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Dietary supplemental coated essential oils and organic acids mixture improves growth performance and gut health along with reduces Salmonella load of broiler chickens infected with Salmonella Enteritidis 被引量:2
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作者 Zeqiong Hu Lin Liu +7 位作者 Fangshen Guo Jia Huang Jianing Qiao Ruichen Bi Jinyu Huang Kaichen Zhang Yuming Guo Zhong Wang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2023年第6期2554-2577,共24页
Background Reducing Salmonella infection in broiler chickens by using effective and safe alternatives to antibiotics is vital to provide safer poultry meat and minimize the emergence of drug-resistant Salmonella and t... Background Reducing Salmonella infection in broiler chickens by using effective and safe alternatives to antibiotics is vital to provide safer poultry meat and minimize the emergence of drug-resistant Salmonella and the spread of salmonellosis to humans.This study was to first evaluate the protective efficacy of feeding coated essential oils and organic acids mixture(EOA)on broiler chickens infected with Salmonella Enteritidis(S.Enteritidis,SE),and then its action mechanism was further explored.Methods A total of 4801-day-old Arbor Acres male chickens were randomly assigned into five treatments with six replicates,including non-challenged control fed with basal diet(A),SE-challenged control(B),and SE-infected birds fed a basal diet with 300 mg/kg of EOA(BL),500 mg/kg of EOA(BM)and 800 mg/kg of EOA(BH),respectively.All birds on challenged groups were infected with Salmonella Enteritidis on d 13.Results Feeding EOA showed a reversed ability on negative effects caused by SE infection,as evidenced by decreasing the feed conversion rate(FCR)and the ratio of villus height to crypt depth(VH/CD)(P<0.05),obviously decreasing intestinal and internal organs Salmonella load along with increasing cecal butyric acid-producing bacteria abundance(P<0.05).Moreover,supplemental different levels of EOA notably up-regulated claudin-1(CLDN-1),occludin(OCLN),zonula occludens-1(ZO-1),mucin-2(MUC-2),fatty acid binding protein-2(FABP-2),nuclear factor kappa-light-chainenhancer of activated B cells(NF-κB),myeloid differential protein-88(MyD88)and interleukin-6(IL-6)mRNA levels in the ileum of the infected chickens after challenge,whereas down-regulated toll-like receptor-4(TLR-4)mRNA levels(P<0.05).Linear discriminant analysis combined effect size measurements analysis(LEfSe)showed that the relative abundance of g_Butyricicoccus,g_Anaerotruncus and g_unclassified_f_Bacillaceae significantly was enriched in infected birds given EOA.Also,phylogenetic investigation of communities by reconstruction of unobserved states(PICRUSt)analysis showed that alpha-linolenic acid metabolism,fatty acid metabolism and biosynthesis of unsaturated fatty acids were significantly enriched in the EOA group.Conclusion Our data suggest that the essential oils and organic acids mixture can be used as an effective strategy to ameliorate and alleviate Salmonella Enteritidis infection in broilers. 展开更多
关键词 Broiler chickens Essential oils and organic acids mixture Gut health Salmonella Enteritidis
