食用槟榔热风干燥特性及动力学模型

本文采用Fick第二扩散定律与槟榔干燥的数学模型研究了食用槟榔在不同干燥温度下的热风干燥特性、水分有效扩散系数、表观活化能等参数与干燥动力学方程之间的相互关系。结果表明:槟榔在70℃与75℃的干燥曲线有显著性差异(p0.05),槟榔热风干燥是内部水分扩散控制的降速干燥过程;槟榔水分扩散系数变化范围:青果Deff=6.45×10~(-9)~1.17×10~(-8) m~2/s,烟果Deff=7.47×10~(-9)~1.21×10~(-8) m~2/s;干燥表观活化能:青果Ea=30.32 kJ/mol,烟果Ea=23.38 kJ/mol。单项扩散模型与Page模型的常数项系数受温度影响显著(p0.05);单项扩散干燥模型为描述食用槟榔的最佳数学模型(青果:R2avg=0.97,RMSEavg=0.023;烟果:R2avg=0.98,RMSEavg=0.025);65℃~85℃热风干燥条件下的干燥模型可表述为:MR青果=(2×10~(-4)T2-0.037T+2.54)exp-(3×10~(-5)T3-0.0064T2+0.51T-13.06)t;MR烟果=(3×10~(-4)T2-0.062T+3.67)exp-(-4×10~(-4)T2+0.061T-2.027)t,可为其干燥工艺的控制提供技术依据。     

紫外双波长-pH转换法同时测定混合物中的丙酮酸和乳酸

建立了一种同时测试混合物中乳酸与丙酮酸含量的紫外分光光度方法。在碱性环境下,利用双波长法,测定混合物中的丙酮酸,线性回归方程C=6.75×10-3+0.626A,线性范围为0.0505~0.505μg/mL;在酸性条件下,利用直接分光光度法,测定混合物中的乳酸,线性回归方程C=1.547+51.76A,线性范围为1.22~244μg/mL。采用本法测量工业样品,其结果与液相色谱法得到的数据基本吻合,但本法实验步骤更加简单、操作更加方便,且容易实现工艺过程的在线检测。     

复合多糖胶囊中原花青素含量测定方法的研究

对复合多糖胶囊中功效成分原花青素含量测定方法进行方法学验证.按照《中国药典》2010版第一部附录ⅩⅤⅢ《中药标准分析方法验证指导原则》中的相关规定进行验证.该方法在待测液中原花青素含量在0～200 μg/mL范围内线性相关,回归方程:A=0.0037X+ 0.0078,R2=0.9997;重复性试验RSD值小于2.5％...     

共振散射光谱法测定牛奶中的四环素

在1.0×10~(-5) mol/L的盐酸溶液中,四环素可与Co~(2+)发生络合反应形成螯合阳离子,该阳离子再与带负电的铝试剂通过静电引力作用形成三元离子缔合物,从而使反应体系的共振散射强度显著增强。在最优条件下,体系的共振散射强度增加值(△I)与四环素浓度在2.0×10~(-7 )mol/L～1.5×10~(-5) mol/L范围内呈良好的线性关系,回归方程为△I=1.247×10~7c+16.44(c为Tc的浓度,mol/L),检出限为4.81×10~(-8) mol/L,相关系数为0.997 1,据此建立一种测定四环素的新方法。将该方法用于检测牛奶样品中的四环素,加标回收率在99.28%～101.70%之间。     

大蒜片真空微波干燥模型的建立

为探索出不同真空微波条件对大蒜片干燥速率的影响,选取微波功率Q、负载量m、真空度Pw等因素,范围分别在50～150W、80～140 g、0.07～0.09MPa,以干燥速率为指标在切片厚度3 mm条件下进行试验.试验结果表明:大蒜片的真空微波干燥符合薄层干燥模型,可用Page模型描述本试验干燥过程,通过SPSS分析得出Page模型参数k、n值与微波功率Q、负载量m、真空度Pw之间的回归方程:k=-0.03+3.4× 10-4Q-3.205×10-4m+0.6Pw、n=1.467-1.61×10-3Q+3.63×10-3m-7.2Pw,得出Page模型表达式.     

