The styrene-butadiene-styrene(SBS) modified bitumens with different contents of SBS modifiers are stored in different conditions to study the storage stability of SBS modified bitumen.Mixed-level orthogonal array de...The styrene-butadiene-styrene(SBS) modified bitumens with different contents of SBS modifiers are stored in different conditions to study the storage stability of SBS modified bitumen.Mixed-level orthogonal array design(OAD) is used and factors such as SBS modifier content,storage time,storage temperature and container size are chosen in a mixed-level OAD with an OA16(31×44) matrix.Parameters like the separation softening point difference(the separation difference of the ring and ball softening point of the top and bottom samples) and the average softening point(the arithmetic mean of the softening points of the top and bottom samples) are proposed to evaluate the separation and the ageing of modified bitumen during storage in this experiment,respectively.The results reveal that the separation and the ageing during storage exhibit a complicated variation for storage temperature and time.The separation softening point difference decreases with the storage temperature rising from 20 to 120 ℃ and increases with the temperature exceeding 120 ℃,and the average softening point drops with the storage time being prolonged.Different storage conditions have various effects on the storage stability of SBS modified bitumen.展开更多
In this paper,we investigated the effects of temperature,oxygen,antioxidants,and corn germ oil on the stability of astaxanthin from Haematococcus pluvialis under different storage conditions,and changes in the composi...In this paper,we investigated the effects of temperature,oxygen,antioxidants,and corn germ oil on the stability of astaxanthin from Haematococcus pluvialis under different storage conditions,and changes in the composition of astaxanthin esters during storage using high performance liquid chromatography and spectrophotometry.Oxygen and high temperatures(22–25°C) significantly reduced the stability of astaxanthin esters.Corn germ oil and antioxidants(ascorbic acid and vitamin E)failed to protect astaxanthin from oxidation,and actually significantly increased the instability of astaxanthin.A change in the relative composition of astaxanthin esters was observed after 96 weeks of long-term storage.During storage,the relative amounts of free astaxanthin and astaxanthin monoesters declined,while the relative amount of astaxanthin diesters increased.Thus,the ratio of astaxanthin diester to monoester increased,and this ratio could be used to indicate if astaxanthin esters have been properly preserved.If the ratio is greater than 0.2,it suggests that the decrease in astaxanthin content could be higher than 20%.Our results show that storing algal powder from H.pluvialis or other natural astaxanthin products under vacuum and in the dark below 4°C is the most economical and applicable storage method for the large-scale production of astaxanthin from H.pluvialis.This storage method can produce an astaxanthin preservation rate of at least 80%after 96 weeks of storage.展开更多
The effect of absence of lipoxygenase isoenzyme (LOX) on storage stability was investigated. Rice mutant 1297 without lipoxygenase isoenzyme-1 (LOX-1) or lipoxygenase isoenzyme-2 (LOX-2) generated by ion beam ir...The effect of absence of lipoxygenase isoenzyme (LOX) on storage stability was investigated. Rice mutant 1297 without lipoxygenase isoenzyme-1 (LOX-1) or lipoxygenase isoenzyme-2 (LOX-2) generated by ion beam irradiation from Wanjian2090 and reversion mutant RM1297 with LOX-1 and LOX-2 were subjected to an accelerated-aging experiment. Shanyou63 (with LOX-1 and LOX-2 ) served as control. Results showed that the germination and dehydrogenase activity decreased while the electrical conductivity and free fatty acid content increased in all varieties with accelerated aging. In 1297 that lacked LOX-1 and 2, there were slight changes in germination, dehydrogenase activity, membrane permeability and free fatty acid content during the thirty-day accelerated-aging experiment. But in varieties with LOX-1 and LOX-2, significant changes were observed, suggesting that LOX-1, 2 might be a definite factor which influenced seed lifespan. This study also indicates that ion beam irradiation may be used as mutagen to generate mutant and reversion mutants for biological study and could become a new direction in ion beam application.展开更多
Microwave,as a new heat treatment technology,has the characteristics of uniform and fast heating speed.It is an energy-saving technology known for improving oilseed product quality.Its efficiency mainly depends on the...Microwave,as a new heat treatment technology,has the characteristics of uniform and fast heating speed.It is an energy-saving technology known for improving oilseed product quality.Its efficiency mainly depends on the roasting power and time.However,the production of high-quality peanut butter using short-time roasting con-ditions are limited.Herein,we determined an appropriate microwave roasting power and time for peanuts and evaluated its impacts on the quality of peanut butter.Different roasting powers(400 W,800 W and 1200 W)and times(4,4.5,5,and 5.5 min)were preliminarily tested.Among them,800 W at 5 min was the most suitable.The roasting efficiency was further evaluated using color,sensory,bioactive compounds,storage stability,and safety risk factors of peanut butter produced from four peanut cultivars(Silihong,Baisha-1016,Yuanza-9102,and Yuhua-9414).The pre-treated butter obtained from three cultivars(Silihong,Yuanza-9102,and Yuhua-9414)with moisture content between 5%and 7.2%had a similar sensory score(6-7)as the commercial on a 9-point hedonic scale compare to the other.The color of the pre-treated peanut butter varies statistically with the commercial but remained in the recommended range of Hunter L*values of 51-52,respectively,for high initial moisture peanut cultivars.The total polyphenol(35.20-31.59±0.59μmol GAE/g)and tocopherol(19.05±0.35 mg/100 g)content in the butter obtained from three cultivars(Yuahua-9102,Yuhua,and Baisha-1016)and Silihong respectively,were significantly(P<0.05)higher than those in the commercial butter.The induction times of all pre-treated butter(19.80±0.99-7.84±0.07 h)were significantly(P<0.05)longer during storage at accelerated temperature than commercial samples.In addition,no benzo[a]pyrene was found in the pre-treated samples.Collectively,the microwave pretreated peanut butter was superior to the commercial one.These findings provided data support and a reference basis to promote microwave use for peanut butter production.展开更多
