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Monotonicity-Preserving激波捕捉格式在湍流大尺度模拟中的评估
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作者 崔健 方剑 +1 位作者 苑敬周 陆利蓬 《北京航空航天大学学报》 EI CAS CSCD 北大核心 2013年第4期488-493,共6页
对高阶激波捕捉格式的性能进行了系统的测评,重点分析了Suresh和Huynh(1997)所提出的Monotonicity-Preserving格式的性能.结果表明Monotonicity-Preserving格式的性能显著优于原始WENO(Weighted Essentially Non-Oscillatory)格式,和改... 对高阶激波捕捉格式的性能进行了系统的测评,重点分析了Suresh和Huynh(1997)所提出的Monotonicity-Preserving格式的性能.结果表明Monotonicity-Preserving格式的性能显著优于原始WENO(Weighted Essentially Non-Oscillatory)格式,和改进型WENO格式相当.对格式的分析进一步表明,迎风型的激波捕捉格式在湍流模拟方面的性能都不及高阶中心格式,其原因归结为激波捕捉格式所包含的线性和非线性耗散.因此,改进高阶激波捕捉格式的关键在于同时降低格式的线性耗散和非线性耗散,以提高格式对湍流脉动能量的保持和对小尺度脉动结构的捕捉能力. 展开更多
关键词 激波捕捉格式 湍流模拟 Monotonicity—preserving格式
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A supervised multimanifold method with locality preserving for face recognition using single sample per person 被引量:3
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作者 Nabipour Mehrasa Aghagolzadeh Ali Motameni Homayun 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第12期2853-2861,共9页
Although real-world experiences show that preparing one image per person is more convenient, most of the appearance-based face recognition methods degrade or fail to work if there is only a single sample per person(SS... Although real-world experiences show that preparing one image per person is more convenient, most of the appearance-based face recognition methods degrade or fail to work if there is only a single sample per person(SSPP). In this work, we introduce a novel supervised learning method called supervised locality preserving multimanifold(SLPMM) for face recognition with SSPP. In SLPMM, two graphs: within-manifold graph and between-manifold graph are made to represent the information inside every manifold and the information among different manifolds, respectively. SLPMM simultaneously maximizes the between-manifold scatter and minimizes the within-manifold scatter which leads to discriminant space by adopting locality preserving projection(LPP) concept. Experimental results on two widely used face databases FERET and AR face database are presented to prove the efficacy of the proposed approach. 展开更多
关键词 face recognition LOCALITY preserving MANIFOLD learning single sample PER PERSON
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Scientific Data:Preserving, Archiving and Sharing
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作者 MENG Xianxue YANG Congke 《Journal of Northeast Agricultural University(English Edition)》 CAS 2006年第2期174-177,共4页
Scientific data refers to the data or data sets generated from scientific research process through observations, experiments, calculations and analyses. These data are fundamental components for developing new knowled... Scientific data refers to the data or data sets generated from scientific research process through observations, experiments, calculations and analyses. These data are fundamental components for developing new knowledge, advancing technological progress, and creating wealth. In recent years, scientific data has been attracting more and more attention for its preserving, archiving and sharing. 展开更多
关键词 scientific data preserving archiving and sharing
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Ship recognition based on HRRP via multi-scale sparse preserving method
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作者 YANG Xueling ZHANG Gong SONG Hu 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第3期599-608,共10页
In order to extract the richer feature information of ship targets from sea clutter, and address the high dimensional data problem, a method termed as multi-scale fusion kernel sparse preserving projection(MSFKSPP) ba... In order to extract the richer feature information of ship targets from sea clutter, and address the high dimensional data problem, a method termed as multi-scale fusion kernel sparse preserving projection(MSFKSPP) based on the maximum margin criterion(MMC) is proposed for recognizing the class of ship targets utilizing the high-resolution range profile(HRRP). Multi-scale fusion is introduced to capture the local and detailed information in small-scale features, and the global and contour information in large-scale features, offering help to extract the edge information from sea clutter and further improving the target recognition accuracy. The proposed method can maximally preserve the multi-scale fusion sparse of data and maximize the class separability in the reduced dimensionality by reproducing kernel Hilbert space. Experimental results on the measured radar data show that the proposed method can effectively extract the features of ship target from sea clutter, further reduce the feature dimensionality, and improve target recognition performance. 展开更多
