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101.
102.
高吸水性树脂在工业中的应用研究 总被引:5,自引:0,他引:5
高吸水性树脂经过检测,结果证明其无毒无菌,对人体无害,将高吸水性树脂应用一主油田钻井泥浆等工业领域的试验,已取得了满意的结果。 相似文献
103.
104.
无载体淀粉胶粘剂的研制 总被引:2,自引:1,他引:1
论述了无载体淀粉胶粘剂的研制原理、方法及技术特点。并研究了在不同反应条件下的各种影响因素。指出无载体淀粉胶粘剂是一种各方面性能都较理想的、适于生产瓦楞纸板的新型淀粉胶粘剂。 相似文献
105.
Rafael Alique Pilar Luna Teresa Hernández M. Angel Martínez 《European Food Research and Technology》2009,229(4):661-669
Atomised hot water vapour at between 46 and 54 °C for 60 min was tested as a method of delaying ripening and extending shelf
life in cv “Fino de Jete” cherimoya fruit (Annona cherimola Mill.). Heat treatment at 46 °C stimulated the respiration rate and starch degradation, induced ethylene production, increased
the accumulation of soluble sugars and α-amylase activity, and moved the onset of ethylene production (OEP) forward. Treatment
at 50 °C, and especially at 52 °C, delayed the climacteric peak and the OEP, decreased sugar and organic acid accumulation,
and reduced α-amylase and invertase activity. The results obtained indicate that temperatures higher than 48 °C slowed physiological
processes and carbohydrate metabolism and extend the shelf life of the cherimoya fruits, while temperatures higher than 52 °C
blocked ripening irreversibly. 相似文献
106.
Wang Shujun Liu Hongyan Gao Wenyuan Chen Haixia Yu Jiugao Xiao Peigen 《Food chemistry》2006,99(1):30-37
The starches separated from four different Dioscorea opposita Thunb. cultivars were investigated for morphological, thermal, crystal, and physicochemical properties, such as amylose content, swelling power, solubility and water-binding capacity properties. Amylose content of D. oppositastarches from different cultivars ranged from 20.74% to 25.94%. The shape of starch granules separated from different D. opposita Thunb. cultivars varied from round to oval or elliptic. The mean particle diameter of starches ranged from 23.39 to 26.87 μm. The transition temperatures (To, Tp and Tc) and enthalpy of gelatinization (ΔHgel) were determined using differential scanning calorimetry (DSC). To, Tp and Tc varied from 73.6 to 74.8, 78.8 to 81.0, and 83.3 to 87.2 °C, respectively. D. opposita cv. Jinchengerhao starch showed the highest ΔHgel values (12.48 J/g) while D. opposita cv. Baiyu starch showed the lowest values (8.413 J/g). The crystal type of starches separated from different D. opposita cultivars was a typical CB-type pattern. The degrees of crystallinity of the four D. opposita cultivars starches were about 50.52%, 32.99%, 33.57% and 36.16%, respectively. 相似文献
107.
高取代度羧甲基淀粉醚的制备 总被引:6,自引:0,他引:6
通过正交设计的合成试验对影响羧甲基淀粉醚取代度的各因素及它们的交互作用进行了考察,通过方差分析检验它们的显著性,研究了各因素影响淀粉羧甲基化反应的机理。在所确立的最佳反应条件下一次醚化能制备取代度高达1.70的羧甲基淀粉醚。对高取代淀粉醚作为钻井泥浆降失水剂的性能进行了初步评价。 相似文献
108.
In the present study, the ultrasonication method was used to investigate the effect of ultrasonic energy on the hydrolysis of corn, rice, and wheat starch by using the alpha-amylase enzymes produced by Bacillus species and Bacillus licheniformis. The effects of sonifier operation variables such as duty cycle and acoustic power rate on the stability of alpha-amylase enzymes and hydrolysis degrees of three types of starches were investigated at a temperature of 40°C and pH 6.5. To determine the effect of temperature with sonication on the hydrolysis process, wheat starch hydrolysis experiments were also carried out at a temperature of 50°C. Then, the relation between duty cycle and enzyme stability during hydrolysis for each enzyme at 50°C was expressed by a zero-order inactivation model. 相似文献
109.
The effects of air humidity when drying with superheated steam (SHS) were examined considering displacement by SHS. A wetted raw starch sphere (ball) was used as the model material. It was found that the humidity profile strongly affects the mass change and properties of the products. The material became porous when it was dried with pure SHS from start to finish, which differs both from products dried with high-humidity air alone, and from products dried with air followed by SHS within a few minutes. A prediction method for adiabatic saturation temperature over a wide range of humidity is also proposed. 相似文献
110.
淀粉双酶传感器的研制 总被引:2,自引:0,他引:2
报导了一种测定淀粉的酶生物传感器法,它具有检测速度快、灵敏度高、操作简便、且样品需要量少等优点。酶生物传感器是由固定化的GOD、GA酶膜和氧电极组成,测试的最佳条件为温度30℃,pH=4.4,0.2mol/L醋酸缓冲液,响应时间2min。该法的精密度、准确度均良好,线性范围0.05%~0.8%。 相似文献