This study examined the effect of peanut quality on the storage stability of peanut butter. The quality of 17 varieties of peanuts was analyzed, and each was used to prepare peanut butter. For different storage temper...This study examined the effect of peanut quality on the storage stability of peanut butter. The quality of 17 varieties of peanuts was analyzed, and each was used to prepare peanut butter. For different storage temperatures and durations, stability of the peanut butter was measured according to three indicators: peroxide value, acid value, and centrifugal rate. The correlation between peanut components and peanut butter storage stability was also investigated. The results indicated significant differences in fatty acid composition between different varieties of peanut. Peanut butter prepared with high oleic peanuts(Kainong 17-15) had a significantly longer shelf life than that of other varieties. The significant correlation between the stability of peanut butter and peanut quality suggests that oleic acid and linoleic acid were the main influencing factors on stability. This study finds that the high oleic peanuts(HOP) is the most suitable variety for making peanut butter, which can allow farmers and processors to choose the specific variety for better product and shelf life.展开更多
The high-temperature β-phase NaMnO2 is a promising material for Na-ion batteries(NIBs) due to its high capacity and abundant resources. However, the synthesis of phase-pure -NaMnO2 is burdensome and costineffective...The high-temperature β-phase NaMnO2 is a promising material for Na-ion batteries(NIBs) due to its high capacity and abundant resources. However, the synthesis of phase-pure -NaMnO2 is burdensome and costineffective because it needs to be sintered under oxygen atmosphere at high temperature and followed by a quenching procedure. Here we first report that the pure β phase can be stabilized by Cu-doping and easily synthesized by replacing a proportion of Mn with Cu via a simplified process including sintering in air and cooling to room temperature naturally. Based on the first-principle calculations, the band gap decreases from 0.7 eV to 0.3 eV, which indicates that the electronic conductivity can be improved by Cu-doping. The designed -NaCu(0.1)Mn(0.9)O2 is applied as cathode in NIBs, exhibiting an energy density of 419 Wh/kg and better performance in terms of rate capability and cycling stability than those in the undoped case.展开更多
The effects of temperature,pH and long-term storage on the secondary structure and conformation changes of bovine haemoglobin(bHb) were studied using circular dichroism(CD) and ultraviolet-visible(UV-vis) spectr...The effects of temperature,pH and long-term storage on the secondary structure and conformation changes of bovine haemoglobin(bHb) were studied using circular dichroism(CD) and ultraviolet-visible(UV-vis) spectroscopies.Neural network software was used to deconvolute the CD data to obtain the fractional content of the five secondary structures.The storage stability of bHb solutions in pH 6,7 and8 buffers was significantly higher at 4 ℃ than at 23 ℃ for the first 3 days.A complete denaturation of bHb was observed after 40 days irrespective of storage temperature or pH.The bHb solutions were also exposed to heating and cooling cycles between 25 and 65 ℃ and structural changes were followed by UVvis and CD spectroscopies.These experiments demonstrated that α-helix content of bHb decreased steadily with the increasing temperature above 35 ℃ at all pH values.The loss in a-helicity and gain in random coil conformations was pH-dependent and the greatest under alkaline conditions.Furthermore,there was minimal recovery of the secondary structure content upon cooling to 25 ℃.The use of bHb as a model drug is very common and this study elucidates the significance of storage and processing conditions on its stability.展开更多
Biodiesel is a biomass-based renewable and clean fuel. It can be used directly in existing diesel engines without any modification. In spite of having so many advantages, it has an issue regarding long-term storage st...Biodiesel is a biomass-based renewable and clean fuel. It can be used directly in existing diesel engines without any modification. In spite of having so many advantages, it has an issue regarding long-term storage stability. Biodiesel oxidizes when it comes in proximity of light, temperature, humidity, metals etc. The oxidation causes precipitation and sedimentation in the fuel. Such biodiesel is unfit to use in engines. Hence, this study aims to assess the storage stability of pomelo seed oil (Citrus maxima) biodiesel over a period of five months upon storage both in open and closed condition. Storage stability of biodiesel is determined in terms of acid value, peroxide value and viscosity at regular interval of time. It is observed that there is a strong relationship between oxidation and outside factors such as light, temperature fluctuations and humidity level. Upon exposure to these factors, oxidation in biodiesel accelerated greatly.展开更多
Alpha-lipoic acid-loaded lipid nanoparticles(ALA-LNs) were prepared by high pressure homogenization method.The influences of storage conditions such as time and temperature on the physical and chemical storage stabili...Alpha-lipoic acid-loaded lipid nanoparticles(ALA-LNs) were prepared by high pressure homogenization method.The influences of storage conditions such as time and temperature on the physical and chemical storage stability of ALA-LNs were studied in details.The stability was evaluated by particle size and polydispersity index,morphology of ALA-LNs,and capacity of ALA loading.The dilution and pH stability of ALA-LNs suspensions were also studied.After three months storage,the mean size of ALA-LNs at 4 and 40 ℃ was increased by 2.68% and 3.62% compared with the original size,respectively.ALA-LNs stored at 40 ℃ had ellipsoid shape and the mean size was about 152 nm(SD=23.6).The loading capacity of ALA at 40 ℃ was much higher than those stored at other two temperatures.The good dilution and pH stability were also demonstrated.The sample had good fluidity even at 4 ℃.展开更多