关键词 ship target recognition high-resolution range profile(HRRP) multi-scale fusion kernel sparse preserving projection(MSFKSPP) feature extraction dimensionality reduction
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(G^2-continuous) SHAPE PRESERVING CUBIC INTERPOLATION SPLINE CURVE
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作者 Fang Kui(Department of System Engineering and Mathematics, NUDT, Changsha,410073) 《国防科技大学学报》 EI CAS CSCD 北大核心 1995年第3期65-69,共5页
(G~2-continuous)SHAPEPRESERVINGCUBICINTERPOLATIONSPLINE CURVEFangKui(DepartmentofSystemEngineeringandMathema... (G~2-continuous)SHAPEPRESERVINGCUBICINTERPOLATIONSPLINE CURVEFangKui(DepartmentofSystemEngineeringandMathematics,NUDT,Changsh?.. 展开更多
关键词 G^2-连续 插值 样条曲线
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Preparation of Biodegradable Polylactic Acid/Ethyl Cellulose/Zein Composite Film and Its Effect on the Preservation of Chilled Fresh Meat
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作者 ZHOU Ling YU Ya +8 位作者 YUAN Mengting WU Dongxu CHEN Ya LIU Yanan SU Jingjing CHEN Sihan WANG Juhua SHENG Bulei XUE Xiuheng 《食品科学》 北大核心 2025年第15期324-337,共14页
In this study,composite films consisting of polylactic acid(PLA),ethyl cellulose(EC),and zein were prepared by solution casting method,and their performance and application in chilled fresh meat preservation were inve... In this study,composite films consisting of polylactic acid(PLA),ethyl cellulose(EC),and zein were prepared by solution casting method,and their performance and application in chilled fresh meat preservation were investigated.The results showed that the three materials had satisfactory compatibility in the composite film.Addition of EC and zein effectively improved the mechanical properties,thermodynamic properties,surface hydrophilicity,oxygen permeability,and degradation properties of PLA films.When the ratio of PLA to EC was 3:7,the tensile strength and elongation at break reached maximum values of 16.6 MPa and 30.5%,respectively.Moreover,under different conditions,the composite film exhibited better degradability than the PLA film.The composite film with a 3:7 ratio of PLA to EC had the best performance,with a degradation rate of 21.75%after 84 days.Chilled fresh meat wrapped with the composite film showed significantly improved antioxidant,antibacterial,and water-holding properties. 展开更多
关键词 biodegradable film polylactic acid ethyl cellulose ZEIN chilled fresh meat preservATION
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On Inheriting and Preserving the Cultural Heritage of Nuo in Jiangxi Province
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作者 Xie Qingzhi 《学术界》 CSSCI 北大核心 2013年第7期299-304,共6页
There is a great necessity to inherit and preserve the cultural heritage of Nuo in Jiangxi Province for its artistic value,economic value and social value.In reality,however,the disappearance of culture-inheriting car... There is a great necessity to inherit and preserve the cultural heritage of Nuo in Jiangxi Province for its artistic value,economic value and social value.In reality,however,the disappearance of culture-inheriting carriers and the failure to protect relevant resources all conspire against the task of inheriting and preserving this unique inheritance.Government needs to put its weight behind this work by establishing institutions and providing funds to restore the culture of Nuo in Jiangxi. 展开更多
关键词 文化遗产 江西省 保护 传承 艺术价值 社会价值 经济价值 承载体
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射血分数保留的心力衰竭药物治疗进展
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作者 王艺衡 许晓明 +5 位作者 夏云龙 夏林莺 韩雪 郭永珍 刘泉池 闫文俊 《中国全科医学》 北大核心 2026年第3期403-408,共6页
射血分数保留的心力衰竭(HFpEF)是一种病理生理机制复杂的系统性疾病,占所有心力衰竭类型50%以上,5年死亡率高达50%~75%,危害极大。HFpEF具有极强的异质性,病因、病理生理机制及临床表现多样,治疗困难。尽管如此,近年来HFpEF治疗仍取得... 射血分数保留的心力衰竭(HFpEF)是一种病理生理机制复杂的系统性疾病,占所有心力衰竭类型50%以上,5年死亡率高达50%~75%,危害极大。HFpEF具有极强的异质性,病因、病理生理机制及临床表现多样,治疗困难。尽管如此,近年来HFpEF治疗仍取得了很大的进步,部分药物已被证实可改善HFpEF患者生活质量,减少不良事件的发生。本文基于HFpEF独特的病理生理机制,对HFpEF相关药物治疗的最新临床证据进行综述,旨在为HFpEF的综合治疗提供理论基础和实践指导。 展开更多
关键词 心力衰竭 射血分数保留的心力衰竭 异质性 药物治疗 综述
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Effects of caprock sealing capacities on coalbed methane preservation:Experimental investigation and case study 被引量:3
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作者 TIAN Fu-chao LIANG Yun-tao +1 位作者 WANG De-ming JIN Kan 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第4期925-937,共13页
