A kind of novel shape-stabilized phase change material （SSPCM） was prepared by using a melting intercalation technique. This kind of SSPCM was made of lauric acid （LA） as a phase change material and organophilic m...A kind of novel shape-stabilized phase change material （SSPCM） was prepared by using a melting intercalation technique. This kind of SSPCM was made of lauric acid （LA） as a phase change material and organophilic montmorillonite （OMMT） as a support material. And the thermal properties and morphology of the SSPCM were characterized by X-ray diffraction （XRD）, transmission electron microscope （TEM）, scanning electronic microscope （SEM）, scanning calorimeter （DSC）, and differential thermal cravimetry （TG）. The DSC result shows that the phase change temperature of the SSPCM is close to that of LA, and its latent heat is equivalent to that of the calculated value based on the mass ratio of LA measured by TG. The XRD, SEM and TEM results demonstrate that the LA intercalates into the silicate layers of the OMMT, thus forming a typically intercalted hybrid, which can restrict the molecular chain of the LA within the structure of OMMT at high temperature. And consequently SSPCM can keep its solid state during its solid-liquid phase change processing.展开更多
This paper reported that a way of preparing superoxide dismutase (SOD) modified by lauric acid (LA-SOD) and study on stability of LA-SOD. The results showed that LA-SOD had high specific activity, high stability and h...This paper reported that a way of preparing superoxide dismutase (SOD) modified by lauric acid (LA-SOD) and study on stability of LA-SOD. The results showed that LA-SOD had high specific activity, high stability and high rate of recovery. The stability of LA-SOD in temperature, pH and human gastric juice was much higher than that of natural SOD. Because LA-SOD is kept for a long time at room temperature, it can widen the applied range of SOD and bring out considerable benificial results both in society and economy.展开更多
A novel route for the synthesis of alumina nanospheres was reported by a surfactant-governed approach in the presence of lauric acid.The products were characterized using X-ray diffraction （XRD）,scanning electron mi...A novel route for the synthesis of alumina nanospheres was reported by a surfactant-governed approach in the presence of lauric acid.The products were characterized using X-ray diffraction （XRD）,scanning electron microscope （SEM） and N2 adsorption-desorption techniques.The results show that the produced alumina nanospheres possess uniform nanosphere sizes ranging from 80 120 nm,and high surface area of 550 m2/g.It suggests that the synthesized alumina nanospheres are formed through self-assembly of surfactant/alumina species complex in 1-propanol system.展开更多
Corn cob is a naturally renewable material with developed micropore and hydrophobic characteristics, which enables it to show good oil adsorption capacity. In order to improve oil adsorption capacity, corn cob was mod...Corn cob is a naturally renewable material with developed micropore and hydrophobic characteristics, which enables it to show good oil adsorption capacity. In order to improve oil adsorption capacity, corn cob was modified with lauric acid and ethanediol. The structure of raw and modified corn cob was investigated using Fourier transform infrared(FTIR) spectroscopy, scanning electron microscopy(SEM), Brunauer-Emmett-Teller(BET) method, thermogravimetric analysis(TGA) and Ze Ta potential analyzer. The effects of p H level, adsorption time, adsorbent dosage, and initial oil concentration on oil absorbency of corn cob were studied. The results indicate that the modification significantly improved the lipophilicity of corn cob, making the modified corn cob with much better adsorption capacity on oil absorbency. Compared with raw corn cob, the maximum saturated adsorption capacity of modified corn cob is 16.52 mg/g at p H 5, and the increasing percentage is found to be 141%, which indicates that the modification causes a better adsorption capacity for oil removal. In addition, due to high oil adsorption capacity, affordable price and low secondary pollution, the modified corn cob could be considered promising alternative for the traditional oil adsorbent to clean up the emulsified oily water.展开更多