According to the conductivity test results,it is found that oil conductivity increases with an increasing additive content,and the turbidity of engine oil is also augmented with an increasing additive content.After te...According to the conductivity test results,it is found that oil conductivity increases with an increasing additive content,and the turbidity of engine oil is also augmented with an increasing additive content.After testing the turbidity and stability of oils containing the typical conventional calcium sulfonate,the overbased calcium sulfonate and the mixture of the above two calcium sulfonates,the results show that at the same amount of additives used,the oil with a higher turbidity demonstrated a worse stability.A nonionic dispersant that was added into lube oils at a definite concentration could improve the detergent compatibility.For this reason,the sediment volume in three kinds of oils all decreased obviously,resulting in successful improvement of storage stability of marine engine oils.展开更多
The Qinghai-Tibet Plateau(QTP)distributes the largest extent of high-altitude mountain permafrost in the world(Zou et al.,2017),which has different characteristics from high-latitude permafrost(Yang et al.,2010)and st...The Qinghai-Tibet Plateau(QTP)distributes the largest extent of high-altitude mountain permafrost in the world(Zou et al.,2017),which has different characteristics from high-latitude permafrost(Yang et al.,2010)and stores massive soil carbon.展开更多
The storage stability and degradation trends of imidacloprid residues in different matrix of Lycium barbarum were investigated by directly adding 0.1 mg/kg imidacloprid, frozen storage and phase detection. The results...The storage stability and degradation trends of imidacloprid residues in different matrix of Lycium barbarum were investigated by directly adding 0.1 mg/kg imidacloprid, frozen storage and phase detection. The results showed that under frozen condition, the storage stability of imidacloprid residues remained good for half a year in dry fruit, and a year in fresh fruit of L. barbarum . There was no significant change of imidacloprid residues between different processing of dry fruit and fresh fruit, and sample processing methods (crushing or homogenizing) had no significant effect on the degradation trends of imidacloprid. Therefore, the samples could be processed into crushed samples or homogenized samples for storage as soon as possible according to the needs, and the dry fruit should be detected within half a year, while the fresh fruit should be detected within a year.展开更多
Waterborne coatings often delaminate and settle during long-term storage,requiring the addition of thickeners.The effects of nanofibrillated cellulose(NFC)and the commonly used thickener,hydroxyethyl cellulose(HEC),on...Waterborne coatings often delaminate and settle during long-term storage,requiring the addition of thickeners.The effects of nanofibrillated cellulose(NFC)and the commonly used thickener,hydroxyethyl cellulose(HEC),on the storage stability of waterborne coatings were compared in this study.The morphology of NFC was characterized using infrared spectroscopy(FT-IR)and scanning electron microscopy(SEM).The rotational viscosity and rheological properties of the waterborne coatings with NFC and HEC were tested.Stationary settling experiments were also conducted at different temperatures to compare the difference of NFC and HEC on improving the storage stability of the waterborne coatings.The results showed that the waterborne coating with NFC exhibited pseudoplastic fluid characteristics;a small addition of NFC can achieve the same improvement effect on the storage stability of waterborne coatings as HEC.Further,the improvement effect of NFC was not affected by temperature.The waterborne coating with NFC still exhibited good storage stability at high temperatures,which was significantly superior to that of HEC.Therefore,NFC is a feasible agent for improving the prolonged storage stability and warming-induced delamination of waterborne coatings.展开更多
To achieve the controllable release of energy of nitrocellulose-based propellants,this paper combines the cellulose-based nanocomposites aqueous coating(Surelease®-NC)with fluidized bed coating equipment to succe...To achieve the controllable release of energy of nitrocellulose-based propellants,this paper combines the cellulose-based nanocomposites aqueous coating(Surelease®-NC)with fluidized bed coating equipment to successfully prepare the coated spherical propellant for the first time.The effects of fluidized bed coating temperature,air velocity,flow speed and atomization pressure on the adhesion rate,coating integrity and coating uniformity of the coated spherical propellant were investigated,and the preparation of coated spherical propellant with homogeneous size and structural integrity was achieved for the first time.The microscopic morphology,chemical structure,water vapor adsorption behavior,combustion performance,and ageing resistance property of the coated spherical propellant were systematically investigated by,Fourier transforms infrared spectroscopy(FTIR),Micro confocal raman spectrometer,field scanning electron microscopy(SEM),dynamic vapor adsorption techniques,and closed bomb test,confirming the surface core-shell structure and the tightly bonded interfacial structure of coated spherical propellant.Meanwhile,the coated spherical propellant has good hygroscopic,excellent progressive burning and long storage stability.展开更多
