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911.
以玫瑰花卉浸提液和白酒为酒基,加入多种香料,陈酿数月配制成玫瑰花味美思,研究了玫瑰花味美思的最佳配方。通过正交试验、感官品评、理化指标测定等,研究了浸提工艺条件、稳定性和澄清处理效果等问题。结果表明:玫瑰花味美思的最佳配方是玫瑰花料水比1∶60、温度70℃、时间40min的浸提液,按糖分5%、酒精15%加入白砂糖和白酒,加入苦艾1.18g/L、肉桂0.79g/L、豆蔻0.13g/L、橙皮0.13g/L等。混合液pH值为3.5,陈酿3个月,经不同澄清剂澄清处理,得出40mg/L单宁与150mg/L蛋清配比的复合澄清剂澄清效果较好的结论。GC-MS分析结果表明,味美思香味醇和、浓郁,暴冲感大大减弱。  相似文献   
912.
在连续采煤机的变频调速系统中,变频器会产生和受到各种电磁干扰。指出了变频调速系统中主要的干扰源及干扰的途径,分析干扰信号的传播方式,提出了抗干扰的实际解决方法,探讨了在连续采煤机变频器应用系统设计和安装中抑制干扰的具体措施。  相似文献   
913.
在陶瓷超低温釉纳米助熔粘接剂配方研究的基础上研究了粘接剂操作性能,釉浆流动性、釉重随釉浆含水量及粘接剂用量的变化关系;研究了制得成品瓷的铅镉溶出性能.采用透射电子显微镜、X射线衍射物相分析,氮气吸附对纳米助熔剂的主要成分纳米氧化硅进行了表征,结果表明:纳米氧化硅为无定性粉体,所提供的国产"中国红"低温釉助熔粘接剂在用量为13.04%时水含量可控范围可为50.2%到51.8%,该控制范围比英国庄信万丰的控制范围更宽,在此范围可实现单个郎酒瓶(500 g容积)釉重在4.25~5.00 g之间,所配制的釉浆具有较好的流动性与触变性;烧制出的酒瓶铅镉溶出量符合国家标准.  相似文献   
914.
The bglS gene encoding endo-1,3-1,4-β-glucanase from Bacillus subtil& was cloned and sequenced in this study. The bglS expression cassette, including PGK1 promoter, bglS gene fused to the signal sequence of the yeast mating pheromone a-factor (MFals), and ADH1 terminator with G418-resistance as the selected marker, was constructed. Then one of the PEP4 allele of Saccharomyces cerevisiae WZ65 strain was replaced by bglS expression cassette using chromosomal integration of polymerase chain reaction (PCR)-mediated homologous recombination, and the bglS gene was expressed simultaneously. The recombinant strain S. cerevisiae (SC-βG) was preliminarily screened by the clearing hydrolysis zone formed after the barley β-glucan was hydrolyzed in the plate and no proteinase A (PrA) activity was measured in fermenting liquor. The results of PCR analysis of genome DNA showed that one of the PEP4 allele had been replaced and bglS gene had been inserted into the locus of PEP4 gene in recombinant strains. Different endo-1,3-1,4-β-glucanase assay methods showed that the recombinant strain SC-βG had high endo-1,3-1,4-β-glucanase expression level with the maximum of 69.3 U/(h·ml) after 60 h of incubation. Meanwhile, the Congo Red method was suitable for the determination of endo-1,3-1,4-β-glucanase activity during the actual brewing process. The current research implies that the constructed yeast strain could be utilized to improve the industrial brewing property of beer.  相似文献   
915.
Objective: To determine the effects of albumin administration on lung injury and apoptosis in traumatic/hemorrhagic shock (T/HS) rats. Methods: Studies were performed on an in vivo model of spontaneously breathing rats with induced T/HS; the rats were subjected to femur fracture, ischemia for 30 min, and reperfusion for 20 min with Ringer's lactate solution (RS) or 5% (w/v) albumin (ALB), and the left lower lobes of the lungs were resected. Results: Albumin administered during reperfusion markedly attenuated injury of the lung and decreased the concentration of lactic acid and the number of in situ TdT-mediated dUTP nick-end labelling (TUNEL)-positive cells. Moreover, immunohistochemistry performed 24 h after reperfusion revealed increases in the level of nuclear factor κB (NF-κB), and phosphorylated p38 mitogen-activated protein kinase (MAPK) in the albumin-untreated group was down-regulated by albumin treatment when compared with the sham rats. Conclusion: Resuscitation with albumin attenuates tissue injury and inhibits T/HS-induced apoptosis in the lung via the p38 MAPK signal transduction pathway that functions to stimulate the activation of NF-κB.  相似文献   
916.