Commercially processed foods become contaminated with Listeria monocytogenes in post-processing environments where favorable conditions help the bacteria thrive. The US Food and Drug Administration has approved Lauric...Commercially processed foods become contaminated with Listeria monocytogenes in post-processing environments where favorable conditions help the bacteria thrive. The US Food and Drug Administration has approved Lauric arginate (LAE) as generally recognized as safe (GRAS) for certain food applications. This study evaluated the efficacy of Mirenat-N (LAE dissolved in food-grade propylene glycol) against L. monocytogenes on food contact surfaces. A three-strain cocktail of L. monocytogenes was used to inoculate 24 polished stainless steel coupons with three treatments, 100 ppm and 200 ppm solutions of LAE and water (control);two sub-treatments of high (6 log CFU/ml) and low (4 log CFU/ml) inoculum levels;and two contact times of 5 and 15 min. Attached bacteria were dislodged by vortexing coupons for 1 min with 20 g of 3-mm solid glass beads in 10 ml of 0.1% peptone diluent, and bacterial populations were calculated by plating onto modified oxford medium (MOX) and thin agar layer MOX (TALMOX). The 100 ppm treatment showed average reductions of 1.38 and 2.57 log CFU/coupon at the low inoculum level and 0.37 and 0.62 log CFU/coupon at high inoculum levels, after 5 and 15 min exposure, respectively. For 200 ppm at the high inoculum level, 1.23 and 1.88 log CFU/coupon reductions were seen for 5 and 15 min, respectively;the low inoculum level at 5 and 15 min exposure showed reductions of ≤1.5 log CFU/coupon. The 100 ppm LAE treatment was more effective at low inoculum levels for 5 and 15 min contact times and may be used to control low levels of contamination of L. monocytogenes on food contact surfaces.展开更多
Lauric acid(LA)has the possibility to improve milk production in dairy cows by improving mammary gland development,however,the mechanism by which it might regulate mammary gland development is unclear.The influence of...Lauric acid(LA)has the possibility to improve milk production in dairy cows by improving mammary gland development,however,the mechanism by which it might regulate mammary gland development is unclear.The influence of LA on milk production,nutrient digestibility and the expression of proteins related to mammary gland development in dairy cows were evaluated.Forty primiparous Holstein dairy cows were divided into 4 groups in a randomized block design.Four treatments included the control(0 g/d LA per cow),low-LA(100 g/d LA per cow),medium-LA(200 g/d LA per cow),and high-LA(300 g/d LA per cow).Yields of milk,fat-corrected milk,and energy-corrected milk quadratically increased(P<0.05),and yield and content of milk fat linearly increased(P<0.05)with LA supplementation.Percentages of C12:0,C18:1 and C20:1 fatty acids in milk fat linearly increased(P<0.05),but that of C16:0 fatty acid linearly decreased(P=0.046).Supplementation of LA led to a linear and quadratical increase(P<0.05)in digestibility of dry matter,organic matter,neutral detergent fibre and acid detergent fibre,and ruminal total volatile fatty acid concentration but a linear reduction(P=0.018)in the ratio of acetate to propionate.The enzymatic activities of ruminal pectinase,xylanase,andα-amylase,and populations of total bacteria and anaerobic fungi increased linearly(P<0.05),while populations of total protozoa and methanogens decreased linearly(P<0.05)with increased LA addition.Following LA addition,blood glucose,triglyceride,estradiol,prolactin,and insulin-like growth factor 1 concentrations increased linearly(P<0.05)and albumin and total protein concentrations increased quadratically(P<0.05).Moreover,addition of 200 g/d LA promoted(P<0.05)the expression of protein involved in mammary gland development and fatty acids synthesis.These results suggested that LA addition enhanced milk production and fatty acids synthesis by stimulating nutrient digestion,the expression of proteins associated with milk fat synthesis and mammary gland development.展开更多