For the production of reactive polyurethane cross-linkinger and curing agents, 2, 4-diisocyanate toluene (TDI) terpolymer, which possesses the rigid structures of hexatomic ring and three reactive functional groups,...For the production of reactive polyurethane cross-linkinger and curing agents, 2, 4-diisocyanate toluene (TDI) terpolymer, which possesses the rigid structures of hexatomic ring and three reactive functional groups, was synthesized and characterized by the Fourier transform infrared (FFIR), the gel permeation chromatography (GPC) and the chemical analysis methods. The reaction conditions were studied and optimized. A tracking research on the polymerization process of TDI was taken by using the GPC. The formation processes of the terpolymer, oligomers and higher-polymers were also dealt with. Results show that the TDI terpolymer can be prepared in the presence of Cat-3 catalyst and at the reaction temperature of (60 ±2)℃. The reaction time is short, its outcomes have narrow molecular weights distribution, namely molecular weights from 530 to 550, Mw/Mn =1.10, and the mass fraction of NCO is (25. 0 ± 0. 5)%. With the reaction time prolonging, however, TDI can be further higher-polymedzed to form higher-polymers. Benzoyl chloride (0. 4%, mass fraction), as the stabilizing agent, can effectively inhibit the occurrence of higher-polymerization. The obtained TDI terpolymer can be stable for more than half a year.展开更多
We determined the effects of different pre-freezing temperatures (−20℃ and −80℃) on the freeze-drying survival rate and stability during room temperature storage of Lactiplantibacillus plantarum LIP-1. The underlyin...We determined the effects of different pre-freezing temperatures (−20℃ and −80℃) on the freeze-drying survival rate and stability during room temperature storage of Lactiplantibacillus plantarum LIP-1. The underlying mechanisms of survival and stability were also assessed. The freeze-drying survival rate and stability during room temperature storage of Lactiplantibacillus plantarum LIP-1 was significantly higher in the −80℃ than −20℃ group (p <0.05). Regarding the underlying mechanism, compared with the −20℃ group, the −80℃ group had a lower level of intracellular reactive oxygen species, lower degree of oxidation of fatty acids in the cell membrane, high integrity and fluidity of the cell membrane during freeze-drying and room temperature storage, and a significantly higher freeze-drying survival rate and storage stability (p<0.05). This study provides reference data that could help improve the freeze-drying survival rate and stability of probiotics during room temperature storage.展开更多
In this paper,a kind of wall fabric’s surface treatment agent modified with nonionic surfactant was reported.This surface treatment agent was prepared by using nano tourmaline powder dispersion in water with surfacta...In this paper,a kind of wall fabric’s surface treatment agent modified with nonionic surfactant was reported.This surface treatment agent was prepared by using nano tourmaline powder dispersion in water with surfactant as dispersants by sand milling.Under the influence of different dispersants,the negative ions releasing amount of functional wall fabrics,the milling process and the storage stability of nano tourmaline powder dispersion were discussed.The results showed that nano tourmaline powder dispersion achieved the smallest average diameter of 44 nm and had best storage stability that the average diameter maintained below 200 nm in 17 days when the addition amount of dispersant was 20 percent of the tourmaline powders’weight.What is more,the quantity of negative ion releasing achieved 6500 ion/cm3 when addition amount of dispersant was 30 percent.This technique could be used to strengthen productivity of nano tourmaline powder dispersion.展开更多
In this paper,organic montmorillonite(OMMT)was added into crumb rubber modified asphalt(CRMA)to improve its high temperature performance,anti-aging performance and storage stability.The effects of different OMMT conte...In this paper,organic montmorillonite(OMMT)was added into crumb rubber modified asphalt(CRMA)to improve its high temperature performance,anti-aging performance and storage stability.The effects of different OMMT content on properties of CRMA were studied.The rutting factor obtained by dynamic shear rheological(DSR)test was adopted to evaluate the high-temperature performance.The creep stiffness and m value determined by the bending beam rheometer(BBR)test were employed to evaluate the low-temperature performance.The softening point,ductility,rutting factor before and after rolling thin film ovens test(RTFOT)and pressure aging vessel test(PAV)were compared to characterize the aging properties.Moreover,the segregation test after being reserved for 48 h and 7 d was conducted,and the softening point and rutting factor of upper and lower layers of segregation pipe were adopted to evaluate the storage stability.The results indicated that the high-temperature performance and anti-aging performance were developed with the increasing content of OMMT,while the low-temperature performance deteriorated.The storage stability was improved with the increasing content of OMMT before the content exceeded 4%,after which the storage stability declined.Taking account of all factors,it is suggested that the optimum content of OMMT is 3%−4%.展开更多
Biodiesel(fatty acid alkyl esters),an alternate to fossil fuel,has the tendency of autoxidation and hence requires antioxidants for long term storage.The influence of synthetic and natural antioxidants on the oxidativ...Biodiesel(fatty acid alkyl esters),an alternate to fossil fuel,has the tendency of autoxidation and hence requires antioxidants for long term storage.The influence of synthetic and natural antioxidants on the oxidative stability was analysed for fresh FAMEs(fatty acid methyl esters)obtained from hevea brasiliensis at 140 C.Higher activity was observed for synthetic antioxidants following the order of GA】BHT】DTBP】Q】GT-M】PH-M】GT-C,whereas the oxidative stability of stored FAMEs samples measured at 110 C reveals a nearly inverse trend.Storage stability was tested for the FAMEs obtained from hevea brasiliensis stored at 30 C,after addition of synthetic and natural antioxidants—butylated hydroxytoluene(BHT),2,6-di-tert-butylphenol(DTBP),quercetin(Q),gallic acid(GA),methanol extracts from green tea(GTM),pomegranate hull(PH-M),and chloroform extract of green tea(GT-C).Antioxidant activities above 1500 ppm was in the order of DTBP】BHT】GA】GT-C】GT-M】Q】PH-M.Synthetic antioxidants have been found more efficient to improve the storage stability of FAMEs obtained from hevea brasiliensis.DTBP in particular has the highest protection factor.展开更多