Caprocks play an important role in the trapping of coalbed methane(CBM)reservoirs.To study the sealing capacities of caprocks,five samples with different lithologies of Neogene clayrock,Paleogene redbeds,Permian sands... Caprocks play an important role in the trapping of coalbed methane(CBM)reservoirs.To study the sealing capacities of caprocks,five samples with different lithologies of Neogene clayrock,Paleogene redbeds,Permian sandstone,Permian mudstone and Permian siltstone were collected and tested using experimental methods of microstructure observation,pore structure measurement and diffusion properties determination.Results indicate that with denser structures,lower porosities,much more developed micropores/transition pores and higher pore/throat ratios,mudstone and siltstone have the more ideal sealing capacities for CBM preservation when comparing to other kinds of caprocks;the methane diffusion coefficients of mudstone/siltstone are about 6 times higher than sandstone and almost 90 times higher than clayrock/redbeds.To further estimate the CBM escape through caprocks,a one-dimensional CBM diffusion model is derived.Modeling calculation result demonstrates that under the same thickness,the CBM sealing abilities of mudstone/siltstone are almost 100 times higher than those of clayrock/redbeds,and nearly 17 times higher than sandstone,which indicates that the coal seam below caprocks like clayrock,redbeds or sandstone may suffer stronger CBM diffusion effect than that below mudstone or siltstone.Such conclusion is verified by the case study from III3 District,Xutuan Colliery,where the coal seam capped by Paleogene redbeds has a much lower CBM content than that capped by the Permian strata like mudstone,siltstone and sandstone. 展开更多
关键词 CAPROCK sealing capacity coalbed methane preservATION
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Biomechanical Manifestations of Diastolic and Systolic Function in Rats with Heart Failure with Preserved Ejection Fraction 被引量:1
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作者 Zhongjie Yin Wenchang Tan 《医用生物力学》 EI CAS CSCD 北大核心 2019年第A01期77-77,共1页
Objective Heart failure(HF)is divided into two types:Heart failure with reduced ejection fraction(HFrEF)and heart failure with preserved ejection fraction(HFpEF).The latter always results in diastolic dysfunction,char... Objective Heart failure(HF)is divided into two types:Heart failure with reduced ejection fraction(HFrEF)and heart failure with preserved ejection fraction(HFpEF).The latter always results in diastolic dysfunction,characterized by changes in mechanical properties.The objective of this study is to build a finite element(FE)model of HFpEF and analyze diastolic and systolic function in rats.Methods Ten Dahl salt-sensitive rats were fed either a low-salt(LS)(n=5)or highsalt(HS)(n=5)diet beginning at 7 weeks of age and scanned by ultrasonic machine at 14 weeks of age.A non-linear FE model of the left ventricle(LV)was built from cardiac echo images at end-diastole and passive material properties of the LV were prescribed using Fung’s transversely isotropic constitutive law.Fiber angles of the endocardium and epicardium were prescribed as 53°°and-52°,respectively,with respect to the circumferential direction and varied linearly through the LV wall.The method developed by Krishnamurthywas used to determine the unloaded geometry to estimate the Fung passive material parameters.LV end-diastolic pressure(EDP)was determined from the measured pressure waves and applied to the endocardium at the unloaded geometry to simulate passive filling.Active material properties of the LV were prescribed using Guccione’s time-varying elastance model and maximum isometric tension was scaled to match the measured peak systolic pressure.The finite element model was then coupled to the Windkessel model,whose parameters were adjusted to the measured hemodynamics.Results Measured LVEDPs of LS and HS rats were 4.9±3.4 mmHg and 13.2±5.4 mmHg(P-0.030 8),respectively.End-diastolic Cauchy stress along the fiber direction for LS rats was significantly lower than for HS rats(0.91±0.60 kPa vs 3.00±0.63 kPa,P=0.001 4)and there was a similar trend in end-diastolic Green Strain along the fiber direction(0.058±0.003 vs 0.072±0.010,P=0.012 8,Figure 1b),as well.There was no distinctive difference between end-systolic Cauchy stress along the fiber direction for LS rats and HS rats(17.2±4.3 kPa vs 17.2±5.5 kPa,P=0.991 9)but end-systolic Green Strain along the fiber direction for LS rats was significantly higher than for HS rats(-0. 108±0.017 vs-0.065±0.024,negative sign represents direction).Conclusions For rats with HFpEF,it is the elevated LVEDP that induces the increase in end-diastolic stress and strain,thereby leading to diastolic dysfunction.Because of the preserved ejection fraction,HFpEF has less effect on systolic function. 展开更多
关键词 BIOMECHANICAL MANIFESTATIONS Heart Failure preservED EJECTION Fraction CAUCHY
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Inhibition Effect of Herbal Preservatives on Listeria monocytogenes on Chilled Pork