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Effect of confinement on the three-phase equilibrium of water-oil-CO_(2)mixtures in nanopores 被引量:3
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作者 Yi-Lei Song Shao-Hua Gu +3 位作者 Zhao-Jie Song Zhuo-Ya Zhang Xu-Ya Chang Jia Guo 《Petroleum Science》 SCIE CAS CSCD 2022年第1期203-210,共8页
Accurate characterization of fluid phase behavior is an important aspect of CO_(2) enhanced shale oil recovery.So far,however,there has been little discussion about the nanopore confinement effect,including adsorption... Accurate characterization of fluid phase behavior is an important aspect of CO_(2) enhanced shale oil recovery.So far,however,there has been little discussion about the nanopore confinement effect,including adsorption and capillarity on the phase equilibrium of water-oil-CO_(2) mixtures.In this study,an improved three-phase flash algorithm is proposed for calculating the phase behavior of water-oil-gas mixture on the basis of an extended Young-Laplace equation and a newly developed fugacity calculation model.The fugacity model can consider the effect of water-oil-gas adsorption on phase equilibrium.A water-Bakken oil-CO_(2) mixture is utilized to verify the accuracy of the flash algorithm and investigate the confinement effect.Results show that the confinement effect promotes the transfer of all components in the vapor phase to other phases,while the transfer of water,CO_(2),and lighter hydrocarbons is more significant.This leads to a large decrease,a large increase,and a small increase in the mole fraction of the vapor,oleic,and aqueous phases,respectively.When the confinement effect is considered,the density difference of vaporoleic phases decreases,and the interfacial tension of vapor-oleic phases decreases;however,the density difference of vapor-aqueous phases increases,the interfacial tension of vapor-aqueous phases still decreases. 展开更多
关键词 Three-phase behavior Water-oil-CO_(2)mixtures Nanopore confinement CO_(2)enhanced oil recovery Shale reservoirs
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Phase behavior of heavy oil-solvent mixture systems under reservoir conditions 被引量:1
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作者 Xiao-Fei Sun Zhao-Yao Song +2 位作者 Lin-Feng Cai Yan-Yu Zhang Peng Li 《Petroleum Science》 SCIE CAS CSCD 2020年第6期1683-1698,共16页
A novel experimental procedure was proposed to investigate the phase behavior of a solvent mixture(SM)(64 mol%CH4,8 mol%CO2,and 28 mol%C3 H8)with heavy oil.Then,a theoretical methodology was employed to estimate the p... A novel experimental procedure was proposed to investigate the phase behavior of a solvent mixture(SM)(64 mol%CH4,8 mol%CO2,and 28 mol%C3 H8)with heavy oil.Then,a theoretical methodology was employed to estimate the phase behavior of the heavy oil-solvent mixture(HO-SM)systems with various mole fractions of SM.The experimental results show that as the mole fraction of SM increases,the saturation pressures and swelling factors of the HO-SM systems considerably increase,and the viscosities and densities of the HO-SM systems decrease.The heavy oil is upgraded in situ via asphaltene precipitation and SM dissolution.Therefore,the solvent-enriched oil phase at the top layer of reservoirs can easily be produced from the reservoir.The aforementioned results indicate that the SM has promising application potential for enhanced heavy oil recovery via solvent-based processes.The theoretical methodology can accurately predict the saturation pressures,swelling factors,and densities of HO-SM systems with various mole fractions of SM,with average error percentages of1.77%for saturation pressures,0.07%for swelling factors,and 0.07%for densities. 展开更多