Evidences show that the storage period greatly affects the quality of yogurt.In this study,three types of yogurt:control yogurt(CY),non-hydrolyzed potato powder yogurt(PPY)and enzymatically hydrolyzed potato powder yo...Evidences show that the storage period greatly affects the quality of yogurt.In this study,three types of yogurt:control yogurt(CY),non-hydrolyzed potato powder yogurt(PPY)and enzymatically hydrolyzed potato powder yogurt(EHPPY)were prepared at 42℃ for 5 h and stored for 28 days at 4℃.The yogurts were evaluated for quality characteristics at different storage periods.Negligible differences in pH values,titratable acidities and viable counts were detected in all three types of yogurt during storage.However,compared to other yogurts,EHPPY exhibited desirable water holding capacity,throughout the storage period.Apart from this,sensory properties and antioxidant activities(2-diphenyl-1-picryl-hydrazyl(DPPH)free radical scavenging activity and ferric reducing antioxidant power(FRAP))of EHPPY were also significantly improved during the storage period.Furthermore,the storage(G’)and loss(G”)modulus of PPY,EHPPY were lower than CY at 4℃ while a hysteresis loop was shown by all yogurts at the temperature range of 4-50℃ indicating higher G’(elasticity)than G”(viscosity).Based on our findings,EHPP could be an important functional ingredient in improving the quality and storage stability of yogurt for its production at an industrial level.展开更多
基金The National Natural Science Foundation of China (No.51178348)
文摘The styrene-butadiene-styrene(SBS) modified bitumens with different contents of SBS modifiers are stored in different conditions to study the storage stability of SBS modified bitumen.Mixed-level orthogonal array design(OAD) is used and factors such as SBS modifier content,storage time,storage temperature and container size are chosen in a mixed-level OAD with an OA16(31×44) matrix.Parameters like the separation softening point difference(the separation difference of the ring and ball softening point of the top and bottom samples) and the average softening point(the arithmetic mean of the softening points of the top and bottom samples) are proposed to evaluate the separation and the ageing of modified bitumen during storage in this experiment,respectively.The results reveal that the separation and the ageing during storage exhibit a complicated variation for storage temperature and time.The separation softening point difference decreases with the storage temperature rising from 20 to 120 ℃ and increases with the temperature exceeding 120 ℃,and the average softening point drops with the storage time being prolonged.Different storage conditions have various effects on the storage stability of SBS modified bitumen.
基金Supported by the Yunnan Provincial Sciences and Technology Department,China(No.2007AD009)the National Natural Science Foundation of China(No.31272680)the Ministry of Science and Technology of China(No.2013AA065805)
文摘In this paper,we investigated the effects of temperature,oxygen,antioxidants,and corn germ oil on the stability of astaxanthin from Haematococcus pluvialis under different storage conditions,and changes in the composition of astaxanthin esters during storage using high performance liquid chromatography and spectrophotometry.Oxygen and high temperatures(22–25°C) significantly reduced the stability of astaxanthin esters.Corn germ oil and antioxidants(ascorbic acid and vitamin E)failed to protect astaxanthin from oxidation,and actually significantly increased the instability of astaxanthin.A change in the relative composition of astaxanthin esters was observed after 96 weeks of long-term storage.During storage,the relative amounts of free astaxanthin and astaxanthin monoesters declined,while the relative amount of astaxanthin diesters increased.Thus,the ratio of astaxanthin diester to monoester increased,and this ratio could be used to indicate if astaxanthin esters have been properly preserved.If the ratio is greater than 0.2,it suggests that the decrease in astaxanthin content could be higher than 20%.Our results show that storing algal powder from H.pluvialis or other natural astaxanthin products under vacuum and in the dark below 4°C is the most economical and applicable storage method for the large-scale production of astaxanthin from H.pluvialis.This storage method can produce an astaxanthin preservation rate of at least 80%after 96 weeks of storage.
基金supported by the Knowledge Innovative Program of the Chinese Academy of Sciences(No.KSCX-SW-32)
文摘The effect of absence of lipoxygenase isoenzyme (LOX) on storage stability was investigated. Rice mutant 1297 without lipoxygenase isoenzyme-1 (LOX-1) or lipoxygenase isoenzyme-2 (LOX-2) generated by ion beam irradiation from Wanjian2090 and reversion mutant RM1297 with LOX-1 and LOX-2 were subjected to an accelerated-aging experiment. Shanyou63 (with LOX-1 and LOX-2 ) served as control. Results showed that the germination and dehydrogenase activity decreased while the electrical conductivity and free fatty acid content increased in all varieties with accelerated aging. In 1297 that lacked LOX-1 and 2, there were slight changes in germination, dehydrogenase activity, membrane permeability and free fatty acid content during the thirty-day accelerated-aging experiment. But in varieties with LOX-1 and LOX-2, significant changes were observed, suggesting that LOX-1, 2 might be a definite factor which influenced seed lifespan. This study also indicates that ion beam irradiation may be used as mutagen to generate mutant and reversion mutants for biological study and could become a new direction in ion beam application.
