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961.
Elena Torrieri Silvana Cavella & Paolo Masi 《International Journal of Food Science & Technology》2009,44(5):890-899
In this work, the effect of temperature, oxygen, red coloration process and post-harvest storage time on the respiration rate of fresh-cut Annurca apples was studied to properly develop modified atmosphere packaging. Our results showed that the red coloration process and the post-harvest storage time did not affect the respiration rate or the respiratory quotient of fresh-cut Annurca apples in the range of temperature studied (5–20 °C). A Michaelis–Menten-type equation, with the model constants described by means of an Arrhenius-type relationship, was used for predicting respiration rate on varying the temperature and O2 concentration in the head space. The maximal respiration rate (mL kg h−1 ) (RRmax ) and the O2 % corresponding to values estimated at the reference temperature (12.5 °C), i.e. the average of the experimental temperature ranges, were, respectively, 6.77 ± 0.1 mL kg−1 h−1 and 0.68 ± 0.07% v/v, and the activation energy of the aerobic respiration rate of fresh-cut Annurca apples was estimated at 51 ± 1 kJ mol−1 . The model works well to develop a modified atmosphere for fresh-cut Annurca apples. 相似文献
962.
In the past decade, a major transition evolved in the Dutch fresh meat industry with ramifications for the entire meat business. In 1995, more than 95% of all fresh meat products for consumers were either sold loose or packed in the traditional way, i.e. on a white styrofoam tray with stretch wrap. Almost a decade later, about half of the meat industry has adapted the modified atmosphere packaging (MAP) technology. Strikingly, the first trials with this technology had already been conducted in The Netherlands in 1964, but it took four decades for the technology to conquer the Dutch meat industry. This paper argued that the partial adaptation of MAP diminished the product losses in fresh meat sales and hence the environmental impact of meat production and consumption. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
963.
建立电路方程方法的起源、演变与发展 总被引:1,自引:0,他引:1
叶庆云 《电气电子教学学报》2000,22(3):34-36
以线电电阻电路为例,从教学角度研究了建立电路方程方法的起源、演变与发展。 相似文献
964.
965.
966.
B Das K Ramakrishna G D Verma R S Tiwari O N Srivastava 《Bulletin of Materials Science》1991,14(3):585-592
The second generation of high temperature superconductors typified by Bi2Sr2Ca
n−1Cu
n
O2n+4 and Tl2Ba2Ca
n−1Cu
n
O2n+4 exhibits curious structural properties which have direct relevance to the superconducting behaviour particularly transition
temperature (T
c
). The present paper reports on investigations of structural properties at microlevel in Bi-bearing HTCS. We have found curious
structural characteristics which manifests itself in the form of transformation froma
p
×a
p
×c to (2)1/2
a
p
×(2)1/2
a
p
×c through the loss of calcium atoms and the formation of five-fold modulated phase alongb through the loss of Ca and Sr atoms. We have also found the evidence of high periodicities (n=4) Bi2Sr2Ca3Cu4O12. The microstructural characteristics of HTCS showing the higherT
c
(R=0) ∼ 120 K exhibits unusual characteristics. 相似文献
967.
968.
Hayato Takasago Eishi Gofuku Mitsuyuki Takada Yoshiyuki Morihiro 《Journal of Electronic Materials》1989,18(5):651-655
When electric resistivity of Thick Film Resistor (TFR) is adjusted to the desired value, laser beam is irradiated onto the
resistor material so that a part of the resistor material is instantaneously vaporized and cut away. This conventional laser
trimming method to adjust the resistivity of TFRs is an indispensable technique for manufacturing elec-tronic devices such
as hybrid ICs. A peculiar phenomena was revealed by us, that is, when specially selected pulse laser beams were irradiated
to TFR, the TFR was surface modified without cutting grooves, and then resistivity of the TFR was decreased. We completed
the advanced laser process to apply this peculiar phenomena. 8 By comparing with conventional trimming processes, we can show
prominent features of the advanced process, for example, resistivity of fine size TFR (300 micrometers-width and under) can
be easily controlled. The decrease in resistivity of the TFR is considered to result from the decrease in specific resistivity
of glass in the TFR. Because it is considered that the glass in the TFR is heavily doped with ruthenium impurities during
the surface modification due to results of morphology observations and x-ray diffraction analysis. We have applied this advanced
laser process to fine size TFR (300 micrometers-width), and developed high density hybrid ICs. 相似文献
969.
文章介绍了在蒙(城)蚌(埠)路路面施工中,为保证沥青路面施工质量,有针对性地对原材料、拌和站生产以及摊铺碾压的有关方面质量控制要点进行了分析,并提出了处理办法。 相似文献
970.
为分析多聚磷酸掺量对SBS/多聚磷酸复合改性沥青高温流变特性的影响,对比复合改性沥青与基质沥青、SBS改性沥青流变特性的差异,本文采用SK90号基质沥青、制备4.5%SBS改性沥青以及SBS/多聚磷酸复合改性沥青。对沥青试样进行60℃频率扫描和30℃-60℃温度扫描试验,分析沥青结合料复数模量、相位角随加载频率和温度的变化规律。结果表明:SBS改性沥青、SBS/多聚磷酸复合改性沥青的复数模量值远大于基质沥青,SBS/多聚磷酸复合改性沥青的复数模量随着多聚磷酸掺量的增多而增大;SBS改性沥青和SBS/多聚磷酸复合改性沥青的相位角随荷载作用频率上升而迅速增大;SBS改性沥青和SBS/多聚磷酸复合改性沥青的温度敏感性较基质沥青有了显著的改;3.5%SBS+1.6%PPA复合改性沥青的复数剪切模量大于改性剂掺量为4.5%的SBS改性沥青。 相似文献