition of elimination of external diffusion influence on the leaching process.Effects of leaching temperature,mass ratio of cellulose and ore,and the sulfuric acid concentration on manganese extraction efficiency were discussed.The kinetic data were analyzed based on the shrinking core model,which indicated that the leaching process was dominated by both ash layer diffusion and chemical reaction at the initial stage,with the progress of leaching reaction,the rate-controlling step switched to the ash layer diffusion.It was also concluded that the sulfuric acid concentration had the most significant influence on the leaching rate,the reaction orders with respect to the sulfuric acid concentration were 2.102 in the first 60 min,and 3.642 in the later 90 min,while the reaction orders for mass ratio of cellulose and ore were 0.660 and 0.724,respectively.An Arrhenius relationship was used to relate the temperature to the rate of leaching,from which apparent activation energies were calculated to be 46.487 kJ/mol and 62.290 kJ/mol at the two stages,respectively.Finally,the overall leaching rate equations for the manganese dissolution reaction with cellulose in sulphuric acid solution were developed.The morphological changes and mineralogical forms of the ore before and after the chemical treatment were discussed with the support of SEM and XRD analyses.
基金Project(2012zzts101)supported by the Fundamental Research Funds for the Central Universities,China
文摘Carboxylmethyl cellulose(CMC) has become a commercial organic binder in agglomeration of iron ore concentrates. The relative molecular mass and degree of substitution(DS) of CMC have a large impact on its binding performance. The interaction mechanism between CMC and iron ore particles was analyzed through Zeta potential measurements, adsorption measurements and infrared spectra. The results show that the interaction is chemical adsorption-oriented and the CMC's adsorption performance is related to the properties of CMC as well as the type of iron oxides. CMC has a greater affinity to Fe2O3 than Fe3O4, and CMC with higher relative molecular mass shows a higher adsorption isotherm. Pelletization of practical iron ore concentrates added with CMC further illustrates that CMC with higher relative molecular mass or DS exhibits a better binding performance, which is consistent with the results of adsorption tests.
基金Supported by the Key Applied Technology Research and Development Program of Heilongjiang Province(GA15B203)Student Innovation and Pioneer Training Program(SIPT)of Northeast Agricultural University(SIPT,201610224153)
文摘Bacillus subtilis is a representative probiotic widely used in food, medicine, livestock and other industries. In this experiment a strain of Bacillus subtilis was isolated and identified, and its ability to degrade cellulose was also measured. The results showed that Bacillus subtilis had strong capacity to degrade cellulose(62.3% was degraded) and weak capacity to degrade hemicellulose(17.2% was degraded), while it could hardly degrade lignin. The total protein amount in the fermentation medium with cellulose-rich substrate reached by 9.4% after Bacillus subtilis fermentation, compared with that without cellulose-rich substrate. Furthermore, the amounts of Met, Lys and Leu reached by 31.4%, 42.2% and 4.9%, respectively. At 36 h of fermentation, the activity of cellulase reached the highest, and at this time the activity of the enzyme was obtained at 7.19 U · mL-1. The mRNA expression level of the cellulase gene was detected by qPCR, and the experimental group with cellulose substrate was about 2.5 times more than that of the non-cellulose substrate control group. These above results demonstrated that this strain of Bacillus subtilis had a strong ability to degrade cellulose, and synthesize more proteins and restrictive essential amino acids. This study revealed that Bacillus subtilis was a new alternative to ferment cellulose substrates to produce commercial feed or feed additives.
基金Financial support from Universiti Pertahanan Nasional Malaysia,Malaysia for Tabung Amanah PPPI (Defence Research Institute,UPNM)grant-A0014 (UPNM/2023/GPPP/SG/2)funded by Universiti Pertahanan Nasional Malaysia (UPNM),situated in Malaysia+1 种基金This financial backing was made possible through the"Tabung Amanah PPPI"grant,which is affiliated with UPNM’s Defence Research Institutethe grant is identifiable by its unique reference number,"A0014 (UPNM/2023/GPPP/SG/2)"。
文摘This review paper explores the potential of oil palm biomass as a valuable cellulose source for the production of nitrocellulose-based propellants,contributing to the green revolution and sustainable energy solutions.It highlights the availability of the corresponding biomass in Malaysia and in line with global studies,the chemical compositions,as well as a brief description of current technologies for converting biomass of oil palm into value added products specifically cellulose.Steps to achieve maximum utilization of biomass from oil palm industry for cellulose production and prospective source for nitrocellulose-based propellant are also proposed.The methodology section outlines the pretreatment of lignocellulosic fibres,cellulose extraction,and nitrocellulose production processes.Overall,the review underscores the prospective of palm oil biomass as a sustainable cellulose source for propellant manufacturing,while acknowledging the need for further research and advancements in the field.