基金Key Research Projects of Hubei Province(2020BBA045)the Agricultural Science and Technology Innovation Project of the Chinese Academy of Agricultural Sciences(CAAS-ASTIP-2016-OCRI)。
文摘Microwave,as a new heat treatment technology,has the characteristics of uniform and fast heating speed.It is an energy-saving technology known for improving oilseed product quality.Its efficiency mainly depends on the roasting power and time.However,the production of high-quality peanut butter using short-time roasting con-ditions are limited.Herein,we determined an appropriate microwave roasting power and time for peanuts and evaluated its impacts on the quality of peanut butter.Different roasting powers(400 W,800 W and 1200 W)and times(4,4.5,5,and 5.5 min)were preliminarily tested.Among them,800 W at 5 min was the most suitable.The roasting efficiency was further evaluated using color,sensory,bioactive compounds,storage stability,and safety risk factors of peanut butter produced from four peanut cultivars(Silihong,Baisha-1016,Yuanza-9102,and Yuhua-9414).The pre-treated butter obtained from three cultivars(Silihong,Yuanza-9102,and Yuhua-9414)with moisture content between 5%and 7.2%had a similar sensory score(6-7)as the commercial on a 9-point hedonic scale compare to the other.The color of the pre-treated peanut butter varies statistically with the commercial but remained in the recommended range of Hunter L*values of 51-52,respectively,for high initial moisture peanut cultivars.The total polyphenol(35.20-31.59±0.59μmol GAE/g)and tocopherol(19.05±0.35 mg/100 g)content in the butter obtained from three cultivars(Yuahua-9102,Yuhua,and Baisha-1016)and Silihong respectively,were significantly(P<0.05)higher than those in the commercial butter.The induction times of all pre-treated butter(19.80±0.99-7.84±0.07 h)were significantly(P<0.05)longer during storage at accelerated temperature than commercial samples.In addition,no benzo[a]pyrene was found in the pre-treated samples.Collectively,the microwave pretreated peanut butter was superior to the commercial one.These findings provided data support and a reference basis to promote microwave use for peanut butter production.
基金financial support from the National Key Research and Development Program of China (2016YFD0400200)the Agricultural Science and Technology Innovation Program of the Chinese Academy of Agricultural Sciences (CAAS-ASTIP-201X-IAPPST)the Central Public-interest Scientific Institution Basal Research Fund, China (Y2017CG10)
文摘This study examined the effect of peanut quality on the storage stability of peanut butter. The quality of 17 varieties of peanuts was analyzed, and each was used to prepare peanut butter. For different storage temperatures and durations, stability of the peanut butter was measured according to three indicators: peroxide value, acid value, and centrifugal rate. The correlation between peanut components and peanut butter storage stability was also investigated. The results indicated significant differences in fatty acid composition between different varieties of peanut. Peanut butter prepared with high oleic peanuts(Kainong 17-15) had a significantly longer shelf life than that of other varieties. The significant correlation between the stability of peanut butter and peanut quality suggests that oleic acid and linoleic acid were the main influencing factors on stability. This study finds that the high oleic peanuts(HOP) is the most suitable variety for making peanut butter, which can allow farmers and processors to choose the specific variety for better product and shelf life.
基金Supported by the National Key Technologies R&D Program of China under Grant No 2016YFB0901500the National Nature Science Foundation of China under Grant Nos 51725206 and 51421002
文摘The high-temperature β-phase NaMnO2 is a promising material for Na-ion batteries(NIBs) due to its high capacity and abundant resources. However, the synthesis of phase-pure -NaMnO2 is burdensome and costineffective because it needs to be sintered under oxygen atmosphere at high temperature and followed by a quenching procedure. Here we first report that the pure β phase can be stabilized by Cu-doping and easily synthesized by replacing a proportion of Mn with Cu via a simplified process including sintering in air and cooling to room temperature naturally. Based on the first-principle calculations, the band gap decreases from 0.7 eV to 0.3 eV, which indicates that the electronic conductivity can be improved by Cu-doping. The designed -NaCu(0.1)Mn(0.9)O2 is applied as cathode in NIBs, exhibiting an energy density of 419 Wh/kg and better performance in terms of rate capability and cycling stability than those in the undoped case.
基金the University of Greenwich for financial support
文摘The effects of temperature,pH and long-term storage on the secondary structure and conformation changes of bovine haemoglobin(bHb) were studied using circular dichroism(CD) and ultraviolet-visible(UV-vis) spectroscopies.Neural network software was used to deconvolute the CD data to obtain the fractional content of the five secondary structures.The storage stability of bHb solutions in pH 6,7 and8 buffers was significantly higher at 4 ℃ than at 23 ℃ for the first 3 days.A complete denaturation of bHb was observed after 40 days irrespective of storage temperature or pH.The bHb solutions were also exposed to heating and cooling cycles between 25 and 65 ℃ and structural changes were followed by UVvis and CD spectroscopies.These experiments demonstrated that α-helix content of bHb decreased steadily with the increasing temperature above 35 ℃ at all pH values.The loss in a-helicity and gain in random coil conformations was pH-dependent and the greatest under alkaline conditions.Furthermore,there was minimal recovery of the secondary structure content upon cooling to 25 ℃.The use of bHb as a model drug is very common and this study elucidates the significance of storage and processing conditions on its stability.
文摘Biodiesel is a biomass-based renewable and clean fuel. It can be used directly in existing diesel engines without any modification. In spite of having so many advantages, it has an issue regarding long-term storage stability. Biodiesel oxidizes when it comes in proximity of light, temperature, humidity, metals etc. The oxidation causes precipitation and sedimentation in the fuel. Such biodiesel is unfit to use in engines. Hence, this study aims to assess the storage stability of pomelo seed oil (Citrus maxima) biodiesel over a period of five months upon storage both in open and closed condition. Storage stability of biodiesel is determined in terms of acid value, peroxide value and viscosity at regular interval of time. It is observed that there is a strong relationship between oxidation and outside factors such as light, temperature fluctuations and humidity level. Upon exposure to these factors, oxidation in biodiesel accelerated greatly.