关键词 Heavy oil Solvent mixture PR-EOS Phase behavior Pressure-volume-temperature(PVT)
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Physical-Rheological Properties and Performances of Rejuvenated(Styrene-Butadiene-Styrene)Asphalt with Polymerized-MDI and Aromatic Oil
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作者 Ao Lu Ming Xiong +3 位作者 Chen Chen Liangjiang Li Haibei Tan Xiong Xu 《Fluid Dynamics & Materials Processing》 EI 2024年第7期1633-1646,共14页
Traditional asphalt rejuvenators,like aromatic oil(AO),are known to be effective in improving the low-temperature properties and fatigue performances of aged SBS(styrene-butadiene-styrene)modified asphalt(SBSMA)binder... Traditional asphalt rejuvenators,like aromatic oil(AO),are known to be effective in improving the low-temperature properties and fatigue performances of aged SBS(styrene-butadiene-styrene)modified asphalt(SBSMA)binders and mixtures.However,these rejuvenators inevitably compromise their high-temperature properties and deformation resistances because they dilute asphalt binder but do not fix the damaged structures of aged SBS.In this study,a highly-active chemical called polymerized 4,4-diphenylmethane diisocyanate(PMDI)was used to assist the traditional AO asphalt rejuvenator.The physical and rheological characteristics of rejuvenated SBSMA binders and the moisture-induced damage and rut deformation performances of corresponding mixtures were comparatively evaluated.The results showed that the increasing proportion of AO compromises the hightemperature property and hardness of aged SBSMA binder,and an appropriate amount of PMDI works to compensate such losses;3%rejuvenator at mass ratio of AO:PMDI=70:30 can have a rejuvenated SBSMA binder with a high-temperature performance similar to that of fresh binder,approximately at 71.4°C;the use of AO can help reduce the viscosity of PMDI rejuvenated SBSMA binder for improving its workability;PMDI can help improve the resistance of AO rejuvenated SBSMA binder to deformation,especially at elevated temperatures,through its chemical reactions with aged SBS;moisture induction can enhance the resistance to damage of rejuvenated mixtures containing AO/PMDI or only PMDI;and the rejuvenator with a mass ratio of AO:PMDI=70:30 can lead the rejuvenated mixture to meet the application requirement,with a rut depth of only 2.973 mm,although more PMDI can result in a higher resistance of rejuvenated mixtures to high-temperature deformation. 展开更多
关键词 Aged SBS modified asphalt polymerized 4 4-diphenylmethane diisocyanate aromatic oil physical properties rheological properties mixture performance
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Precipitation of Heavy Organics (Asphaltenes) from Crude Oil Residue Using Binary Mixtures of n-Alkanes