Application of NIR spectroscopy for firmness evaluation of peaches   总被引:1,自引:0,他引:1  
The use of near infrared (NIR) spectroscopy was proved to be a useful tool for quality analysis of fruits. A bifurcated fiber type NIR spectrometer, with a detection range of 800-2500 nm by InGaAs detector, was used to evaluate the firmness of peaches. Anisotropy of NIR spectra and firmness of peaches in relation to detecting positions of different parts (including three latitudes and three longitudes) were investigated. Both spectra absorbency and firmness of peach were influenced by longitudes (i, ii, iii) and latitudes (A, B, C). For modeling, two thirds of the samples were used as the calibration set and the remaining one third were used as the validation or prediction set. Partial least square regression (PLSR) models for different longitude and latitude spectra and for the whole fruit show that collecting several NIR spectra from different longitudes and latitudes of a fruit for NIR calibration modeling can improve the modeling performance. In addition, proper spectra pretreatments like scattering correction or derivative also can enhance the modeling performance. The best results obtained in this study were from the holistic model with multiplicative scattering correction (MSC) pretreatment, with correlation coefficient of cross-validation γcv=0.864, root mean square error of cross-validation RMSECV=6.71 N, correlation coefficient of calibration r=0.948, root mean square error of calibration RMSEC=4.21 N and root mean square error of prediction RMSEP=5.42 N. The results of this study are useful for further research and application that when applying NIR spectroscopy for objectives with anisotropic differences, spectra and quality indices are necessarily measured from several parts of each object to improve the modeling performance.  相似文献   
917.
Objective: To report a mathematical function that characterizes the double-pass line spread function (LSF) of the human eye. Determining analytical functions that represent the double-pass LSF is important because it allows modeling the optical performance of the eye, Methods: Optical section retinal images, generated in normal human eyes using a modified slit-lamp biomicroscope, were analyzed to derive the double-pass LSF by plotting the intensity distribution of laser light reflected/ scattered from the vitreoretinal interface. Three mathematical functions (Lorentzian, Gaussian, exponential) were fitted to the double-pass LSF and the root mean square error (RMSE) was calculated to provide a measure of the goodness of fit. Results: The Lorentzian function provided the best representation of the double-pass LSF of normal human eyes. The full width at half maximum (FWHM) of the Lorentzian fitted curve was positively correlated with age, indicating that the double-pass LSF broadens with age. Furthermore, the goodness of fit of the Lorentzian function was significantly better in younger subjects as compared with older subjects, suggesting that the fitted function to the double-pass LSF may vary according to age. Conclusion: The results demonstrate an age-related change in the double-pass LSF width and the goodness of fit of the Lorentzian function.  相似文献   
918.
Objective: To compare the efficacy of a short messaging service (SMS) text messaging and phone reminder to improve attendance rates at a health promotion center. Methods: A total of 1 859 participants who had scheduled appointments in the health promotion center of our hospital from April 2007 to May 2007 were enrolled in the study and randomly assigned into 3 groups: control (no reminder) group, SMS text messaging reminder group and telephone reminder group. Attendance rates and costs of interventions were collected. Results: A total of 1848 participants were eligible for analysis. Attendance rates of control, SMS and telephone groups were 80.5%, 87.5% and 88.3%, respectively. The attendance rates were significantly higher in SMS and telephone groups than that in the control group, with odds ratio 1.698, 95% confidence interval 1.224 to 2.316, P=0.001 in the SMS group, and odds ratio 1.829, 95% confidence interval 1.333 to 2.509, P〈0.001 in the telephone group. However, there was no difference between the SMS group and the telephone group (P=0.670). The cost effectiveness analysis showed that the cost per attendance for the SMS group (0.31 Yuan) was significantly lower than that for the telephone group (0.48 Yuan). Conclusion: SMS and telephone are effective reminders for improving attendance rate at a health promotion center. SMS reminder may be more cost-effective compared with the telephone reminder.  相似文献   
919.
现代汉语中的“再”和“又”都可以表示一个动作或一种状态的重复或继续,但它们并不是在所有的情况下都能互换使用。在前人研究的基础上,从句法、语义、语用等方面对副词“再”和“又”进行综合考察。  相似文献   
920.
理性行为理论认为,意愿是行为的有效预测变量;但企业社会责任相关研究表明,消费者的购买意愿与购买行为之间存在着巨大的差距。为了探究消费者响应企业社会责任行为对购买意愿的影响,并进而对购买行为的影响,以及购买意愿与购买行为之间的差距,构建了一个包含企业社会责任、购买意愿、购买行为、主动性人格与效能感的研究框架,通过情景化的自我报告问卷调查方法对研究框架进行了检验。研究结果表明:① 消费者一般会积极响应企业社会责任行为,其购买意愿部分中介企业社会责任与实际购买行为之间的关系;② 消费者由企业社会责任产生的购买意愿与购买行为之间存在较大的差距,企业社会责任可以解释25%的购买意愿,却只能解释20%的购买行为;③ 消费者主动性人格或效能感水平较高时,购买意愿对企业社会责任与购买行为之间关系的中介作用更强,可以有效减小伦理消费的意向-行为差距。  相似文献   
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