The phase behaviour of the middle-phase microemulsion for the quaternary system lauric-N-methylglucamide （MEGA-12）/n-butanollalkane/water has been studied with Winsor type, δ-γ, fishlike and novel ε-β fishlike p...The phase behaviour of the middle-phase microemulsion for the quaternary system lauric-N-methylglucamide （MEGA-12）/n-butanollalkane/water has been studied with Winsor type, δ-γ, fishlike and novel ε-β fishlike phase diagrams. A series of phase inversions Winsor I （2）→Ⅲ（3）→Ⅱ （ 2 ） were observed for the three kinds of phase diagrams. The phase types, the phase volumes and the range of alcohol concentrations from the beginning to the end of the middle-phase microemulsion were obtained from Winsor phase diagram. From δ-γ, fishlike phase diagram, the physicochemical parameters, such as the mass fraction of n-butanol in the hydrophile-lipophile balanced inteffacial layer, A^s, the coordinates of the start and end points of the middle-phase microemulsion, and the solubilities of MEGA-12 and n-butanol in alkane phase were calculated. The novel ε-β fishlike phase diagram was also presented. From this kind of diagram, the above experimental phenomena were observed and the physicochemical parameters were calculated precisely. The novel fishlike phase diagram has advantages over the Winsor and δ-γ fishlike phase diagrams in the evaluation of the solubilization power of the microemulsion and calculation of the related physicochemical parameters.展开更多
This work presents the results of tribological investigations of lubricating substances composed of water and a nonionic surfactant:lauric acid random copolyether(LPE),as additive.At the current stage of investigation...This work presents the results of tribological investigations of lubricating substances composed of water and a nonionic surfactant:lauric acid random copolyether(LPE),as additive.At the current stage of investigation,aqueous solutions with LPE additives are prepared and subsequently the lowering friction and reducing wear behaviors are tested by means of friction/wear tester,in conjunction with that the film forming properties experiments are carried out with a nanoscale film thickness measure apparatus.The contact is under condition of steel-steel tribo-pair.The results show that the coefficient of friction measured decreases considerably to about over 60%relative to water.The film thickness data of friction process lubricated by aqueous solutions with LPE added show that the lubrication is in boundary lubrication regime.The results indicate that aqueous solutions with LPE added can be used to improve the lubricity and they may be applied to real tribological systems.展开更多
单一脂肪酸的相变温度普遍较高且易泄漏,不能满足其作为相变材料对夏季建筑空调能耗调节的需求。本工作基于真实溶剂类导体屏蔽模型(conductor-like screening model for real solvents,COSMO-RS),采用COSMOthermX软件对7种中链脂肪酸...单一脂肪酸的相变温度普遍较高且易泄漏,不能满足其作为相变材料对夏季建筑空调能耗调节的需求。本工作基于真实溶剂类导体屏蔽模型(conductor-like screening model for real solvents,COSMO-RS),采用COSMOthermX软件对7种中链脂肪酸和10种长链脂肪酸两两组合的136种二元低共熔脂肪酸进行设计计算,筛选预测其共熔温度与摩尔比。进而将最优组合作为芯材,三聚氰胺-尿素-甲醛树脂(MUF)为壁材,通过原位聚合法制备相变微胶囊,系统地探讨不同工艺条件(芯壁比、反应温度、反应时间和反应转速等)对该微胶囊热物理性能的影响。结果表明:COSMO-RS模型可以直观地判断材料氢键供体(hydrogen bond donor,HBD)与受体(hydrogen bond acceptor,HBA)之间的关系,最优组合月桂酸(lauric acid,LA)与肉豆蔻酸(myristic acid,MA)摩尔比为0.66∶0.34的LA-MA(LM)理论共熔温度(33.25℃)与实验结果(33.1℃)相似度达98.08%;在芯壁比2∶1、反应时间3 h、反应温度80℃、搅拌转速200 r/min的条件下,MUF对芯材LM的包覆效率为61.37%,较好地解决了泄漏问题,对降低建筑空调制冷能耗具有潜在的应用价值。展开更多
文摘A kind of novel shape-stabilized phase change material （SSPCM） was prepared by using a melting intercalation technique. This kind of SSPCM was made of lauric acid （LA） as a phase change material and organophilic montmorillonite （OMMT） as a support material. And the thermal properties and morphology of the SSPCM were characterized by X-ray diffraction （XRD）, transmission electron microscope （TEM）, scanning electronic microscope （SEM）, scanning calorimeter （DSC）, and differential thermal cravimetry （TG）. The DSC result shows that the phase change temperature of the SSPCM is close to that of LA, and its latent heat is equivalent to that of the calculated value based on the mass ratio of LA measured by TG. The XRD, SEM and TEM results demonstrate that the LA intercalates into the silicate layers of the OMMT, thus forming a typically intercalted hybrid, which can restrict the molecular chain of the LA within the structure of OMMT at high temperature. And consequently SSPCM can keep its solid state during its solid-liquid phase change processing.
文摘This paper reported that a way of preparing superoxide dismutase (SOD) modified by lauric acid (LA-SOD) and study on stability of LA-SOD. The results showed that LA-SOD had high specific activity, high stability and high rate of recovery. The stability of LA-SOD in temperature, pH and human gastric juice was much higher than that of natural SOD. Because LA-SOD is kept for a long time at room temperature, it can widen the applied range of SOD and bring out considerable benificial results both in society and economy.