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作者 LIU Liu KONG Baohua +1 位作者 DIAO Xinping LIU Jing 《Journal of Northeast Agricultural University(English Edition)》 CAS 2008年第3期36-43,共8页
This study investigated the growth situation of Listeria monocytogenes on chilled pork and the effect of herbal preservatives on this pathogen. The inhibitions of herbal preservatives were identified. The minimum inhi... This study investigated the growth situation of Listeria monocytogenes on chilled pork and the effect of herbal preservatives on this pathogen. The inhibitions of herbal preservatives were identified. The minimum inhibitory concentrations (MIC) of cinnamon and clove were all 0.79 mg.mL^-1, while the rosemary was 1.58 mg.mL^-1. And the composite herbal preservatives were got through orthogonal experiment. The optimum proportion was as following on agar medium: 1.16 mg.mL^-1 cinnamon+2.38 mg. mL^-1 rosemary+3.17 mg. mLl clove (herb combination number 5), while on chilled pork, the strong inhibition of L. monocytogenes was showed, which demonstrated that the surface application of herb combination resulted in an effective delay of L. monocytogenes growth. 展开更多
关键词 Listeria monocytogenes chilled pork HERB preservATIVES
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Application of Hyperspectral Imaging Technology in Rapid Detection of Preservative in Milk
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作者 Sun Hong-min Huang Yu +1 位作者 Wang Yan Lu Yao 《Journal of Northeast Agricultural University(English Edition)》 CAS 2020年第4期88-96,共9页
To ensure the quality and safety of pure milk,detection method of typical preservative-potassium sorbate in milk was researched in this paper.Hyperspectral imaging technology was applied to realize rapid detection.Inf... To ensure the quality and safety of pure milk,detection method of typical preservative-potassium sorbate in milk was researched in this paper.Hyperspectral imaging technology was applied to realize rapid detection.Influence factors for hyperspectral data collection for milk samples were firstly researched,including height of sample,bottom color and sample filled up container or not.Pretreatment methods and variable selection algorithms were applied into original spectral data.Rapid detection models were built based on support vector machine method(SVM).Finally,standard normalized variable(SNV)-competitive adaptive reweighted sampling(CARS)and SVM model was chosen in this paper.The accuracies of calibration set and testing set were 0.97 and 0.97,respectively.Kappa coefficient of the model was 0.93.It could be seen that hyperspectral imaging technology could be used to detect for potassium sorbate in milk.Meanwhile,it also provided methodological supports for the rapid detection of other preservatives in milk. 展开更多
关键词 hyperspectral imaging technology preservATIVE MILK potassium sorbate competitive adaptive reweighted sampling(CARS)
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In Vitro Slow Growth Preservation of Vaccinium uliginosum
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作者 Dai Zhiguo Zhang Youlai +4 位作者 Yang Lie Li Hongmei Li Zheng Gao Qingyu Zhang Bingxiu 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第4期31-45,共15页
As an important wild blueberry resource,Vaccinium uliginosum has attracted more and more attention.At present,the wild resources are under destruction.The conservation of wild Vaccinium uliginosum resources is imminen... As an important wild blueberry resource,Vaccinium uliginosum has attracted more and more attention.At present,the wild resources are under destruction.The conservation of wild Vaccinium uliginosum resources is imminent.However,there are few researches on the protection and preservation of its germplasm resources.In vitro preservation is an important method for germplasm conservation.In this study,one strain of wild Vaccinium uliginosum was used as material.The effects of temperature(25℃,15℃,10℃,or 0℃),media(WPM,1/2WPM or 1/3WPM),medium supplements(sorbitol or mannose),and photoperiod(8,10,12,or 14 h•d^(-1))on the growth,survival rate and rejuvenation rate of the plantlets were studied.The physiological changes of plantlets during preservation were analyzed.Methylation-sensitive amplified polymorphism(MSAP)analysis of genomic DNA methylation of plantlets was carried out to explore the genetic stability of the plantlets after preservation.The research results provided a theoretical basis for the germplasm preservation of Vaccinium uliginosum. 展开更多
关键词 Vaccinium uliginosum L. slow growth in vitro preservation methylation-sensitive amplified polymorphism
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Can glucose preservatives be avoided in blood samples?
