oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 22 )

2018 ( 419 )

2017 ( 438 )

2016 ( 508 )

Custom range...

Search Results: 1 - 10 of 26814 matches for " 焦爱权 "
All listed articles are free for downloading (OA Articles)
Page 1 /26814
Display every page Item
基于近红外及中红外光谱融合技术快速检测黄酒中的总酚含量及其抗氧化能力
,徐学明,金征宇
- , 2016, DOI: 10.3969/j.issn.1673-1689.2016.04.004
Abstract: 为了实现对黄酒中总酚含量(TPC)及其抗氧化能力(TAC)的快速检测,探索了将傅立叶红外光谱技术应用于快速检测这两项重要指标的可行性。协同区间偏最小二乘算法(SiPLS)用于选出有效波长区间以提高模型的预测能力。支持向量机(SVM)和主成分分析(PCA)用来融合由SiPLS选出的中红外(ATR-IR)和近红外(FT-NIR)光谱的有效波段。实验结果表明基于SiPLS筛选的有效光谱变量而建立的偏最小二乘回归模型(PLS)的精度优于基于全光谱建立的经典PLS模型。基于ATR-IR建立的模型的效果略优于基于FT-NIR光谱建立的模型。此外,基于提取自ATR-IR合FT-NIR的有效区间而建立的SVM模型的预测能力要好于建立的PLS或SiPLS模型。因此,ATR-IR及FT-IR结合特征谱区筛选方法可以作为理化检测的替代手段实现对黄酒中的TAC和TPC的快速检测,同时基于两种光谱的融合技术可显著提高模型的预测精度。
In this study, Fourier-transform near infrared (FT-NIR) spectroscopy, attenuated total reflectance infrared (ATR-IR) spectroscopy and their combination for measurements of total antioxidant capacity (TAC) and total phenolic content (TPC) of Chinese rice wine (CRW) were compared. Synergy interval partial least-squares (SiPLS) algorithm was used to select wavelengths to improve PLS models and support vector machine (SVM) and principal component analysis (PCA) were applied to pre-process the merged data from two individual instruments. It was observed that models based on the efficient spectrum intervals selected by siPLS were much better than those based on the full spectra. Models from ATR-IR performed slightly better than those from FT-NIR. Moreover, SVM models based on the combination of two spectroscopies were superior to those from either FT-NIR or ATR-IR spectra, while PLS models based on the same information performed worse than those based on a single spectrum, which may be explained by some non-linearity in the data. Therefore, the integration of FT-NIR and ATR-IR was possible and could improve the prediction accuracy of TAC and TPC in Chinese rice wine
回锅肉加工及冻藏过程中风味物质的变化
贾丽娜,,赵建伟,徐学明
- , 2015, DOI: 10.3969/j.issn.1673-1689.2015.12.006
Abstract: 采用顶空固相微萃取(HS-SPME)提取回锅肉的挥发性风味成分,通过气相色谱-质谱联用法(GC-MS)对回锅肉中挥发性风味成分进行分离鉴定。GC-MS分析表明,共检测到回锅肉中91种挥发性风味物质,包括13种醛类(相对含量51.287%)、15种醇类(相对含量11.412%)、 7种含硫物质(相对含量9.397%)、12种酯类(相对含量7.736%)、6种酮类(相对含量6.983%)、18种杂环类(相对含量6.873%)、11种碳氢类(相对含量4.030%)、4种酸类(相对含量1.433%),以及5种其他挥发物(相对含量1.566%)。回锅肉经过炒制后,酯类和杂环类物质的含量和种类显著增加,对回锅肉的风味有重大贡献。通过主成分分析(PCA),第一主成分(PC1)代表了大部分(相对含量73.651%)挥发性风味物质的信息,有效地表征了回锅肉的特征风味物质。且PCA表明,不同冻藏时间的回锅肉可以被很好地区分:冻藏1个月,影响其风味的主要是1-戊烯-3-醇、异戊醇、辛醛;冻藏2~3月,影响其风味的主要是壬醛、反式-2,4-癸二烯醛、苯乙醇;冻藏5~6月,影响其风味的主要是己醛、乙醇。
Volatile flavor components from Double-fried pork was extracted by headspace solid-phase microextraction (HS-SPME) and isolated and identified by gas chromatography-mass spectrometry (GC-MS) analysis. A total of 91 volatile flavor compounds were identified,including 13 aldehydes (51.287%),15 alcohols (11.412%),7 sulphur-containing compounds (9.397%),12 esters (7.736%),6 ketones (6.983%),18 heterocyclic compounds (6.873%),11 hydrocarbons (2.264%),4 acid compounds (1.433%),and 5 others (1.566%). Esters and heterocyclic compounds significantly increased after frying and therefore had a great contribution to the special flavor of Double-fried pork. By the method of principal component analysis (PCA),the first one (PC1) mainly represented most of the information of flavor compounds among the three principal components,which was thus used as the characteristic flavor compounds. Double-fried pork of different frozen times could be clearly separated by PCA analysis, the one-month samples mainly associated with 1-penten-3-ol,3-methyl-1-butanol and octanal, the two and three-month samples mainly associated with nonanal,(E,E)-2,4-decadienal,and phenylethyl alcohol, whereas the five and six-month samples mainly associated with hexanal and ethanol
响应面法优化弹簧糊精的酶解制备工艺
闵丹丹,徐学明,,潘小卫,金征宇
- , 2018, DOI: 10.3969/j.issn.1673-1689.2018.07.005
Abstract: 以蜡质玉米淀粉为原料,通过单因素试验和响应面设计法,优化了普鲁兰酶酶解制备弹簧糊精的工艺参数,并建立数学模型,得到的最佳工艺参数为:pH 4.96、酶解温度53.32 ℃、酶用量420 U/g、酶解时间6 h,此工艺条件下制备的弹簧糊精纯度为99.2%。测定了制备的弹簧糊精的链长分布,实验结果表明聚合度(以DP表示)小于60的弹簧糊精占总弹簧糊精质量分数的95.5%,其中聚合度为DP 6~12、13~24、25~36、37~60的弹簧糊精质量分数分别为24.40%、45.08%、19.60%及10.92%。