基金supported by the State Key Basic Research Program of China(2006CB202505)the National Natural Science Foundation of China(20806093)
文摘A novel route for the synthesis of alumina nanospheres was reported by a surfactant-governed approach in the presence of lauric acid.The products were characterized using X-ray diffraction （XRD）,scanning electron microscope （SEM） and N2 adsorption-desorption techniques.The results show that the produced alumina nanospheres possess uniform nanosphere sizes ranging from 80 120 nm,and high surface area of 550 m2/g.It suggests that the synthesized alumina nanospheres are formed through self-assembly of surfactant/alumina species complex in 1-propanol system.
基金Project(51174017)supported by the National Natural Science Foundation of China
文摘Corn cob is a naturally renewable material with developed micropore and hydrophobic characteristics, which enables it to show good oil adsorption capacity. In order to improve oil adsorption capacity, corn cob was modified with lauric acid and ethanediol. The structure of raw and modified corn cob was investigated using Fourier transform infrared(FTIR) spectroscopy, scanning electron microscopy(SEM), Brunauer-Emmett-Teller(BET) method, thermogravimetric analysis(TGA) and Ze Ta potential analyzer. The effects of p H level, adsorption time, adsorbent dosage, and initial oil concentration on oil absorbency of corn cob were studied. The results indicate that the modification significantly improved the lipophilicity of corn cob, making the modified corn cob with much better adsorption capacity on oil absorbency. Compared with raw corn cob, the maximum saturated adsorption capacity of modified corn cob is 16.52 mg/g at p H 5, and the increasing percentage is found to be 141%, which indicates that the modification causes a better adsorption capacity for oil removal. In addition, due to high oil adsorption capacity, affordable price and low secondary pollution, the modified corn cob could be considered promising alternative for the traditional oil adsorbent to clean up the emulsified oily water.
文摘Commercially processed foods become contaminated with Listeria monocytogenes in post-processing environments where favorable conditions help the bacteria thrive. The US Food and Drug Administration has approved Lauric arginate (LAE) as generally recognized as safe (GRAS) for certain food applications. This study evaluated the efficacy of Mirenat-N (LAE dissolved in food-grade propylene glycol) against L. monocytogenes on food contact surfaces. A three-strain cocktail of L. monocytogenes was used to inoculate 24 polished stainless steel coupons with three treatments, 100 ppm and 200 ppm solutions of LAE and water (control);two sub-treatments of high (6 log CFU/ml) and low (4 log CFU/ml) inoculum levels;and two contact times of 5 and 15 min. Attached bacteria were dislodged by vortexing coupons for 1 min with 20 g of 3-mm solid glass beads in 10 ml of 0.1% peptone diluent, and bacterial populations were calculated by plating onto modified oxford medium (MOX) and thin agar layer MOX (TALMOX). The 100 ppm treatment showed average reductions of 1.38 and 2.57 log CFU/coupon at the low inoculum level and 0.37 and 0.62 log CFU/coupon at high inoculum levels, after 5 and 15 min exposure, respectively. For 200 ppm at the high inoculum level, 1.23 and 1.88 log CFU/coupon reductions were seen for 5 and 15 min, respectively;the low inoculum level at 5 and 15 min exposure showed reductions of ≤1.5 log CFU/coupon. The 100 ppm LAE treatment was more effective at low inoculum levels for 5 and 15 min contact times and may be used to control low levels of contamination of L. monocytogenes on food contact surfaces.
基金funded by the Education Department of Shanxi Province,Excellent Doctor Work Award Fund Research Project[SXYBKY2018036]Modern Agro industry Technology Research System of Shanxi Province (2023CYJSTX13).
文摘Lauric acid(LA)has the possibility to improve milk production in dairy cows by improving mammary gland development,however,the mechanism by which it might regulate mammary gland development is unclear.The influence of LA on milk production,nutrient digestibility and the expression of proteins related to mammary gland development in dairy cows were evaluated.Forty primiparous Holstein dairy cows were divided into 4 groups in a randomized block design.Four treatments included the control(0 g/d LA per cow),low-LA(100 g/d LA per cow),medium-LA(200 g/d LA per cow),and high-LA(300 g/d LA per cow).Yields of milk,fat-corrected milk,and energy-corrected milk quadratically increased(P<0.05),and yield and content of milk fat linearly increased(P<0.05)with LA supplementation.Percentages of C12:0,C18:1 and C20:1 fatty acids in milk fat linearly increased(P<0.05),but that of C16:0 fatty acid linearly decreased(P=0.046).Supplementation of LA led to a linear and quadratical increase(P<0.05)in digestibility of dry matter,organic matter,neutral detergent fibre and acid detergent fibre,and ruminal total volatile fatty acid concentration but a linear reduction(P=0.018)in the ratio of acetate to propionate.The enzymatic activities of ruminal pectinase,xylanase,andα-amylase,and populations of total bacteria and anaerobic fungi increased linearly(P<0.05),while populations of total protozoa and methanogens decreased linearly(P<0.05)with increased LA addition.Following LA addition,blood glucose,triglyceride,estradiol,prolactin,and insulin-like growth factor 1 concentrations increased linearly(P<0.05)and albumin and total protein concentrations increased quadratically(P<0.05).Moreover,addition of 200 g/d LA promoted(P<0.05)the expression of protein involved in mammary gland development and fatty acids synthesis.These results suggested that LA addition enhanced milk production and fatty acids synthesis by stimulating nutrient digestion,the expression of proteins associated with milk fat synthesis and mammary gland development.