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作者 Prabin Gyawali Madhurima Mukherjee +2 位作者 Rajesh Kumar Thakur Krishnananda Prabhu Anjali Rao 《海南医学院学报》 CAS 2009年第12期1520-1523,共4页
Objective:To evaluate the effect of cooling of whole blood samples without an anticoagulant and glucose preservative on glucose and other commonly measured clinical analytes by serial measurements over a three hour pe... Objective:To evaluate the effect of cooling of whole blood samples without an anticoagulant and glucose preservative on glucose and other commonly measured clinical analytes by serial measurements over a three hour period. Methods: Thirty healthy adult volunteers about 20-50 years old,from Kasturba Medical College,Manipal (2008) were the participants. After obtaining informed consent from each participant,blood was collected (2 mL each) in three vacutainers-one without the use of an anticoagulant and glucose preservative,one with sodium fluoride-potassium oxalate and the other with disodium ethylene diamine tetraacetic (EDTA). Automatic analyzer Hitachi was used to measure glucose and other common clinical laboratory analytes,every hour for three hours. Results: The refrigerated samples without an anticoagulant and preservative,showed slightly lower values of glucose as compared to fluorinated samples but difference between these groups was not statistically significant (P value> 0.05).Also cooling had no effect on other analytes except potassium.Conclusion: Fluoride preservative as a regular practice for glucose samples can be avoided if the samples can be processed quickly as fluoriated samples also show a marginal fall in glucose values. 展开更多
关键词 抗凝血剂 葡萄糖防腐剂 临床 医学
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数智技术在文物预防性保护中的应用现状及前景 被引量:5
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作者 孙满利 邓凯 +4 位作者 沈云霞 孙骞 毛维佳 赵凤燕 吴晨 《西北大学学报(自然科学版)》 北大核心 2025年第1期23-35,共13页