同步荧光光谱法测定滁菊总黄酮含量

为快速测定滁菊总黄酮含量,根据黄酮类化合物与Al3+形成荧光络合物原理,以芦丁为标样,发射波长和激发波长的差值Δλ为40nm,狭缝均为10nm,测定437nm处的同步荧光强度。结果表明,该方法的检出限为1.6×10-8g/mL,线性范围在0~4.28×10-6g/mL之间,线性回归方程:y=26.6868x+17.7878,相关系数R2为0.9904,平均回收率96.5%~100.7%,相对标准偏差为0.732%。本法操作简便、快速,能够准确测定滁菊总黄酮含量。     

关于“K.Y.B”——了解自己的身体

“K.Y.B”原文是 know your Body即了解自己的身体,现在许多国家正在流行这一运动,我们根据日本的材料,加以介绍如下:动脉硬化、高血压、脑溢血、心肌梗塞和糖尿病等成年人的疾病,都被称无征候的疾病,到发病时为止,潜伏很深。追溯其病源,在儿童时期,就能检查出来。发病的原因是:高、低胆固醇不平衡,高血压、肥胖病和吸烟等不利因素,互相影响,互相促进,有所发展而成。最近,儿童和青少年患有成年人疾病的人数增加,已成为社会上的大问题,因此,     

预防动脉硬化要合理膳食

动脉硬化是多种中老年疾病的病理基础,它的发病与年龄、性别、血脂、血压以及饮食习惯等多种因素有关。 实践证明,合理膳食是预防动脉硬化的关键之一,它包括以下几方面内容:     

小麦粉品质指标与面包感官品质的相关性分析

选择11个不同品种的小麦粉进行品质特性测定,用实验室方法制作吐司面包并进行质量评价。通过对小麦粉品质特性与吐司面包感官评分间的相关性分析,及对小麦粉品质特性与吐司面包总评分的回归分析,得出小麦粉的湿面筋、稳定时间、弱化度、拉伸面积、延伸度、最大拉伸阻力均对吐司面包的总评分有显著影响,吐司面包总评分与这些品质指标间的回归方程为:吐司面包总评分=-248.26+6.389×湿面筋+0.755×稳定时间+1.243×弱化度-0.283×拉伸面积+0.236×延伸度+0.078×最大拉伸阻力,面包总评分与方程预测得分间的相关系数达到0.962 4,呈极显著正相关。     

快速预测粉质拉伸指标方法的探究

为了满足小麦加工企业对优质小麦收购快速检测的需要,从江苏省采集了71份品种为郑麦9023的样品,进行小麦常规指标和内在品质指标的检测,通过对检测数据做2个变量相关分析和多元线性回归分析,探究粉质拉伸指标中的稳定时间、拉伸面积的快速预测方法.结果表明,体积质量(x1)、面筋指数(x2)、湿面筋含量(x3)、硬度指数(x4)与稳定时间(y1)、拉伸面积(y2)显著正相关;稳定时间的多元线性回归方程:y1=0.156×x1+0.051×x2 +0.674×x3-134.253;拉伸面积的多元线性回归方程为:y2=0.824×x1+1.587×x4+2.212×x3-700.947.     

新品种粤糖03-373蔗产量影响因素的多元回归分析

对早熟高糖新品种粤糖03-373产量及构成因子进行了相关、多元回归和通径分析。相关分析结果表明,蔗茎产量与有效茎数、茎长和茎径都呈极显著相关,与有效茎数关系最为密切;多元回归分析和通径分析结果表明,有效茎数对蔗茎产量的贡献最大,其次是茎长,茎径最小。3个因素对蔗茎产量的多元回归方程为y=-2.8713+1.5497x1+5.8990x2-395.4294x3(R=0.9672**)。有效茎数和茎长是粤糖03-373获得高产的主要因素和重要因素,该品种属于茎数型品种,栽培上应发挥其茎数优势,兼顾茎长(株高),达到增产目的。     

不同温度下充氮低氧对赤拟谷盗各虫态致死效果与时间研究

了解低温对充氮低氧气调致死害虫过程和时间的影响程度,以及氮气气调过程中害虫异常行为反应与种群完全致死时间的关系可为低温充氮(低氧)与成功杀虫应用提供指导。分别在低温18℃、准低温23℃和常温28℃条件下,测定了赤拟谷盗的卵、幼虫、蛹、成虫各个虫态在控制氮气体积分数98%(氧气2%以下)过程中不同时间的死亡率及完全致死时间,以及视频监测下成虫行动异常和击倒反应率与种群完全致死的关系。98%氮气体积分数下,18、23、28℃时赤拟谷盗卵的死亡率-时间回归方程分别为y=3.61+5.47、y=3.92x+11.11和y=5.95x+5.83,完全致死时间分别为28、24、16 d;幼虫的相应回归方程分别为y=4.62x+10.16、y=6.08x+8.33和y=6.66x+21.67,完全致死时间分别为20、16、12 d;蛹的相应回归方程为y=3.69x+3.81、y=4.11+3.89和y=5.87x+13.33,完全致死时间分别为28、24、20 d;成虫的相应回归方程分别为y=6.33x-1.67、y=5.87x+13.33和y=7.29x+15.56,完全致死时间分别为16、16、...     

