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991.
绿色切削加工技术的研究   总被引:7,自引:2,他引:7  
分析了传统切削加工方式对环境的危害,提出了绿色切削加工应采取的措施和一些研究课题。指出干切削等加工方式是控制环境污染的绿色制造工艺。  相似文献   
992.
大孔树脂对豆粕中异黄酮吸附特性的研究   总被引:1,自引:0,他引:1  
选用高效液相色谱法及紫外分光光度法检测溶液中大豆异黄酮的含量。比较3种不同型号大孔树脂对大豆异黄酮的吸附解吸性质,从中筛选出效果较好的ADS-21型树脂进行静态及动态动力学特性研究,得到该树脂在室温条件下对大豆异黄酮的吸附及解吸动力学曲线。  相似文献   
993.
郑仁德 《饮料工业》2007,10(3):45-49
通过热灌装线洁净室设计的基本要求、良好的GMP控制与洁净室运行管理、严格的检测监控措施3方面介绍了控制灌装环境的空气清洁度的有效措施。从而为洁净室在热灌装线的应用提供了较有借鉴意义的资料。  相似文献   
994.
吕岳文  杨洁  蒋新月 《食品科学》2010,31(21):114-118
对驴初乳物理性质和化学组成研究。结果表明,驴初乳的相对密度、折光度、电导率、酸度均高于常乳,而pH 值低于常乳;驴初乳中蛋白质、灰分、脂肪含量均随泌乳期延长呈下降趋势;分娩后第一次(6h)所挤初乳中乳糖含量最低,之后随泌乳期延长乳糖含量呈上升趋势;随泌乳期的延长,初乳中各项指标逐渐接近常乳。应用亲和色谱法测定驴初乳免疫球蛋白含量,结果表明,随泌乳期的延长驴初乳中IgG 含量呈下降趋势。  相似文献   
995.
通过对江南名点——粽子的原料选择、制作工艺、保存环境的探讨,揭示了粽子在通常.条件下不容易变质的原因,并确定用传统方法制作的粽子在通常环境下的保质期限,为其他传统点心的保鲜提供参考。  相似文献   
996.
BACKGROUND: Isoflavone content in soybean seeds is strongly influenced by both environment and genotype. However, little is known about the effect of environment and genotype on isoflavones in germ versus cotyledons. To determine the effect of temperature and soil moisture status during soybean seed development on seed isoflavone concentration and composition, a set of two French and three US cultivars of similar maturity were grown in the greenhouse. At the R6 growth stage, plants were subjected to one of three night/day temperature regimes (13/23°, 18/28° or 23/33 °C) in either optimal or sub‐optimal soil water conditions. RESULTS: In cotyledons, a three‐ to six‐fold variation in total isoflavone content was observed between the high and low temperature treatments, whereas the germ contents had less than a two‐fold variation. Soil water supply had less effect than temperature on the isoflavone contents and compositions. In both seed parts, the isoflavone concentrations were highly dependent on the cultivar. CONCLUSION: These results show that isoflavone content and composition in cotyledon and germ are unrelated and it should be possible to independently manipulate these seed traits through plant breeding and crop management systems. Copyright © 2007 Society of Chemical Industry  相似文献   
997.
Aroma compounds emitted from elderberry juices processed from seven cultivars were collected by the dynamic headspace technique and analysed by GC–FID and GC–MS. Forty aroma compounds were identified and quantified, including nine compounds which had not previously been detected in elderberry juice. Significant differences were found among cultivars in the concentration levels of 30 compounds. The sensory characteristics of the individual aroma compounds in elderberry juice were determined by a GC‐sniffing technique, and the compounds were grouped according to their odour. The characteristic elderberry odour is due to dihydroedulan and β‐damascenone, of which the former occurs in relatively high concentrations in the headspace of elderberry juice. The fruity group consisted of aliphatic alcohols and aldehydes and aromatic esters, of which 1‐pentanal, 2‐methyl‐1‐propanol, 2‐ and 3‐methyl‐1‐butanol, 1‐octanal, 1‐octanol and methyl and ethyl benzoate contributed with fruity notes. In the flowery group, 1‐nonanal, nerol oxide and (Z)‐ and (E)‐rose oxide contributed with characteristic elder flower odour, whereas other flowery notes were associated with hotrienol, linalool and α‐terpineol. Fresh and grassy odours were correlated with 1‐hexanal, (E)‐2‐hexen‐1‐al, (Z)‐3‐hexen‐1‐ol, (E)‐2‐hexen‐1‐ol and (E)‐2‐octen‐1‐al of the grassy group, whereas 1‐octen‐3‐ol and 1‐octen‐3‐one of the agrestic group contributed significantly with the characteristic aroma of mushrooms. © 2000 Society of Chemical Industry  相似文献   
998.
Accurate forecasting of dairy cow milk yield is useful to dairy farmers, both in relation to financial planning and for detection of deviating yield patterns, which can be an indicator of mastitis and other diseases. In this study we developed a dynamic linear model (DLM) designed to forecast milk yields of individual cows per milking, as they are milked in milking robots. The DLM implements a Wood's function to account for the expected total daily milk yield. It further implements a second-degree polynomial function to account for the effect of the time intervals between milkings on the proportion of the expected total daily milk yield. By combining these 2 functions in a dynamic framework, the DLM was able to continuously forecast the amount of milk to be produced in a given milking. Data from 169,774 milkings on 5 different farms in 2 different countries were used in this study. A separate farm-specific implementation of the DLM was made for each of the 5 farms. To determine which factors would influence the forecast accuracy, the standardized forecast errors of the DLM were described with a linear mixed effects model (lme). This lme included lactation stage (early, middle, or late), somatic cell count (SCC) level (nonelevated or elevated), and whether or not the proper farm-specific version of the DLM was used. The standardized forecast errors of the DLM were only affected by SCC level and interactions between SCC level and lactation stage. Therefore, we concluded that the implementation of Wood's function combined with a second-degree polynomial is useful for dynamic modeling of milk yield in milking robots, and that this model has potential to be used as part of a mastitis detection system.  相似文献   
999.
Postharvest decay of fruits, vegetables, and grains by fungal pathogens causes significant economic losses. Infected produce presents a potential health risk since some decay fungi produce mycotoxins that are hazardous to human health. Infections are the result of the interplay between host resistance and pathogen virulence. Both of these processes, however, are significantly impacted by environmental factors, such as temperature, UV, oxidative stress, and water activity. In the present review, the impact of various physical postharvest treatments (e.g., heat and UV) on the viability and virulence of postharvest pathogens is reviewed and discussed. Oxidative injury, protein impairment, and cell wall degradation have all been proposed as the mechanisms by which these abiotic stresses reduce fungal viability and pathogenicity. The response of decay fungi to pH and the ability of pathogens to modulate the pH of the host environment also affect pathogenicity. The effects of the manipulation of the postharvest environment by ethylene, natural edible coatings, and controlled atmosphere storage on fungal viability are also discussed. Lastly, avenues of future research are proposed.  相似文献   
1000.
以16S rRNA和18S rRNA基因为分子标记,应用高通量测序技术分析了福建永春老醋发酵中(Y1)、1个月成品(Y2)、1年陈酿(Y3)和10年陈酿(Y4)共4个不同生产阶段中的细菌与真菌群落多样性.结果表明,对于细菌组成,Y1、Y2和Y3三个阶段优势菌纲皆为 α-变形菌纲(Alphaproteobacteria)...  相似文献   
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