文物预防性保护是文物保护中至关重要的一环,经过文物保护工作者的不懈努力,我国文物预防性保护在理论研究和实践应用方面均取得显著成就。通过对国内外文献进行整理和分析,认为我国现阶段文物预防性保护仍然存在风险监测与识别不足、... 文物预防性保护是文物保护中至关重要的一环,经过文物保护工作者的不懈努力,我国文物预防性保护在理论研究和实践应用方面均取得显著成就。通过对国内外文献进行整理和分析,认为我国现阶段文物预防性保护仍然存在风险监测与识别不足、风险分析与评估不全面、风险控制比较单一、文物价值阐释深度和广度不足、利用传承方式不丰富、创新速度缓慢等主要问题。数字化技术在各领域都展现出了强大的优势,已应用于文物预防性保护,为文物预防性保护的持续推进开辟了新的方向。数智技术作为数字化技术发展的新阶段,具有数据驱动、高度智能化、实时性与高效性、融合性与协同性、普适性与个性化、动态优化与自我迭代等特征,可以为文物预防性保护提供有力支撑。分析认为,数智技术在文物预防性保护的数字化采集与建模、环境监测与预警、数据挖掘与分析、虚拟现实展示与应用、数字化管理等方面已有良好基础,将数智技术的快速发展与文物预防性保护的阶段需求进一步相结合,在数据采集、数据挖掘、风险识别、风险预报、风险管控、虚拟修复、数字建档、虚拟展示等应用中构建数字时代文物预防性保护科学体系,运用数智技术深化文物预防性保护的实践,是解决当前保护难题的关键途径,也是推动文物预防性保护领域新质生产力形成、突破现有瓶颈的重要策略。 展开更多
关键词 文物保护 预防性保护 数智技术
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茴香醛微胶囊的制备、表征及其在胡萝卜保鲜中的应用 被引量:1
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作者 王婷 龙海涛 +3 位作者 李永才 李丽 王希望 毕阳 《食品科学》 北大核心 2025年第14期282-290,共9页
为开发植物精油微胶囊并研究其在果蔬保鲜中的应用情况,以茴香醛为芯材,辛烯基琥珀酸酐淀粉和壳聚糖为壁材,采用喷雾干燥法制备茴香醛微胶囊,并研究其对胡萝卜的保鲜效果。结果表明,茴香醛能被辛烯基琥珀酸酐淀粉和壳聚糖成功包埋,当添... 为开发植物精油微胶囊并研究其在果蔬保鲜中的应用情况,以茴香醛为芯材,辛烯基琥珀酸酐淀粉和壳聚糖为壁材,采用喷雾干燥法制备茴香醛微胶囊,并研究其对胡萝卜的保鲜效果。结果表明,茴香醛能被辛烯基琥珀酸酐淀粉和壳聚糖成功包埋,当添加量为3.5 g时,乳液分散性好,包埋率达77.21%,形成的微胶囊呈球形,表面光滑,且包埋后茴香醛热稳定性得到提高。进一步研究表明茴香醛微胶囊熏蒸处理能有效降低胡萝卜贮藏期间的呼吸强度,有效延缓胡萝卜采后L^(*)值的上升和a^(*)、b^(*)值的下降,以及可溶性固形物含量的下降和质量损失率的上升,维持胡萝卜的硬度等质构特性,同时微胶囊熏蒸处理还提高了胡萝卜组织的过氧化物酶、超氧化物歧化酶和过氧化氢酶活性。综上,制备的茴香醛微胶囊熏蒸处理可有效维持胡萝卜的采后品质。 展开更多
关键词 胡萝卜 保鲜 茴香醛 微胶囊 抗氧化
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Reflections on the Ecological Situations and Preservation of Tujia Language As An Endangered Language
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作者 Chen Chihua 《学术界》 CSSCI 北大核心 2016年第8期281-286,共6页
Tujia Language is an endangered language.Language endangerment is deteriorating under the background of globalization.The preservation of endangered languages is more urgent and important than before.The best preserva... Tujia Language is an endangered language.Language endangerment is deteriorating under the background of globalization.The preservation of endangered languages is more urgent and important than before.The best preservation of the endangered languages is to study them.The language ecology and preservation problem of Tujia Language will be investigated and discussed in this paper. 展开更多
关键词 生态保护 语言 濒危 生态现状 全球化
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明胶-纳米粒子复合膜的制备及其对水产品的保鲜作用 被引量:1
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作者 王成 纪倩倩 +6 位作者 江宁 岳泽峰 张强 孙荣雪 刘钱媛 李志强 王兴娜 《江苏农业学报》 北大核心 2025年第5期1009-1020,共12页
