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
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
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 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 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
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
Waste polyethylene packaging （WPE） was used to modify asphalt, and hot storage stability of the modified asphalt was studied in this paper. The morphological change and component loss of WPE modified asphalt were ch...Waste polyethylene packaging （WPE） was used to modify asphalt, and hot storage stability of the modified asphalt was studied in this paper. The morphological change and component loss of WPE modified asphalt were characterized by fluorescence microscopy, Fourier transform infrared spectroscopy （FT-IR）, differential scanning calorimetry （DSC）, thermogravimetry （TG） and isolation testing. In addition, the mechanism of the hot storage stability of WPE modified asphalt was discussed. The results showed that the modification of asphalt with WPE was a physical process. It was found that the filament or partly network-like structure formed in the modified asphalt system was beneficial to improving the hot storage stability. Moreover, the addition of WPE resulted in a decrease in both the light components volatilization and the macromolecules decomposition of asphalt. It was demonstrated that when the content of WPE in matrix asphalt was less than 10 wt%, the service performances of modified asphalt could be better.展开更多
Unlike fresh farm produce,processed fruits and vegetables such as sun dried tomatoes can be categorized as ambient temperature shelf stable products.However,large quantities of these products yet easily go bad most es...Unlike fresh farm produce,processed fruits and vegetables such as sun dried tomatoes can be categorized as ambient temperature shelf stable products.However,large quantities of these products yet easily go bad most especially when the appropriate conditions for their storage are not offered.To minimize these losses,it is important to know and exploit the optimum environmental conditions and moisture content range for the storage of the products.The present study through systematic theoretical assertions employed by other researchers on other crops seeks to establish the storage stability of dried tomato slice at three probable temperatures of 10,30 and 45°C.Results showed that in this temperature range,upper limit moisture content varied between 6%-7.5%and 6.5%-8.3%d.b.for adsorption and desorption,respectively.The corresponding lower limit moisture contents varied between 4.29%-5.52%and 5.15%-6.29%d.b.In order to minimize moisture migration into or out of dried tomato slice during storage,the study revealed that the product should be stored within 29%-62%relative humidity.展开更多
Effects of different additives(sucrose and maltodextrin)on storage stability of colostral whey(CW)powders packaged in aluminium-laminated polyethylene pouches were investigated under different storage conditions(4℃an...Effects of different additives(sucrose and maltodextrin)on storage stability of colostral whey(CW)powders packaged in aluminium-laminated polyethylene pouches were investigated under different storage conditions(4℃and 40%-70%relative humidity(RH),25℃and 50%RH,and 50℃and 20%-60%RH).All the samples stored under 50℃and 20%-60%RH showed the highest levels of lipid oxidation,Maillard reaction,proteolysis,and color difference,and the lowest immunoglobulin G(IgG)retention.Moisture contents showed an increase trend with increasing RH.Addition of sucrose into CW powders increased water adsorption capacity and Maillard reaction,whereas addition of maltodextrin showed the opposite effects.Maltodextrin as drying aids was suitable for keeping quality during storage.Sucrose did not clearly play any roles in protecting denaturation of IgG during 90-day storage.The low storage temperature and RH were helpful for keeping storage stability of CW powders with different additives.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
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
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
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 underground water-sealed storage technique is critically important and generally accepted for the national energy strategy in China. Although several small underground water-sealed oil storage caverns have been bu...The underground water-sealed storage technique is critically important and generally accepted for the national energy strategy in China. Although several small underground water-sealed oil storage caverns have been built in China since the 1970s, there is still a lack of experience for large-volume underground storage in complicated geological conditions. The current design concept of water curtain system and the technical instruction for system operation have limitations in maintaining the stability of surrounding rock mass during the construction of the main storage caverns, as well as the long-term stability. Although several large-scale underground oil storage projects are under construction at present in China, the design concepts and construction methods, especially for the water curtain system, are mainly based on the ideal porosity medium flow theory and the experiences gained from the similar projects overseas. The storage projects currently constructed in China have the specific features such as huge scale, large depth, multiple-level arrangement, high seepage pressure, complicated geological conditions, and high in situ stresses, which are the challenging issues for the stability of the storage caverns. Based on years’ experiences obtained from the first large-scale （millions of cubic meters） underground water-sealed oil storage project in China, some design and operation problems related to water curtain system during project construction are discussed. The drawbacks and merits of the water curtain system are also presented. As an example, the conventional concept of “filling joints with water” is widely used in many cases, as a basic concept for the design of the water curtain system, but it is immature. In this paper, the advantages and disadvantages of the conventional concept are pointed out, with respect to the long-term stability as well as the safety of construction of storage caverns. Finally, new concepts and principles for design and construction of the underground water-sealed oil storage caverns are proposed.展开更多
Large underground caverns are commonly used in variety of applications. In many cases, because of the geomechanical limitations of dimensions and requirement of high volume, several parallel caverns are used. Plastic ...Large underground caverns are commonly used in variety of applications. In many cases, because of the geomechanical limitations of dimensions and requirement of high volume, several parallel caverns are used. Plastic zone integration requires a larger rock pillar distance of theses adjacent caverns while eco- nomic and access reasons require smaller distance. In lran many underground projects are located in West and South West, Asmari formation covers a large part of these regions. The stability of underground spaces that are constructed or will be constructed in this formation has been investigated. A proper cross section based on plastic analysis and a stability criterion has been proposed for each region. Finally, in each case, allowable rock pillar between adjacent caverns with similar dimension was determined with two methods （numerical analysis and fire service law）. Results show that Fire Service Law uses a very con- servative safety factor and it was proposed to use a correction factor for allowable distance based on application of underground space.展开更多
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 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.