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作者 O. Achugasim I. E. Ekpo 《Advances in Chemical Engineering and Science》 2015年第1期96-101,共6页
Two solvent mixtures: n-pentane/n-hexane and n-heptane/n-octane at ten different percentage ratios were used to dissolve 2.5 g of vacuum distilled Anthan crude oil residue (500°C). The crude oil/n-alkane mixture ... Two solvent mixtures: n-pentane/n-hexane and n-heptane/n-octane at ten different percentage ratios were used to dissolve 2.5 g of vacuum distilled Anthan crude oil residue (500°C). The crude oil/n-alkane mixture in different conical flasks was stoppered, shaked mechanically and allowed to stand overnight. The resultant solution was subsequently filtered using a vacuum pump to afford the different weights of the residue (asphaltenes). The result of the weights of asphaltenes obtained at the different ratios of solvent mixtures showed that the highest amount of precipitate was obtained at 100% n-pentane solvent. Also there was a sharp increase in the amount of asphaltenes precipitated when the percentage ratio of n-pentane to n-hexane precipitant was 40:60 and when the ratio of n-heptane to n-octane precipitant was 30:70. A good understanding of the contribution of the different n-alkane solvents in the precipitation of asphaltenes is very necessary to flow assurance of crude oils in terms of solid precipitation. 展开更多
关键词 ASPHALTENES Precipitants N-HEPTANE N-OCTANE Crude oil Binary mixtures
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Blood Oxidant/Antioxidant Status in overfed Aging Rats: Comparative Effects of Sunflower and Olive-Linseed Mixture Oil Rich Diets
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作者 AYAD Amina MERZOUK Hafida +1 位作者 MERZOUK Sid Ahmed NARCE Michel 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第9期765-768,共4页
Obesity, one of the most common health problems, is associated with glucose and lipid metabolism abnormalities, increased cardiovascular risk and oxidative stressI1}. Aging is also associated with an increase in oxida... Obesity, one of the most common health problems, is associated with glucose and lipid metabolism abnormalities, increased cardiovascular risk and oxidative stressI1}. Aging is also associated with an increase in oxidative stress[2]. Considering that older adults are already at risk for oxidant stress, the additional metabolic perturbations of obesity aggravated the susceptibility to oxidant stress. Modulating age-related oxidative stress via dietary interventions could reduce free radical production and significantly improve health in aging. 展开更多
关键词 Comparative Effects of Sunflower and Olive-Linseed mixture oil Rich Diets Blood Oxidant/Antioxidant Status in overfed Aging Rats CAF PUFA
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Results of the Reduce the Pollutant Emission by Liquid Fuel Mixtures of Liquid Fuel and Sunflower Oil
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作者 Florentina Calugaru 《材料科学与工程(中英文A版)》 2012年第9期629-635,共7页
关键词 污染物排放 液体燃料 混合物 葵花籽油 化石燃料 数学模型 数据验证 NOx
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Simplex - Centroid Mixture Design Applied to theAqueous Enzymatic Extraction of Fatty Acid - BalancedOil from Mixed Seeds