本研究将负载DL-3-苯乳酸的壳聚糖纳米粒子(NP)添加至明胶(GE)基体中,制成明胶-纳米粒子复合膜(GE-NP),并探究不同壳聚糖纳米粒子添加量(0、2%、4%、6%、8%、10%)对复合膜性能的影响。结果表明,综合考虑力学性能、紫外线阻隔性能、氧气... 本研究将负载DL-3-苯乳酸的壳聚糖纳米粒子(NP)添加至明胶(GE)基体中,制成明胶-纳米粒子复合膜(GE-NP),并探究不同壳聚糖纳米粒子添加量(0、2%、4%、6%、8%、10%)对复合膜性能的影响。结果表明,综合考虑力学性能、紫外线阻隔性能、氧气阻隔性能、水蒸气阻隔性能和抑菌性能,明胶-8%纳米粒子复合膜(GE-NP_(8%))的性能最佳。通过低场核磁共振和变场核磁共振分析发现,纳米粒子与明胶分子之间的相互作用增强了GE-NP_(8%)复合膜的交联强度,减小了自由体积,使其结构更加致密。鱼肉保鲜试验中,贮藏第10 d,GE-NP_(8%)处理鱼肉红绿值(a^(*))和黄蓝值(b^(*))与新鲜鱼肉的差异较小。贮藏第10 d,与聚乙烯膜处理、明胶膜处理相比,GE-NP_(8%)处理鱼肉pH值、挥发性盐基氮含量(TVB-N)、硫代巴比妥酸含量(TBA)、菌落总数(TVC)上升幅度较小,同时鱼肉硬度、弹性、胶黏性、咀嚼性等质构参数下降幅度较小。综上,GE-NP_(8%)复合膜可有效减缓鱼肉的品质劣变,延长其货架期。本研究结果可为延长水产品保质期及保持其品质提供理论依据和技术支持。 展开更多
关键词 壳聚糖纳米粒子 明胶 保鲜膜 阻隔性能 抑菌性能
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原木端压灌注乙醇对木材干燥、脱脂及染色的影响 被引量:1
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作者 解卫海 仝伯强 +2 位作者 刘丹 张萍 朱建军 《东北林业大学学报》 北大核心 2025年第3期119-124,共6页
以黑松(Pinus thunbergii Parl.)生材为材料,探索原木端压灌注乙醇对木材进行干燥、脱脂、染色的作用。使用无水乙醇(表面张力不到水的表面张力的1/3)替换木材中的水溶液,用乙醇的挥发代替木材内部原有的水分蒸发,进行木材干燥以减少木... 以黑松(Pinus thunbergii Parl.)生材为材料,探索原木端压灌注乙醇对木材进行干燥、脱脂、染色的作用。使用无水乙醇(表面张力不到水的表面张力的1/3)替换木材中的水溶液,用乙醇的挥发代替木材内部原有的水分蒸发,进行木材干燥以减少木材的干燥缺陷,以及用乙醇冲洗出树脂道中的树脂,对木材进行脱脂,同时观察加有亮蓝指示剂的乙醇在木材内部的染色情况。试验结果表明:在0.2~0.3 MPa压力下,灌注乙醇1.0~1.5 h,消耗相当于原木中总含水量体积3倍的乙醇,能够置换出原木总含水量中77.0%的水分,其松香的脱除率为70.8%。增加乙醇的压注量和压注时间能够使木材排出更多水分和松脂。在最初收集的2002 mL木材压出液中(相当于木材总含水量的38%)不含有乙醇,其后收集的木材压出液中乙醇比例逐步升高,水的比例逐步降低。当压出液中含有体积分数为11%的乙醇时,木材压出液的电导率下降一倍;当压出液中乙醇的体积分数超过74%或更高时,压出液的电导率反而有所上升。压注乙醇的木块气干速度为对照的2.82倍。对照黑松木试样板在(103±2)℃烘干后,普遍存在内裂,乙醇灌注后的弦切板在(103±2)℃烘干后没有观察到内裂。 展开更多
关键词 乙醇灌注 木材干燥 木材脱脂 木材染色 木材防腐
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抗菌肽的抑菌机制及其在食品防腐保鲜中的应用 被引量:2
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作者 李玉珍 肖怀秋 +3 位作者 王斌 廖琼 刘畅宇 曹慧君 《食品科学》 北大核心 2025年第15期415-425,共11页
由于食品富含蛋白质、脂肪和碳水化合物,在生产、加工和储运等环节极易受到致病微生物或腐败微生物污染,从而产生生物毒素或造成食品腐败损失。研究表明,抗菌肽对致病微生物或腐败微生物具有较好的抑菌活性,且部分抗菌肽兼具抗氧化、清... 由于食品富含蛋白质、脂肪和碳水化合物,在生产、加工和储运等环节极易受到致病微生物或腐败微生物污染,从而产生生物毒素或造成食品腐败损失。研究表明,抗菌肽对致病微生物或腐败微生物具有较好的抑菌活性,且部分抗菌肽兼具抗氧化、清除自由基等活性,可通过抑菌和抗氧化协同作用增强其对食品的抗菌保鲜作用。抗菌肽作为一种新型生物抗菌保鲜剂,在食品抗菌保鲜领域具有很好的应用前景。本文首先从细胞质膜损伤和非细胞质膜损伤视角系统阐明抗菌肽的抑菌分子机理;随后,对抗菌肽在各类食品抗菌保鲜中的应用研究进行详尽综述;最后,对抗菌肽作为一种新型抗菌保鲜剂,在食品抗菌保鲜中应用存在的问题进行系统剖析,并提出针对性的发展对策,以期为抗菌肽在食品抗菌保鲜中的应用提供理论与实践参考。 展开更多
关键词 抗菌肽 抑菌机制 膜损伤机理 非膜损伤机理 食品保鲜
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