基金Supported by International Scientific Cooperation Project of China (No.2008DFB50060)Suzhou Innovation Funds of High-Tech Enterprise (No.SG0958)
文摘Alpha-lipoic acid-loaded lipid nanoparticles(ALA-LNs) were prepared by high pressure homogenization method.The influences of storage conditions such as time and temperature on the physical and chemical storage stability of ALA-LNs were studied in details.The stability was evaluated by particle size and polydispersity index,morphology of ALA-LNs,and capacity of ALA loading.The dilution and pH stability of ALA-LNs suspensions were also studied.After three months storage,the mean size of ALA-LNs at 4 and 40 ℃ was increased by 2.68% and 3.62% compared with the original size,respectively.ALA-LNs stored at 40 ℃ had ellipsoid shape and the mean size was about 152 nm(SD=23.6).The loading capacity of ALA at 40 ℃ was much higher than those stored at other two temperatures.The good dilution and pH stability were also demonstrated.The sample had good fluidity even at 4 ℃.
文摘According to the conductivity test results,it is found that oil conductivity increases with an increasing additive content,and the turbidity of engine oil is also augmented with an increasing additive content.After testing the turbidity and stability of oils containing the typical conventional calcium sulfonate,the overbased calcium sulfonate and the mixture of the above two calcium sulfonates,the results show that at the same amount of additives used,the oil with a higher turbidity demonstrated a worse stability.A nonionic dispersant that was added into lube oils at a definite concentration could improve the detergent compatibility.For this reason,the sediment volume in three kinds of oils all decreased obviously,resulting in successful improvement of storage stability of marine engine oils.
基金financially supported by the National Natural Science Foundation of China(41871064)the Second Tibetan Plateau Scientific Expedition and Research Program(2019QZKK0304)。
文摘The Qinghai-Tibet Plateau(QTP)distributes the largest extent of high-altitude mountain permafrost in the world(Zou et al.,2017),which has different characteristics from high-latitude permafrost(Yang et al.,2010)and stores massive soil carbon.
基金Supported by the Planning Project for Quality Safety Risk Assessment of National Agricultural Products of China(GJFP201701002)
文摘The storage stability and degradation trends of imidacloprid residues in different matrix of Lycium barbarum were investigated by directly adding 0.1 mg/kg imidacloprid, frozen storage and phase detection. The results showed that under frozen condition, the storage stability of imidacloprid residues remained good for half a year in dry fruit, and a year in fresh fruit of L. barbarum . There was no significant change of imidacloprid residues between different processing of dry fruit and fresh fruit, and sample processing methods (crushing or homogenizing) had no significant effect on the degradation trends of imidacloprid. Therefore, the samples could be processed into crushed samples or homogenized samples for storage as soon as possible according to the needs, and the dry fruit should be detected within half a year, while the fresh fruit should be detected within a year.
文摘Waterborne coatings often delaminate and settle during long-term storage,requiring the addition of thickeners.The effects of nanofibrillated cellulose(NFC)and the commonly used thickener,hydroxyethyl cellulose(HEC),on the storage stability of waterborne coatings were compared in this study.The morphology of NFC was characterized using infrared spectroscopy(FT-IR)and scanning electron microscopy(SEM).The rotational viscosity and rheological properties of the waterborne coatings with NFC and HEC were tested.Stationary settling experiments were also conducted at different temperatures to compare the difference of NFC and HEC on improving the storage stability of the waterborne coatings.The results showed that the waterborne coating with NFC exhibited pseudoplastic fluid characteristics;a small addition of NFC can achieve the same improvement effect on the storage stability of waterborne coatings as HEC.Further,the improvement effect of NFC was not affected by temperature.The waterborne coating with NFC still exhibited good storage stability at high temperatures,which was significantly superior to that of HEC.Therefore,NFC is a feasible agent for improving the prolonged storage stability and warming-induced delamination of waterborne coatings.
基金supported by the National Natural Science Foundation of China (Grant No.22005143)Young Elite Scientists Sponsorship Program by CAST (Grant No.2022QNRC001)。
文摘To achieve the controllable release of energy of nitrocellulose-based propellants,this paper combines the cellulose-based nanocomposites aqueous coating(Surelease®-NC)with fluidized bed coating equipment to successfully prepare the coated spherical propellant for the first time.The effects of fluidized bed coating temperature,air velocity,flow speed and atomization pressure on the adhesion rate,coating integrity and coating uniformity of the coated spherical propellant were investigated,and the preparation of coated spherical propellant with homogeneous size and structural integrity was achieved for the first time.The microscopic morphology,chemical structure,water vapor adsorption behavior,combustion performance,and ageing resistance property of the coated spherical propellant were systematically investigated by,Fourier transforms infrared spectroscopy(FTIR),Micro confocal raman spectrometer,field scanning electron microscopy(SEM),dynamic vapor adsorption techniques,and closed bomb test,confirming the surface core-shell structure and the tightly bonded interfacial structure of coated spherical propellant.Meanwhile,the coated spherical propellant has good hygroscopic,excellent progressive burning and long storage stability.
文摘For the production of reactive polyurethane cross-linkinger and curing agents, 2, 4-diisocyanate toluene (TDI) terpolymer, which possesses the rigid structures of hexatomic ring and three reactive functional groups, was synthesized and characterized by the Fourier transform infrared (FFIR), the gel permeation chromatography (GPC) and the chemical analysis methods. The reaction conditions were studied and optimized. A tracking research on the polymerization process of TDI was taken by using the GPC. The formation processes of the terpolymer, oligomers and higher-polymers were also dealt with. Results show that the TDI terpolymer can be prepared in the presence of Cat-3 catalyst and at the reaction temperature of (60 ±2)℃. The reaction time is short, its outcomes have narrow molecular weights distribution, namely molecular weights from 530 to 550, Mw/Mn =1.10, and the mass fraction of NCO is (25. 0 ± 0. 5)%. With the reaction time prolonging, however, TDI can be further higher-polymedzed to form higher-polymers. Benzoyl chloride (0. 4%, mass fraction), as the stabilizing agent, can effectively inhibit the occurrence of higher-polymerization. The obtained TDI terpolymer can be stable for more than half a year.