文摘The design of astonishing combinations of benzoxazine resins with various fillers is nowadays of great interest for high quality products,especially in ballistic armors.The objective of this study is to investigate a new hybrid material prepared as multi-layered composite plate by hand lay-up technique.Different composites were manufactured from Kevlar fabrics reinforced polybenzoxazine,which was filled with silane treated microcrystalline cellulose(MCC Si)at various amounts in the interlayers.The developed materials were tested for their flexural,dynamic mechanical and ballistic performance.The aim was to highlight the effect of adding different amounts of MCC Si on the behavior of the different plates.Compared to the baseline,the dynamic mechanical and bending tests revealed an obvious decrease of the glass transition of 21℃and a notable increase in storage modulus and flexural strength of about 180%and17%,respectively,upon adding 1%MMC Si as filler.Similarly,the ballistic test exhibited an enhancement in kinetic energy absorption for which the composite supplemented with 1%MCC Si had the maximal energy absorption of 166.60 J.These results indicated that the developed panels,with interesting mechanical and ballistic features,are suitable to be employed as raw materials to produce body armor.
文摘Objective This work is designed to fabricate a new low density lipoprotein(LDL)absorbent through a mussel-inspired approach and to evaluate the blood compatibility and adsorption clearance,capacity and selectivity of this technique in vitro.Methods Heparin immobilized cellulose(HeTaCe)hydrogels were fabricated through a mussel-inspired approach.Fourier transform infrared spectroscopy,X-ray photoelectron spectroscopy,thermo gravimetric analysis were used to characterize the chemical compositions of the hydrogels.
基金Supported by Project of Dairy Cows System of Chinese Agricultural Department
文摘The purpose of the experiment is to research the effect of different rapeseed treatments feeding on activity of cellulose enzyme in sheep. Eight male adults of semi-fine wool sheep breeds with the same weight and permanent rurnen cannulas were selected according to 4×4 Latin square design to determine the effect of different rapeseed treatment groups including crushed rapeseed, whole rapeseed, extruded rapeseed （dietary lipid content of =67 g·kg^-1） and control group （dietary lipid content of =30 g·kg^-1） on activity dynamic variation of ruminal celluolytic enzyme in sheep. The results showed that ruminal fluid pH matched up to the condition of fiber degradation and growth of cellulolytic bacterium when fed four diets; but there was significant difference （P〈0.05） for the activity of microcrystalline cellulose, glucanase, salicin enzyme involved in ruminal fiber degradation after fed 2, 4, 6 h.
基金Supported by the Key Applied Technology Research and Development Program of Heilongjiang Province(GA15B203)Student Innovation and Pioneer Training Program(SIPT)of Northeast Agricultural University(SIPT,201610224153)
文摘Bacillus lincheniformis is a representative probiotic, widely used in food, medicine and livestock industries and other industries. In this experiment, a strain of Bacillus lincheniformis was isolated and identified, which was used to ferment celluloserich substrate. The effects were analyzed. The experimental results showed that Bacillus lincheniformis had the capacity to degrade cellulose(32.8% was degraded) and less capacity to degrade hemicellulose(7.9% was degraded), which could not degrade ligin. The total protein contents in the products fermented by Bacillus lincheniformis with cellulose-rich substrate riched by 11.6%, compared with the fermented products with no cellulose-rich substrate, furthermore, the contents of Met, Lys and Leu riched by 14%, 17.5% and 4.1%, respectively. These results showed that Bacillus lincheniformis had the ability to degrade cellulose and it provided experimental data for further utilization.
文摘The mechanistic basis of cellulose biosynthesis in plants has gained ground during last decade or so.The isolation of plant cDNA clones encoding cotton homologs of the bacterial cellulose
基金Project(51174229) supported by the National Natural Science Foundation of China
文摘The effect of solution conditions on the depression of chlorite using CMC (carboxymethyl cellulose) as depressant was studied through flotation tests and adsorption measurements. Flotation and adsorption tests were first studied as a function of initial solution conditions. The results show that electrostatic repulsion between CMC molecules and chlorite surface hinders the approach of the CMC molecules to the chlorite surface and CMC adsorbs to a great extent at high ionic concentration (10-4 mol/L ions as opposed to 0 mol/L ions) or low pH (3 as opposed to 9). The enhanced adsorption density is attributed to the decreased electrostatic repulsion between CMC and mineral surface. The solution condition that yielded the lowest initial adsorbed amount (0 mol/L ions, pH 9) was used as a reference to investigate the response of the adsorbed CMC layer to a switch in solution conditions after adsorption. The two kinds of solution switches (reducing the solution pH or increasing ionic concentration) result in an increased depression effect of CMC on chlorite flotation, as a result of conformational change of CMC pre-adsorbed layer. The change in the flotation recovery of the CMC-coated chlorite following the solution switches is reversible.