基金Project supported by the Natural Science Foundation of Shandong Province （No. Y2003B01）.
文摘The phase behaviour of the middle-phase microemulsion for the quaternary system lauric-N-methylglucamide （MEGA-12）/n-butanollalkane/water has been studied with Winsor type, δ-γ, fishlike and novel ε-β fishlike phase diagrams. A series of phase inversions Winsor I （2）→Ⅲ（3）→Ⅱ （ 2 ） were observed for the three kinds of phase diagrams. The phase types, the phase volumes and the range of alcohol concentrations from the beginning to the end of the middle-phase microemulsion were obtained from Winsor phase diagram. From δ-γ, fishlike phase diagram, the physicochemical parameters, such as the mass fraction of n-butanol in the hydrophile-lipophile balanced inteffacial layer, A^s, the coordinates of the start and end points of the middle-phase microemulsion, and the solubilities of MEGA-12 and n-butanol in alkane phase were calculated. The novel ε-β fishlike phase diagram was also presented. From this kind of diagram, the above experimental phenomena were observed and the physicochemical parameters were calculated precisely. The novel fishlike phase diagram has advantages over the Winsor and δ-γ fishlike phase diagrams in the evaluation of the solubilization power of the microemulsion and calculation of the related physicochemical parameters.
基金supported by the Fundamental Research Funds for the Central Universities(Grant No.2013JBZ015)
文摘This work presents the results of tribological investigations of lubricating substances composed of water and a nonionic surfactant:lauric acid random copolyether(LPE),as additive.At the current stage of investigation,aqueous solutions with LPE additives are prepared and subsequently the lowering friction and reducing wear behaviors are tested by means of friction/wear tester,in conjunction with that the film forming properties experiments are carried out with a nanoscale film thickness measure apparatus.The contact is under condition of steel-steel tribo-pair.The results show that the coefficient of friction measured decreases considerably to about over 60%relative to water.The film thickness data of friction process lubricated by aqueous solutions with LPE added show that the lubrication is in boundary lubrication regime.The results indicate that aqueous solutions with LPE added can be used to improve the lubricity and they may be applied to real tribological systems.
文摘单一脂肪酸的相变温度普遍较高且易泄漏,不能满足其作为相变材料对夏季建筑空调能耗调节的需求。本工作基于真实溶剂类导体屏蔽模型(conductor-like screening model for real solvents,COSMO-RS),采用COSMOthermX软件对7种中链脂肪酸和10种长链脂肪酸两两组合的136种二元低共熔脂肪酸进行设计计算,筛选预测其共熔温度与摩尔比。进而将最优组合作为芯材,三聚氰胺-尿素-甲醛树脂(MUF)为壁材,通过原位聚合法制备相变微胶囊,系统地探讨不同工艺条件(芯壁比、反应温度、反应时间和反应转速等)对该微胶囊热物理性能的影响。结果表明:COSMO-RS模型可以直观地判断材料氢键供体(hydrogen bond donor,HBD)与受体(hydrogen bond acceptor,HBA)之间的关系,最优组合月桂酸(lauric acid,LA)与肉豆蔻酸(myristic acid,MA)摩尔比为0.66∶0.34的LA-MA(LM)理论共熔温度(33.25℃)与实验结果(33.1℃)相似度达98.08%;在芯壁比2∶1、反应时间3 h、反应温度80℃、搅拌转速200 r/min的条件下,MUF对芯材LM的包覆效率为61.37%,较好地解决了泄漏问题,对降低建筑空调制冷能耗具有潜在的应用价值。