基金the National Natural Science Foundation of China[grant numbers 31660456].
文摘We determined the effects of different pre-freezing temperatures (−20℃ and −80℃) on the freeze-drying survival rate and stability during room temperature storage of Lactiplantibacillus plantarum LIP-1. The underlying mechanisms of survival and stability were also assessed. The freeze-drying survival rate and stability during room temperature storage of Lactiplantibacillus plantarum LIP-1 was significantly higher in the −80℃ than −20℃ group (p <0.05). Regarding the underlying mechanism, compared with the −20℃ group, the −80℃ group had a lower level of intracellular reactive oxygen species, lower degree of oxidation of fatty acids in the cell membrane, high integrity and fluidity of the cell membrane during freeze-drying and room temperature storage, and a significantly higher freeze-drying survival rate and storage stability (p<0.05). This study provides reference data that could help improve the freeze-drying survival rate and stability of probiotics during room temperature storage.
文摘In this paper,a kind of wall fabric’s surface treatment agent modified with nonionic surfactant was reported.This surface treatment agent was prepared by using nano tourmaline powder dispersion in water with surfactant as dispersants by sand milling.Under the influence of different dispersants,the negative ions releasing amount of functional wall fabrics,the milling process and the storage stability of nano tourmaline powder dispersion were discussed.The results showed that nano tourmaline powder dispersion achieved the smallest average diameter of 44 nm and had best storage stability that the average diameter maintained below 200 nm in 17 days when the addition amount of dispersant was 20 percent of the tourmaline powders’weight.What is more,the quantity of negative ion releasing achieved 6500 ion/cm3 when addition amount of dispersant was 30 percent.This technique could be used to strengthen productivity of nano tourmaline powder dispersion.
基金Projects(51838001,51878070,51908069)supported by the National Natural Science Foundation of China。
文摘In this paper,organic montmorillonite(OMMT)was added into crumb rubber modified asphalt(CRMA)to improve its high temperature performance,anti-aging performance and storage stability.The effects of different OMMT content on properties of CRMA were studied.The rutting factor obtained by dynamic shear rheological(DSR)test was adopted to evaluate the high-temperature performance.The creep stiffness and m value determined by the bending beam rheometer(BBR)test were employed to evaluate the low-temperature performance.The softening point,ductility,rutting factor before and after rolling thin film ovens test(RTFOT)and pressure aging vessel test(PAV)were compared to characterize the aging properties.Moreover,the segregation test after being reserved for 48 h and 7 d was conducted,and the softening point and rutting factor of upper and lower layers of segregation pipe were adopted to evaluate the storage stability.The results indicated that the high-temperature performance and anti-aging performance were developed with the increasing content of OMMT,while the low-temperature performance deteriorated.The storage stability was improved with the increasing content of OMMT before the content exceeded 4%,after which the storage stability declined.Taking account of all factors,it is suggested that the optimum content of OMMT is 3%−4%.
文摘Biodiesel(fatty acid alkyl esters),an alternate to fossil fuel,has the tendency of autoxidation and hence requires antioxidants for long term storage.The influence of synthetic and natural antioxidants on the oxidative stability was analysed for fresh FAMEs(fatty acid methyl esters)obtained from hevea brasiliensis at 140 C.Higher activity was observed for synthetic antioxidants following the order of GA】BHT】DTBP】Q】GT-M】PH-M】GT-C,whereas the oxidative stability of stored FAMEs samples measured at 110 C reveals a nearly inverse trend.Storage stability was tested for the FAMEs obtained from hevea brasiliensis stored at 30 C,after addition of synthetic and natural antioxidants—butylated hydroxytoluene(BHT),2,6-di-tert-butylphenol(DTBP),quercetin(Q),gallic acid(GA),methanol extracts from green tea(GTM),pomegranate hull(PH-M),and chloroform extract of green tea(GT-C).Antioxidant activities above 1500 ppm was in the order of DTBP】BHT】GA】GT-C】GT-M】Q】PH-M.Synthetic antioxidants have been found more efficient to improve the storage stability of FAMEs obtained from hevea brasiliensis.DTBP in particular has the highest protection factor.
基金financially supported by the Nature Science Foundation of Hubei Province (2018CFB269)
文摘Evidences show that the storage period greatly affects the quality of yogurt.In this study,three types of yogurt:control yogurt(CY),non-hydrolyzed potato powder yogurt(PPY)and enzymatically hydrolyzed potato powder yogurt(EHPPY)were prepared at 42℃ for 5 h and stored for 28 days at 4℃.The yogurts were evaluated for quality characteristics at different storage periods.Negligible differences in pH values,titratable acidities and viable counts were detected in all three types of yogurt during storage.However,compared to other yogurts,EHPPY exhibited desirable water holding capacity,throughout the storage period.Apart from this,sensory properties and antioxidant activities(2-diphenyl-1-picryl-hydrazyl(DPPH)free radical scavenging activity and ferric reducing antioxidant power(FRAP))of EHPPY were also significantly improved during the storage period.Furthermore,the storage(G’)and loss(G”)modulus of PPY,EHPPY were lower than CY at 4℃ while a hysteresis loop was shown by all yogurts at the temperature range of 4-50℃ indicating higher G’(elasticity)than G”(viscosity).Based on our findings,EHPP could be an important functional ingredient in improving the quality and storage stability of yogurt for its production at an industrial level.