基于数字图像处理技术糙出白率和碾白率检测

通过扫描获取不同碾白时间下的大米图像,提取大米图像信息,分析大米图像信息与糙出白率和碾白率之间的相关性。结果表明:B平均值同糙出白率、H平均值同碾白率的相关系数较高,分别为-0.984 6、-0.986 1;然后建立B平均值同糙出白率、H平均值同碾白率的回归方程,分别为y=-0.302 5x+135.733,R2=0.965 6;y=-0.132 9x+105.401,R2=0.968 9。用建立的回归方程预测糙米糙出白率和碾白率,通过F检验和t检验表明,预测的糙出白率和碾白率与实际检测值是一致的.     

2014—2016年湖南省毒蕈中毒的局部空间回归分析

目的 通过对湖南省毒蕈中毒的时空分析及影响因素研究,为毒蕈中毒的防控提供科学依据。方法 收集2014—2016年湖南省122个区(县)的毒蕈中毒监测数据,利用ArcGIS 10.2软件建立病例地理信息数据库,进行空间回归分析。结果 2014—2016年湖南省122个区(县)共报告毒蕈中毒4 081例,年均报告发病率为2.01/10万,病死率为0.61%(25/4 081),多数病例集中发生在6～9月。2014—2016年湖南省各区县毒蕈中毒发病存在空间聚集性,全局Moran''s I为0.327,P<0.01。毒蕈中毒发病情况与空间回归分析显示,毒蕈中毒发病情况与年平均温度、人均卫生机构数、中学生人数呈正相关,与中学教职工人数呈负相关。结论 湖南省是我国毒蕈中毒高发地区。湖南省毒蕈中毒发病存在空间聚集性,年平均温度、中学生人数、人均卫生机构数在空间层面上对毒蕈中毒发病具有一定程度的正向影响作用。中学教职工人数对发病呈现负向影响作用。     

Release of formaldehyde and melamine from tableware made of melamine-formaldehyde resin

The relationship between the concentrations of formaldehyde and melamine released into 4% acetic acid from dishes and bowls made of melamine-formaldehyde resin was determined. The average concentrations in the migration solution after the sample had been treated at 60, 80, and 95 degrees C for 30 min with 4% acetic acid were 0.0 +/- 0.1, 0.5 +/- 0.4 and 3.0 +/- 2.2 ppm, respectively for formaldehyde and 0.04 +/- 0.07, 0.21 +/- 0.20 and 1.19 +/- 1.18 ppm, respectively for melamine. The correlation between the concentrations of formaldehyde and melamine released at 95 degrees C was y=0.4858x-0.2728 (r=0.8860), where y is melamine concentration (ppm), x is formaldehyde concentration (ppm) and r is the correlation coefficient. The molar concentration ratios of formaldehyde to melamine (F/M ratio) were 15.4 +/- 11.6 at 80 degrees C and 14.9 +/- 10.1 at 95 degrees C. Hence the release of both migrants was affected by temperature but the F/M ratio was not affected. The release of both compounds was was increased on repetition of the migration test at 95 degrees C but their concentrations remained constant after the tenth and seventeenth repetitions of the treatment. During this period, the F/M ratio decreased according to the equation 1n y=-1.4344 1n x+3.7814 (r=-0.9984) for a sample before the tenth repetition of the treatment and remained between 1.7 and 1.9 after the twelfth repetition, where y is the F/M ratio and x is the number of repetitions of the treatment.     

The relationship between milk yield and the incidence of some diseases in dairy cows

Logistic regression models were used to examine the relationship between milk yield and incidence of certain disorders. Lactations (n = 2197) of 1074 Holstein-Friesian cows from 10 dairies (25 to 146 cows per dairy) in Lower Saxony were studied. The 305-d yield from the previous and current lactations served as the standards for milk yield. Eight disorder complexes were considered: retained placenta, metritis, ovarian cysts, mastitis, claw diseases, milk fever, ketosis, and displaced abomasum. Each disorder complex was modeled separately. In addition to milk yield, the influences of the lactation number, the calving season and the other disorder complexes were examined with the "herd" factor taken into account. A correlation between retained placenta, mastitis, and milk fever to milk yield during the previous lactation was found to be probable and for ketosis and displaced abomasum such a correlation was found to be possible. A connection to the yield in the current lactation was shown for ovarian cysts, claw diseases, and milk fever. No relationship to milk yield existed for metritis. An influence of the lactation number was also demonstrated in various models. Single models allowed a demonstration of the influences of both milk yield and lactation number. Limitations of the model types are discussed.     