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作者 Li Yang Zhang Yan +2 位作者 Wang Mei Jiang Lianzhou Sui Xiaonan 《大豆科技》 2019年第S01期1-8,共8页
A one-step method was developed to extract oil from a mixture of soybeans,peanuts,linseeds,and tea seeds using an aqueous enzymatic method.The proportion of the four seeds was targeted in accordance with a fatty acid ... A one-step method was developed to extract oil from a mixture of soybeans,peanuts,linseeds,and tea seeds using an aqueous enzymatic method.The proportion of the four seeds was targeted in accordance with a fatty acid ratio of 0.27(SFA,saturated fatty acid(s))∶1(MUFA,monounsaturated fatty acid(s))∶1(PUFA,polyunsaturated fatty acid(s)),and the oil extraction yield was maximized by applying the simplex-centroid mixture design method.Three models were developed for describing the relationship between the proportion of the individual seeds in the mixture,the fatty acid ratio in the extracted oil,and the oil extraction yield,respectively.The developed models were then analyzed using an ANOVA and were found to fit the data quite well,with R2 values of 0.98,0.93,and 0.93,respectively.The three models were validated experimentally.The results indicated that the ratio of fatty acids in the oil ranged between 0.98 and 1.12(MUFA∶PUFA)and between 0.26 and 0.28(SFA∶MUFA),which were quite close to the target values of 1 and 0.27,respectively.The oil extraction yield of 62.13%was slightly higher than the predicted value(60.32%). 展开更多
关键词 oil blend Aqueous enzymatic extraction Fatty acids mixture design Mixed seeds
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A lubrication model for bubbly oil lubrication with interfacial effect and thermal effect using the theory of multiphase mixtures
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作者 Shaohua LI Xiaohui LIN Shuyun JIANG 《Friction》 SCIE EI CAS CSCD 2024年第2期271-290,共20页
Bubbly oil lubrication is a type of lubrication method.However,the lubrication model of the bubbly oil has not been thoroughly considered.This paper aims to investigate the modelling for bubbly oil lubrication conside... Bubbly oil lubrication is a type of lubrication method.However,the lubrication model of the bubbly oil has not been thoroughly considered.This paper aims to investigate the modelling for bubbly oil lubrication considering the interfacial effect and thermal effect,and a theoretical model is established based on the theory of multiphase mixtures.The interfacial and thermal effects on the static characteristics of a thrust bearing are analyzed.A test rig for the thrust bearing is developed to measure the static characteristics of the bearing under bubbly oil lubrication.The results show that the bearing static characteristics,i.e.bearing temperature rise,film thickness,friction torque,and volume flow,increase with consideration of three interfacial effects;the bearing temperature rise increases but the film thickness,friction torque,and volume flow rate decrease with consideration of the three thermal effects;the thermal effect on the bearing static characteristics is greater than the interfacial effect. 展开更多
关键词 bubbly oil lubrication theory of multiphase mixtures interfacial effect thermal effect fluid bearing
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微波含水率检测技术在复杂油水混合形态下的应用研究