The spring dextrin were prepared by enzymatic hydrolysis of waxy maize starch with pullulanase alone,and the process parameters were optimized by one-factor-at-a-time method and response surface methodology. The optimal results were observed at conditions of enzyme dosage 420 U/g,hydrolysis for 6 h at 53.32 ℃,pH 4.96,predicted using mathematical predictive model. Under these conditions,the spring dextrin purity was 99.2%. The chain-length distribution of the prepared spring dextrin were also evaluated. Results showed that the proportion of spring dextrin with DP<60 were 95.5%,and the relative contents of spring dextrin with DP6~12,DP13~24,DP25~36 and DP37~60 were 24.40%,45.08%,19.60% and 10.92%,respectively
傅立叶红外光谱技术快速检测黄酒中的氨基酸质量浓度
吴正宗,王芳,徐恩波,徐学明,
- , 2017, DOI: 10.3969/j.issn.1673-1689.2017.01.006
Abstract: 氨基酸含量是评价黄酒质量和风味的一项重要指标。为了实现对黄酒中氨基酸质量浓度的快速检测,作者探索了将傅立叶红外光谱技术(FT-IR)应用于黄酒中的17种自由氨基酸质量浓度的快速检测的可行性,同时采用协同区间偏最小二乘算法(SiPLS)和遗传算法(GA)选出有效波长以期提高模型的预测精度。实验结果显示与基于全波长光谱建立的经典偏最小二乘算法模型相比,基于SiPLS和GA选出来的有效光谱变量而建立的回归模型的精度有显著提高,尤其是对半胱氨酸(Cys)、精氨酸(Arg)和脯氨酸(Pro)。此外,对于所有的氨基酸,GA-SiPLS模型效果最好,交互验证相关系数均大于0.80,残余预测偏差均大于2.00。因此,FT-IR结合特征谱区筛选方法可以作为常规检测的一种替代手段实现对黄酒中的自由氨基酸的快速检测。
The content of amino acid in Chinese rice wine(CRW) is one of the most important indexes to evaluate the quality and flavor of Chinese rice wine. In order to rapidly determine the contents of free amino acids in CRW,the possibility of Fourier transform infrared spectroscopy (FT-IR) for the fast detection of 17 different kinds of free amino acids in CRW wasdiscussed. Synergy interval partial least squares(SiPLS) and genetic algorithm(GA) were used to select the most efficient spectral variables to improve the prediction precision of the classical partial least squares(PLS) model based on the full-spectrum. Compared with the PLS model based on the full-spectrum,the prediction accuracy of model based on the spectral variables selected by SiPLS and GA was significantly improved,especially for cysteine,arginine and proline. In addition,GA-SiPLS model showed the most efficient prediction accuracy to all of the free amino acids,with the correlation coefficient of cross-validation higher than 0.80 and the residual predictive deviation larger than 2.00. The FT-IR combined with efficient variable selection algorithms is confirmed as a useful method to replace the traditional methods for routine analysis of free amino acids in CRW
鸡蛋蛋黄蛋白脱磷方法的比较
王芳,,吴正宗,徐恩波,徐学明,金征宇
- , 2017, DOI: 10.3969/j.issn.1673-1689.2017.07.002
Abstract: 为保证慢性肾脏病患者蛋白营养供给充足的同时控制磷的摄入,采用一种新的脱磷方法即蛋白酶辅助碱性脱磷制备低磷蛋黄蛋白粉。同时分析比较了碱性蛋白酶辅助脱磷和碱法脱磷的效率、蛋白质溶解度、结构及氨基酸组成的差异。结果表明碱法脱磷对蛋白质氨基酸有破坏作用影响蛋白质品质;碱性蛋白酶辅助脱磷方法的脱磷率达 45.17%左右,蛋白质质量分数高达 74.74%,蛋白水解度高,脱磷效率高于碱法脱磷,表明脱磷率与水解度呈正相关;同时脱磷后蛋黄蛋白呈疏松片状结构,规则卷曲蛋白质质量分数为90%左右;碱性蛋白酶辅助脱磷的蛋黄蛋白中可溶蛋白质质量分数18.92%,溶解稳定性高达 98.62%,优于碱法脱磷。另外,采用此脱磷方法的氨基酸 FAO/WHO 模式贴近度 0.958,明显优于碱法脱磷。因此,所制备的低磷蛋白粉可作为慢性肾脏病患者的优质蛋白补充。
To supply adequate dietary protein for CKD patients while controlling phosphorus intake,low-phosphorus yolk potein was prepared by alkaline protease auxiliary dephosphorization. Meanwhile we analyzes the differences of dephosphorization efficiency,protein solubility,structure and amino acid composition between alkaline protease auxiliary dephosphorization and alkaline dephosphorization. The results showed that alkaline dephosphorization damages amino acids and affects protein quality. Dephosphorization rate and protein content of alkaline protease auxiliary dephosphorization are respectively 45.17% and 74.74%,And high protein hydrolysis shows that dephosphorization rate was positively correlated with the degree of hydrolysis;The micro structures is loose and the random coil about 90%;The soluble protein content of alkaline protease auxiliary dephosphorization yolk protein is 18.92 g/100 g,the dissolution stability was 98.62%. The FAO/WHO degree model was 0.958,which was better than the method of alkaline dephosphorization. The overall results confirmed that low-phosphorus yolk protein prepared by alkaline protease auxiliary dephosphorization can be as a high quality protein source for CKD patients
芝麻牛皮糖传统生产工艺的研究与改进