EFFECT OF WEIGHT,TEMPERATURE AND SKINNING OF BROILER DRUMSTICKS ON BATTER AND BREADING ADHESION1

The relationship of the original weight of a broiler drumstick to % coating pickup, % cooking loss, % crumb loss, and % overall yield was studied. No significant correlation was found between size and % coating pickup, but there were significant correlations between the other variables. Correlation between original weight of a broiler drumstick and cooking loss was highly significant (P = .0001), and the regression equation y = 32.58 – 0.1081x was calculated. Similiarly, the relation between % crumb loss and original weight of a drumstick was highly significant (P = .0001) and the regression equation y =−0.2196 + 0.0207x was calculated. The % overall yield also was dependent upon original weight (P = .0003). The regression equation y = 72.97 – .1010x describes that relationship. The effect of temperature of broiler drumsticks prior to batter and breading, on % coating pickup, % cooking loss, % crumb loss, and % overall yield was studied. The % coating pickup of drumsticks coated at room temperature (23C) was not significantly different (P<0.05) from those coated at refrigerator temperatures (4C), with means of 5.34%, and 5.05%, respectively. Those drumsticks coated at 110C had a lower % coating pickup, possibly due to a drier skin surface and those coated at −15.5C had the least coating pickup. Poultry parts frozen before being coated had the highest cooking loss and those coated at 23C and 4C had significantly lower % cooking losses of 24.52% and 24.55%, respectively. The % crumb loss of broiler parts coated at 4C, 23C, and −15.5C of 1.72%, 1.52%, and 1.50% was significantly higher than drumsticks coated at 110C with 1.13% crumb loss, but the drumsticks coated frozen had very little coating pickup in the first place. The % overall yield of drumsticks coated at 23C (79.30%), and 4C (78.78%) was significantly higher than those coated at 110C (76.40%), and those had a significantly higher yield than drumsticks coated at −15.5C. The same variables used to study size and temperature effects were used to study differences in broiler drumsticks with and without skin, at 4C. Broiler drumsticks coated without skin had significantly increased coating pickup and decreased crumb loss over drumsticks with the skin intact. Cooking losses were significantly lower for drumsticks coated with the skin on, but the % overall yields of 7Z97% for those without skin, and 78.78% for those with skin were not significantly different.     

絮凝活性菌株培养条件的响应面优化

选取对甘薯淀粉具有明显絮凝效果的活性菌株,利用响应面分析法对其培养条件进行优化。在单因素实验的基础上,采用Box-Behnken中心组合实验设计,以初始pH、接种量、培养温度和培养时间四个因素为响应因子,絮凝率为响应值分析各因子与絮凝率之间的影响关系。最终建立二次回归方程为Y1=-103.602+5.166X1+5.848X2+8.312X3+0.0580X4-1.028X1X1-0.14X1X2+0.263X1X3+0.0185X1X4-0.141X2X2-0.097X2X3-0.003X2X4-0.166X3X3-0.002X3X4-0.0006X4X4,并得到相关系数R2=0.9550,对各因子的显著性及交互作用分析后,确定了最佳培养条件为:初始pH6.0、接种量8%、培养温度27℃、培养时间48h。在此培养条件下絮凝率的理论值为48.72%,重复验证值为48.65%。     

便携近红外检测仪测定鲜猪肉水分含量的研究

采用课题自主研发的便携近红外检测仪,对市售15份猪背最长肌进行测定,通过试验,研究不同波长下测定的电压值与猪肉水分含量测定值之间的关系。结果表明,市售猪肉在室温下(25℃)放置2d,水分含量逐渐减少,便携近红外检测仪测定的电压值逐渐升高,在810、850、880nm的波长下水分含量和电压值相关性检验显著(0.01相似文献   

黄背木耳对基质中铬的富集研究

通过添加不同浓度硝酸铬,探讨四川地区黄背木耳主栽品种(上海1号和黄耳10号)基质与子实体中铬的相关性,明确子实体对基质中铬的富集能力,为制订基质中铬限量标准提供技术支撑。实验采用在基质中人为添加不同浓度硝酸铬的方式,设计添加0、1、5、10、20 mg/kg共计5个不同浓度,按正常栽培方法进行种植,分别取5个浓度的1~3潮毛木耳子实体进行验证,验证方法采用微波消解-电感耦合等离子体-质谱法(ICP-MS),并对验证数据进行SPSS方差及回归分析。结果表明,基质灭菌前后铬含量无明显差异,1~3潮子实体对基质中铬的富集能力差异规律不明显,子实体中铬含量随基质中铬含量增加而增加,但增长趋势随着基质中铬含量的增加渐缓。两个品种子实体对基质中铬的富集方程分别为,黄耳10号:y=0.7ln(x)+0.2221,R2=0.9129;上海1号:y=1.3324ln(x)-0.9914,R2=0.9574,该回归方程可作为限量指标设定的参考。