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作者 许国晨 宋宗旭 +2 位作者 张磊 孟敏 曹聪 《中外能源》 CAS 2024年第5期60-67,共8页
在油水混合物中会出现不同的乳化形态,不同的乳化形态对应的电导率和介电常数也具有显著差异,从而导致通过检测电导率和介电常数值间接测量含水率的测量结果不准确。针对复杂油水混合状态下含水率难以测准的问题,提出一种基于微波技术... 在油水混合物中会出现不同的乳化形态,不同的乳化形态对应的电导率和介电常数也具有显著差异,从而导致通过检测电导率和介电常数值间接测量含水率的测量结果不准确。针对复杂油水混合状态下含水率难以测准的问题,提出一种基于微波技术的复杂油水两相流含水率检测技术,建立了基于微波技术的“油包水”和“水包油”状态分析方法。首先通过检测微波信号穿过不同介质后信号幅值的衰减和相位的偏移,推测油水混合物的含水率值。再利用不同输入功率的微波信号在不同介电常数下功率衰减比不同的原理,来区分油水混合物的乳化状态,优化含水率的测量。室内验证和矿场试验结果表明,该系统可有效区分乳化液的混合状态,通过含水率标定值对实测数据进行修正,最终测量的含水率误差可控制在1个百分点以内,实现了复杂油水混合形态下含水率的高精度测量。 展开更多
关键词 油水混合物 含水率测量 乳化状态 微波信号 介电常数 功率衰减比
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三聚氰胺基疏水海绵的制备及其吸油性能 被引量:1
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作者 张静静 李艳香 +2 位作者 李望良 王文辰 闻明科 《石油学报(石油加工)》 EI CAS CSCD 北大核心 2024年第2期534-545,共12页
采用单宁酸(TA)/Fe^(3+)复合物(TA/Fe^(3+))对三聚氰胺海绵(MS)进行预处理,然后通过生物蜡乳液浸渍法对三聚氰胺海绵进行疏水改性,制备了高吸油倍率的疏水三聚氰胺海绵(MS-TA/Fe^(3+)-Wax)。采用扫描电子显微镜、傅里叶变换红外光谱和... 采用单宁酸(TA)/Fe^(3+)复合物(TA/Fe^(3+))对三聚氰胺海绵(MS)进行预处理,然后通过生物蜡乳液浸渍法对三聚氰胺海绵进行疏水改性,制备了高吸油倍率的疏水三聚氰胺海绵(MS-TA/Fe^(3+)-Wax)。采用扫描电子显微镜、傅里叶变换红外光谱和接触角测试等手段对三聚氰胺海绵改性前后样品进行微观形貌、结构组成和表面润湿性表征,并考察其对不同油品的吸油性能。结果表明:MS-TA/Fe^(3+)-Wax具有高度疏水性,水接触角可达141.5°;在常温常压条件下,MS-TA/Fe^(3+)-Wax对正辛烷、二氯甲烷、甲苯、柴油、泵油和菜籽油的吸油量为54.91~97.46 g/g,吸油过程符合拟二级动力学。疏水改性的三聚氰胺海绵材料通过挤压解吸附可实现循环使用,在处理油-水污染物方面具有潜在的应用前景。 展开更多
关键词 三聚氰胺海绵 疏水改性 生物蜡 油-水混合物 吸附 吸油性能 水接触角
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发电机轴承油槽密封结构对油雾泄漏的影响
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作者 刘立军 章志平 +5 位作者 胥千鑫 张送校 吴中华 孙洁 郑源 张玉全 《排灌机械工程学报》 CSCD 北大核心 2024年第5期477-483,共7页
大型水电站轴承油槽总是不可避免地发生油雾泄漏问题,改善密封结构通常是解决水电站轴承油槽甩油雾问题最简单有效的措施.为了降低油雾泄漏对发电机内部造成的污染,文中围绕某抽水蓄能电站发电机轴承油槽甩油雾问题,对油槽密封盖进行改... 大型水电站轴承油槽总是不可避免地发生油雾泄漏问题,改善密封结构通常是解决水电站轴承油槽甩油雾问题最简单有效的措施.为了降低油雾泄漏对发电机内部造成的污染,文中围绕某抽水蓄能电站发电机轴承油槽甩油雾问题,对油槽密封盖进行改型,并开展密封腔油雾多相流数值模拟研究.通过Mixture模型和SST k-ω模型解析了原密封结构和2种改进密封结构的流场分布特性,并评估了不同密封结构下的油雾泄漏情况.研究结果表明:相比于原设计模型,改进模型Ⅰ,Ⅱ的油雾泄漏量平均减少了18.9%,88.6%,改进模型Ⅱ抑制油雾效果最为显著;高压气体的注入会破坏密封腔原有的环形涡流,从而抑制油雾逸出;对于下部密封腔而言,提高进口压力,减小进口流速都有助于改善密封性能.文中的研究可为油槽密封改良以及轴承油雾泄漏控制措施提供一定的参考,提升电站的经济效益以及运行的安全稳定性. 展开更多
关键词 抽水蓄能电站 轴承油槽 油雾泄漏 密封结构优化 mixture模型
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芩蓟凉血合剂对痔病相近动物模型的影响
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作者 周蒙恩 李鹏 +2 位作者 金文琪 王若琳 郭修田 《中国实验动物学报》 CAS CSCD 北大核心 2024年第1期33-39,共7页
目的探讨芩蓟凉血合剂(Qinji Liangxue mixture,QLM)对抗痔作用的机制。方法分别使用巴豆油制剂(croton oil preparation,COP)、冰醋酸制备大鼠急性痔病动物模型,将80只SD雌性大鼠,随机分为COP组与冰醋酸组两组,每组40只。COP组,随机分... 目的探讨芩蓟凉血合剂(Qinji Liangxue mixture,QLM)对抗痔作用的机制。方法分别使用巴豆油制剂(croton oil preparation,COP)、冰醋酸制备大鼠急性痔病动物模型,将80只SD雌性大鼠,随机分为COP组与冰醋酸组两组,每组40只。COP组,随机分为对照组1(CA组),模型组1(CB组),QLM低剂量组1-1(CC组),QLM高剂量组1-2(CD组),地奥司明组1(CE组),每组8只;冰醋酸组,随机分为对照组2(GA组),模型组2(GB组),QLM低剂量组2-1(GC组),QLM高剂量组2-2(GD组),地奥司明组2(GE组),每组8只。除对照组,其余组均使用COP或冰醋酸处理,随后使用不同药物治疗7 d。使用苏木精-伊红(HE)染色观察COP及冰醋酸诱导的肛门直肠组织形态学,使用ELISA检测COP诱导的大鼠血清IL-6、TNF-α水平,记录冰醋酸诱导的大鼠肛周溃疡面积。将24只C57BL/6小鼠随机分为对照组(A组),QLM低剂量组(B组),QLM高剂量组(C组),肾上腺色腙片组(D组),每组6只,连续治疗7 d,使用毛细管法及断尾法评价QLM的止血疗效。结果QLM能够显著改善痔病相近动物模型的病理损伤,减轻COP诱导的病变程度评分(P<0.05),降低血清IL-6、TNF-α水平(P<0.05),减少冰醋酸诱导的肛周溃疡面积(P<0.05),缩短凝血及出血时间(P<0.05)。结论QLM具有良好的抗痔活性,其作用可能是通过抗炎、止血、减少组织损伤实现的。 展开更多
关键词 芩蓟凉血合剂 痔病 中医药 冰醋酸 巴豆油
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荆芥和砂仁挥发油对米象熏蒸活性的协同作用及成分研究