文摘Cellulose synthesis could play an important rolein determining certain aspects of cotton fiberquality,and despite it’s abundance in nature,little is known about the biosynthesis of thispolymer.Recent advances in understanding thesynthesis of cellulose come from the analysis ofArabidopsis thaliana cellulose-deficient mutants,and the isolation of a number of genes
基金Projects(81373284,81102344) supported by the National Natural Science Foundation of China
文摘The spherical macroporous cellulose(SMC) was fabricated using medical absorbent cotton as raw material and nano CaCO3 as porogenic agents.And then,the phenylglycine was grafted onto the SMC to obtain the novel spherical macroporous cellulose derivative adsorbent(PSMC).FT-IR and scanning electron microscope(SEM) were employed to characterize the adsorbents and Fe3+ ions served as model solute to evaluate the adsorption property of the adsorbents.The experimental results show that the amount of porogenic agents and the value of pH have obvious influence on adsorption capacity of the adsorbents.The data of adsorption kinetic and isotherm display that the adsorbents possess excellent equilibrium adsorption capacity(348.94 mg/g) and have a bright prospect and considerable potential in the treatment of Fe3+ ions in wastewater.
基金Project(2010DFA41440)supported by China-Japan International CooperationProject(2016TP1007)supported by the Hunan Provincial Science and Technology Plan,ChinaProject(21376269)supported by the National Natural Science Foundation of China
文摘A sustainable process was explored for the preparation of 5-hydroxymethylfurfural(HMF) by catalytic degradation of the waste cotton stalk. Solid super-acid(SO_4^(2-)/ZrO_2) was used as an efficient catalyst for the degradation of cotton stalk. Both decomposition experiments and kinetic study were conducted for the exploration of degradation condition and kinetics mechanism. The optimized experimental conditions are reaction temperature 503 K, reaction time 75 min and dosage of catalyst 30%(mass fraction) based on the decomposition experiments, under which a maximum yield of 27.2% for HMF could be achieved. Kinetic study was then carried out in the presence of SO_4^(2-)/ZrO_2. The theoretical results indicate that the activation energies for reducing sugar and HMF with catalyst are 96.71 k J/mol, 84.21 kJ/mol in the presence of SO_4^(2-)/ZrO_2, and they are 105.96 k J/mol and 119.37 k J/mol in the absence of SO_4^(2-)/ZrO_2.
基金supported in part by the U.S. Department of Agriculture, Agricultural Research Service
文摘Background:The majority of attenuated total reflection Fourier transform infrared(ATR FT-IR)investigations of cotton are focused on the fiber tissue for biological mechanisms and understanding of fiber development and maturity,but rarely on other cotton biomass comp on ents.This work examined in detail the ATR FT-IR spectral features of various cott on tissues/organs at reproductive and maturation stages,an a lyzed and discussed their biological implications.Results:The ATR FT-IR spectra of these tissues/organs were an a lyzed and compared with the focus on the lower wavenumber fingerprinting range.Six outstanding FT-IR bands at 1730,1620,1525,1235,1050 and 895 cm^(-1) represented the major C=O stretching,protein Amide I,Amide II,the O-H/N-H deformation,the total C-O-C stretching and the β-glycosidic linkage in celluloses,respectively,and impacted differently between these organs with the two growth stages.Furthermore,the band intensity at 1620,1525,1235,and 1050 cm^(-1) were exclusively and significantly correlated to the levels of protein(Amide I bond),protein(Amide II bond),cellulose,and hemicellulose,respectively,whereas the band at 1730 cm^(-1) was negatively correlated with ash content.Conclusions:The resulting observations indicated the capability of ATR FT-IR spectroscopy for monitoring changes,transportation,and accumulation of the major chemical components in these tissues over the cotton growth period.In other words,this spectral technology could be an effective tool for physiological,biochemical,and morphological research related to cotton biology and development.
基金financial support and the necessary facilities for this study by the Ecole Militaire polytechnique and the Ludwig-Maximilian University of Munich(LMU)。
文摘In this research,a promising class of insensitive and high-energy dense biopolymers,which contain nitrogen-rich 1H-tetrazol-1-yl acetate and nitrate ester functional groups,was successfully synthesized through tetrazole derivatization and nitration of cellulose and its micro-sized derivative(TNCN and TCMCN).Their molecular structures,physicochemical properties,thermal behaviors,mechanical sensitivities and detonation performances were studied and compared to those of the corresponding nitrocellulose and nitrated micro-sized cellulose(NCN and CMCN).The developed energetic TNCN and TCMCN exhibited insensitive character with excellent features such as density of 1.710 g/cm3and 1.726 g/cm3,nitrogen content of 20.95%and 22.59%,and detonation velocity of 7552 m/s and 7786 m/s,respectively,and thereby demonstrate their potential applications as new generation of energetic biopolymers to substitute the common NCN.Furthermore,thermal results showed that the designed nitrated and chemical modified cellulosic biopolymers displayed good thermal stability with multistep decomposition mechanism.These results enrich future prospects for the design of promising insensitive and high-energy dense cellulose-rich materials and commence a new chapter in this field.
文摘Cotton fiber growth consists of four overlappingdevelopmental stages:fiber initiation,cellelongation,secondary wall deposition andmaturation.To date,great progresses have beenmade on cellulose synthesis and deposition.Theinlation and elongation requires rapid celldivision,differentiation,growth and elongation,which undoubtedly includes expression of