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support provided by the National Natural Science Foundation of China(Grant Nos. 51002118 and 51172180)Shaanxi Programs for Science and Technology Development(2011)+1 种基金Xi'an Programs for Industrial Applications(Grant No.CXY1129-3)the Beilin District Programs for Science and Technology Development(Grant No. GX1109)
文摘Waste polyethylene packaging （WPE） was used to modify asphalt, and hot storage stability of the modified asphalt was studied in this paper. The morphological change and component loss of WPE modified asphalt were characterized by fluorescence microscopy, Fourier transform infrared spectroscopy （FT-IR）, differential scanning calorimetry （DSC）, thermogravimetry （TG） and isolation testing. In addition, the mechanism of the hot storage stability of WPE modified asphalt was discussed. The results showed that the modification of asphalt with WPE was a physical process. It was found that the filament or partly network-like structure formed in the modified asphalt system was beneficial to improving the hot storage stability. Moreover, the addition of WPE resulted in a decrease in both the light components volatilization and the macromolecules decomposition of asphalt. It was demonstrated that when the content of WPE in matrix asphalt was less than 10 wt%, the service performances of modified asphalt could be better.
文摘Unlike fresh farm produce,processed fruits and vegetables such as sun dried tomatoes can be categorized as ambient temperature shelf stable products.However,large quantities of these products yet easily go bad most especially when the appropriate conditions for their storage are not offered.To minimize these losses,it is important to know and exploit the optimum environmental conditions and moisture content range for the storage of the products.The present study through systematic theoretical assertions employed by other researchers on other crops seeks to establish the storage stability of dried tomato slice at three probable temperatures of 10,30 and 45°C.Results showed that in this temperature range,upper limit moisture content varied between 6%-7.5%and 6.5%-8.3%d.b.for adsorption and desorption,respectively.The corresponding lower limit moisture contents varied between 4.29%-5.52%and 5.15%-6.29%d.b.In order to minimize moisture migration into or out of dried tomato slice during storage,the study revealed that the product should be stored within 29%-62%relative humidity.
基金Department of Science and Technology of China under National Key Technology R&D Program(2013BAD18B02)Minhang District Cooperative Projects(2012MH156)to provide the financial support.
文摘Effects of different additives(sucrose and maltodextrin)on storage stability of colostral whey(CW)powders packaged in aluminium-laminated polyethylene pouches were investigated under different storage conditions(4℃and 40%-70%relative humidity(RH),25℃and 50%RH,and 50℃and 20%-60%RH).All the samples stored under 50℃and 20%-60%RH showed the highest levels of lipid oxidation,Maillard reaction,proteolysis,and color difference,and the lowest immunoglobulin G(IgG)retention.Moisture contents showed an increase trend with increasing RH.Addition of sucrose into CW powders increased water adsorption capacity and Maillard reaction,whereas addition of maltodextrin showed the opposite effects.Maltodextrin as drying aids was suitable for keeping quality during storage.Sucrose did not clearly play any roles in protecting denaturation of IgG during 90-day storage.The low storage temperature and RH were helpful for keeping storage stability of CW powders with different additives.
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 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.
文摘The underground water-sealed storage technique is critically important and generally accepted for the national energy strategy in China. Although several small underground water-sealed oil storage caverns have been built in China since the 1970s, there is still a lack of experience for large-volume underground storage in complicated geological conditions. The current design concept of water curtain system and the technical instruction for system operation have limitations in maintaining the stability of surrounding rock mass during the construction of the main storage caverns, as well as the long-term stability. Although several large-scale underground oil storage projects are under construction at present in China, the design concepts and construction methods, especially for the water curtain system, are mainly based on the ideal porosity medium flow theory and the experiences gained from the similar projects overseas. The storage projects currently constructed in China have the specific features such as huge scale, large depth, multiple-level arrangement, high seepage pressure, complicated geological conditions, and high in situ stresses, which are the challenging issues for the stability of the storage caverns. Based on years’ experiences obtained from the first large-scale （millions of cubic meters） underground water-sealed oil storage project in China, some design and operation problems related to water curtain system during project construction are discussed. The drawbacks and merits of the water curtain system are also presented. As an example, the conventional concept of “filling joints with water” is widely used in many cases, as a basic concept for the design of the water curtain system, but it is immature. In this paper, the advantages and disadvantages of the conventional concept are pointed out, with respect to the long-term stability as well as the safety of construction of storage caverns. Finally, new concepts and principles for design and construction of the underground water-sealed oil storage caverns are proposed.
文摘Large underground caverns are commonly used in variety of applications. In many cases, because of the geomechanical limitations of dimensions and requirement of high volume, several parallel caverns are used. Plastic zone integration requires a larger rock pillar distance of theses adjacent caverns while eco- nomic and access reasons require smaller distance. In lran many underground projects are located in West and South West, Asmari formation covers a large part of these regions. The stability of underground spaces that are constructed or will be constructed in this formation has been investigated. A proper cross section based on plastic analysis and a stability criterion has been proposed for each region. Finally, in each case, allowable rock pillar between adjacent caverns with similar dimension was determined with two methods （numerical analysis and fire service law）. Results show that Fire Service Law uses a very con- servative safety factor and it was proposed to use a correction factor for allowable distance based on application of underground space.