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作者 杨悦玲 苏懿清 +3 位作者 何洋洋 梁宗锁 王芳 梁倩 《中国粮油学报》 CAS CSCD 北大核心 2024年第3期11-18,共8页
研究20种植物挥发油对米象(Sitophilus oryzae Linnaeus)成虫的熏蒸活性以及混配的协同作用。采用水蒸气蒸馏法提取20种植物挥发油,通过气相-质谱法和化合物消除法,确定熏蒸活性和协同作用最好的2种挥发油的活性成分。结果表明:20种植... 研究20种植物挥发油对米象(Sitophilus oryzae Linnaeus)成虫的熏蒸活性以及混配的协同作用。采用水蒸气蒸馏法提取20种植物挥发油,通过气相-质谱法和化合物消除法,确定熏蒸活性和协同作用最好的2种挥发油的活性成分。结果表明:20种植物挥发油中荆芥挥发油对米象的熏蒸活性最好,LC_(50)为13.27 mg/L。砂仁挥发油表现出最大的协同作用,共毒性因子为107.14。通过化合物消除法评价荆芥挥发油和砂仁挥发油的主要活性成分分别为胡薄荷酮和(-)-4-萜品醇,对米象熏蒸活性的LC_(50)分别为7.34、8.35 mg/L,优于荆芥挥发油的熏蒸活性。胡薄荷酮和(-)-4-萜品醇按照质量比例61.13∶6.13和1∶1的比例混配,LC_(50)分别为5.91、8.29 mg/L,随着胡薄荷酮比例的增大,混剂对米象的熏蒸活性增强。研究证实了胡薄荷酮和(-)-4-萜品醇作为植物源杀虫剂具有防治米象的潜力。 展开更多
关键词 荆芥挥发油 砂仁挥发油 米象 化合物消除法 混配
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Dietary coated essential oil and organic acid mixture supplementation improves health of broilers infected with avian pathogenic Escherichia coli 被引量:4
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作者 Van Hieu Pham Waseem Abbas +6 位作者 Jinyu Huang Fangshen Guo Kaichen Zhang Linhua Kong Wenrui Zhen Yuming Guo Zhong Wang 《Animal Nutrition》 SCIE CSCD 2023年第1期245-262,共18页
Colibacillosis caused by avian pathogenic Escherichia coli(APEC)is a very prevalent disease in poultry farms in China.The exploration of effective non-antibiotic substances is of great significance for the control of ... Colibacillosis caused by avian pathogenic Escherichia coli(APEC)is a very prevalent disease in poultry farms in China.The exploration of effective non-antibiotic substances is of great significance for the control of APEC infections.This experiment evaluated the efficacy of coated essential oil and organic acid(EOA)supplementation to prevent E.coli O78 infection in broiler chickens.A total of 288 one-day-old male broiler chicks were randomly distributed into 4 groups with 6 replicates per group.Chickens were fed a diet either supplemented with EOA(500 mg/kg feed)or not,and either uninfected or infected with E.coli O78 intratracheally.Results showed that E.coli O78 infection reduced body weight gain,increased mortality and the ratio of feed to gain along with cecal and liver E.coli load,damaged gut mucosa,induced local and systemic inflammation,and altered cecal microbial composition,diversity and function(P<0.05).Supplemental EOA improved feed conversion efficiency,lowered gross lesion scores and cecal E.coli population,enhanced intestinal goblet cells and serum IgG concentration,and tended to decrease serum IL-12 production(P<0.05).Essential oil and organic acid addition downregulated IFN-γmRNA,tended to decrease mucin-2 mRNA levels while upregulating IL-10 mRNA,and tended to increase ZO-1 gene expression in the jejuna of infected birds at 7 d after E.coli O78 challenge(P<0.05).The 16S rRNA gene sequencing indicated that both EOA addition and E.coli O78 challenge altered the diversity and composition of the cecal microbiota community.Furthermore,infected birds fed EOA showed decreased Bacteroidetes and genus Lactobacillus abundance compared with the infected control.LEfSe analysis showed that Firmicutes,Ruminococcaceae,Clostridiales,Clostridia,Lactobacillus,Lactobacilaceae,and cc-115 were enriched in the non-infected but EOA-treated group(P<0.05).Collectively,dietary EOA supplementation could mildly alleviate E.coli-induced gut injury and inflammation. 展开更多