食品科学 , 1992,
Abstract: ?江苏杨州特产牛皮糖是地方传统产品。已有数百年历史,明末清初就有许多小作坊生产。它的特点是,外表满粘熟芝麻,入口香甜软糯、富有弹性、韧性,有咬劲,不粘牙。嚼如“牛皮”,颇有特色。故称谓“牛皮”糖。
八宝豆鼓加工工艺

食品科学 , 1993,
Abstract: ??<正>八宝豆豉是山东临沂的名特产品之一,迄今已有140多年的历史.由于它具有营养丰富、醇厚清香、去腻爽口、食用方便,独特的疗效等特点,有别于其它地区同类产品,赢得了广大消费者青睐.八宝豆豉是用大黑豆、茄子、鲜姜、杏仁、紫苏叶、鲜花椒、香油和白酒8种原料酿制而
红壤丘陵区农业资源开发模式研究

资源科学 , 1997,
Abstract: 红壤丘陵区具有优越的生物气候条件,以种植业为主的传统河谷农业资源开发模式,限制了丘陵山区特有农业自然资源全面与有效地开发,恶化了生态环境。因此,该地区农业的出路不能仅立足河谷耕地,应把注意力转移到占总面积70%以上的低山丘陵坡地上,实行一丘多用,立体布局,充红壤、丘陵、农业资源开发、模式
“协调型”政权:项目制运作下的乡镇政府
付伟,
社会学研究 , 2015,
Abstract: 税费改革以后,中西部基层政权从“汲取型政权”走向了“悬浮型政权”,为了维持中西部政权的正常运转和提供农村基本公共服务,一套复杂的转移支付体系开始建立。大量转移支付资金进入中西部基层社会的同时,财政资金项目化的趋势加强,导致了“项目治国”时代的来临。在项目制度下,乡镇政权的状态是:一方面资源和权力继续被上收;另一方面又不得不开始为项目进村“跑腿办事”,乡镇政权由“悬浮型政权”走向“协调型政权”。乡镇政权无钱无权,却又不得不疲于奔命,这种制度上的困境导致了项目制在基层运作过程中走向了技术治理的反面。
基岩平衡冲刷深度预报的神经网络模型
,何江
人民黄河 , 2007,
Abstract: ?采用基于拟牛顿算法快速优化修正bp神经网络算法,构建人工神经网络模型,来研究基岩平衡冲刷深度与单宽流量、上下游水位差及基岩抗冲能力等因素之间的复杂映射关系.以国内已建若干挑流工程冲刷深度的实测资料为模型的学习训练样本,对冲刷深度进行了预报,结果表明,该法具有较高的预报精度,利用此神经网络模型对冲刷深度进行预报是完全可行的.
Page 1 /26814
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.