关键词 Encapsulated essential oil and organic acid mixture Avian pathogenic Escherichia coli HEALTH Broiler chicken
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100%RAP的废机油-乳化沥青冷再生沥青及混合料性能试验
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作者 黄浩 沈菊男 《建材技术与应用》 2024年第4期27-31,共5页
基于100%RAP再生率,采用废机油预润再生老化沥青,并对其进行三大指标和红外光谱试验,同时对其混合料进行干湿劈裂试验、冻融试验及马歇尔稳定度试验,以评价其力学及水稳性能。试验结果表明:废机油可以在三大指标上使老化沥青接近新沥青... 基于100%RAP再生率,采用废机油预润再生老化沥青,并对其进行三大指标和红外光谱试验,同时对其混合料进行干湿劈裂试验、冻融试验及马歇尔稳定度试验,以评价其力学及水稳性能。试验结果表明:废机油可以在三大指标上使老化沥青接近新沥青,但掺量过高会导致软化点过低,使冷再生混合料性能降低;红外光谱表明废机油具有降低亚砜基和羰基极性官能团指数的作用;经过废机油预润再生后,RAP表面老化沥青初步激活,与乳化沥青更好的粘结,可提高混合料的强度及水稳性能;废机油掺量为10%的乳化沥青再生混合料性能较差,这与废机油过量有关。 展开更多
关键词 100%RAP 废机油再生沥青 乳化沥青冷再生混合料 路用性能
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气相色谱结合化学计量在核桃油、菜籽油掺伪混合物含量判别分析中的应用
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作者 吴史博 刘延奇 +3 位作者 李超 马宁 姚恒 王萌萌 《食品与机械》 CSCD 北大核心 2024年第2期63-68,73,共7页
目的:识别核桃油中同时掺入多种其他植物油的多元掺伪。方法:采用气相色谱技术分析核桃油、菜籽油掺伪混合物中脂肪酸含量,结合化学计量方法对气相色谱数据进行建模,并对不同比例核桃油、菜籽油混合物进行判别分析。结果:主成分分析法(P... 目的:识别核桃油中同时掺入多种其他植物油的多元掺伪。方法:采用气相色谱技术分析核桃油、菜籽油掺伪混合物中脂肪酸含量,结合化学计量方法对气相色谱数据进行建模,并对不同比例核桃油、菜籽油混合物进行判别分析。结果:主成分分析法(PCA)能快速鉴别出纯核桃油和掺伪核桃油,并在一定程度上反映样本的掺伪比例;Bayes判别分析将83.33%的样品归入正确的分类;偏最小二乘判别分析法(PLS-DA)的判别准确率达87.50%;基于BP神经网络模型的判别分析,其训练集的正确率为84.21%,测试集的正确率为80.00%;基于遗传算法优化支持向量机(SVM-ga)的判别分析,其训练集和测试集的正确率均为100%。结论:多种分析模型均能不同程度地识别核桃油、菜籽油掺伪比例,其中SVM-ga模型的预测精度最佳。 展开更多
关键词 核桃油 菜籽油 掺伪混合物 气相色谱 化学计量 判别分析
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疏水SiO_(2)纤维膜的制备及其油水分离性能
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作者 孟海涛 李雪梅 +2 位作者 孟海军 李守柱 潘学聪 《棉纺织技术》 CAS 2024年第2期24-28,共5页
探讨疏水SiO_(2)纤维膜的制备及其油水分离性能。以硅酸四乙酯和甲基三甲氧基硅烷为原料,采用静电纺丝技术制备疏水SiO_(2)纤维膜并测试其油水分离性能。结果表明:SiO_(2)纤维膜的水接触角为126°,疏水性良好,可以仅在重力作用下有... 探讨疏水SiO_(2)纤维膜的制备及其油水分离性能。以硅酸四乙酯和甲基三甲氧基硅烷为原料,采用静电纺丝技术制备疏水SiO_(2)纤维膜并测试其油水分离性能。结果表明:SiO_(2)纤维膜的水接触角为126°,疏水性良好,可以仅在重力作用下有效地分离不同种类的油水混合物。对于重油‐水和轻油‐水混合物的分离通量均高于16 225 L/(m^(2)·h),分离效率大于97.9%。经过10次循环后通量损失均低于3.73%,循环稳定性好。认为:疏水SiO_(2)纤维膜在环境保护方面,特别是在含油废水的处理方面具有潜在应用。 展开更多
关键词 静电纺丝 疏水SiO_(2)纤维膜 油水分离 油水混合物 油水润湿性 耐久性
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TLA/SBR改性AC-20C沥青混合料路用性能研究
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作者 李元昊 孙黎 +3 位作者 邵景干 张鹏 李文凯 孔令绅 《粘接》 CAS 2024年第8期1-5,共5页
为改善沥青路面在运营阶段高低温及水稳定性等路用性能,选用湖沥青TLA和丁苯橡胶SBR两种改性剂对道路石油沥青及AC-20C沥青混合料进行复合改性。通过针入度、软化点、延度、布氏旋转黏度试验评价TLA、SBR不同掺配组合方案对沥青性能的... 为改善沥青路面在运营阶段高低温及水稳定性等路用性能,选用湖沥青TLA和丁苯橡胶SBR两种改性剂对道路石油沥青及AC-20C沥青混合料进行复合改性。通过针入度、软化点、延度、布氏旋转黏度试验评价TLA、SBR不同掺配组合方案对沥青性能的影响。在20%TLA+2%SBR、20%TLA+3%SBR、25%TLA+3%SBR2种改性剂优选掺配组合方案下,对沥青混合料进行相关室内试验评价。试验结果表明,TLA、SBR两种改性剂的掺入对道路石油沥青针入度、软化点、延度、布氏旋转黏度试验结果均有不同程度的影响;从高温抗车辙及抗水损害能力方面考虑,25%TLA+3%SBR+70#沥青混合料性能最优,从低温抗开裂方面考虑,20%TLA+3%SBR+70#沥青混合料性能最优。 展开更多
关键词 TLA SBR 油石比 沥青混合料 路用性能
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某型发动机引射管喷油雾故障研究
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作者 付国斌 计鑫 王振河 《机械管理开发》 2024年第4期262-264,298,共4页
针对某型发动机工作过程中引射管喷油雾故障,依据发动机滑油系统结构、工作原理、滑油系统附件工作原理,对故障进行机理分析,制定了故障树和故障排查流程.在实际工作中,应用制定的排查流程进行检查,能快速定位故障点,提高排除故障效率,... 针对某型发动机工作过程中引射管喷油雾故障,依据发动机滑油系统结构、工作原理、滑油系统附件工作原理,对故障进行机理分析,制定了故障树和故障排查流程.在实际工作中,应用制定的排查流程进行检查,能快速定位故障点,提高排除故障效率,该流程对排除同类故障具有一定的参考意义. 展开更多
关键词 发动机 滑油系统 离心通风器 空气-滑油混合液 引射管 故障树
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