共查询到19条相似文献,搜索用时 62 毫秒
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利用马铃薯淀粉制备酶变性淀粉,在单因素试验的基础上选择了淀粉浆浓度、酶解温度、酶解时进行三素三水平的正交试验,确定了较优的淀粉酶解工艺条件,使酶解淀粉的DE值稍大于2。再确定酶变性淀粉的糊化温度和糊化时间,制备用采模拟油脂的变性淀粉,以减少食用者的热量摄入,更加有利于人体健康。 相似文献
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印刷、纸张加工和许多产品应用都将使纸页或纸板的内部或层间受到压力、冲击力等,这些都将引起诸如表面起毛、起泡或层间分层的结构失效。这些结构失效的共同点是:1)高速的压力负载,2)受作用力的时间较短。很多情况下是微秒的百分之一。有以上共同点的纸张结构失效可以用内结合强度值的大小来表达.这些测试的结果与在印刷或纸张加工过程中遇到的内部结构失效有密切关系, 相似文献
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麦草化学浆纤维柔软度与纸页Z向强度和物理强度的关系 总被引:3,自引:0,他引:3
我国森林资源匮乏,造纸的原材料短缺,随着近十几年国民经济的快速发展,对纸制品的需求量越来越大,而这种需求量正在以每年7.1%的速度在增长。1997年我国一年的人均纸张消费量为26.5公斤,远低于当年 相似文献
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对半纤维素和木素在非木材纤雏的纸张抄造过程中的作用进行了阐述,研究了麦草浆中脱除和保留一定量的半纤维素和木素对纸张物理强度和纸页性能的影响。 相似文献
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对半纤维素和木素在非木材纤维的纸张抄造过程中的作用进行了阐述,指出了脱除和保留一定量的半纤维素和木素对纸张物理强度和纸页性能的影响。 相似文献
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使用阴离子淀粉改善纸袋纸强度 总被引:1,自引:0,他引:1
为了改善纸袋纸的强度,提高产品档次,增加企业的经济效益,江西省轻工研究所与吉水造纸厂合作进行了添加增强剂含氮磷酸酯双改性阴离子淀粉PUS01的实验室试验和生产试验,取得了提高纸张强度、降低生产成本的较好效益。1实验11原料。100%马尾松枝桠材硫酸盐木浆,硬度30~34KMnO4值,取自吉水造纸厂。12打浆。在23升小型荷兰式打浆机中进行打浆,浓度2%,打浆度30~32°SR。13抄片。将来浆洗净接近中性,稀释后加入阴离子淀粉糊化液,1分钟后在纸页成形器上抄片,定量为100克/米2。在恒温恒湿状态下测定各项物… 相似文献
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利用中温α-淀粉酶对玉米淀粉进行酶降解处理,获得了不同黏度(相当于降低淀粉分子质量)的改性淀粉,并用其对箱纸板表面进行施胶,分析该淀粉向箱纸板内部的渗透能力,并探讨淀粉渗透程度对箱纸板挺度的影响。研究表明,在酶改性淀粉黏度75 mPa·s、施胶温度70℃、施胶量8 g/m2、施胶液浓度12%条件下进行表面施胶,该酶改性淀粉能通过纸张孔隙渗入纸板内部,成纸环压指数提高至11.51 N·m/g(提高23.8%),挺度指数提高至232.6 N·m3/g(提高77.6%)。 相似文献
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A new method of physical modification of starch in the presence of high concentrated salt solution is presented, called “Osmotic Pressure Treatment” (OPT). OPT was introduced in order to produce the same physically modified products as obtained by conventional heat‐moisture treatment (HMT) of starch. Potato starch was selected for the comparative study of the two methods. For the OPT method, potato starch was suspended in a saturated solution of sodium sulfate and heated in an autoclave at 105°C and 120°C ,which corresponded to the calculated osmotic pressures of 328 and 341 atm (332 and 345 bar, respectively) (assuming sodium sulfate dissociates completely) for 15, 30 and 60 min, respectively. For the HMT method, starch with 20% moisture content was placed in a Duran bottle, then the same heat treatment method in the autoclave was applied. Light and scanning electron microscopy (SEM) showed that OPT of starch changed the shape of the starch granules to a folded structure, while the starches remained unchanged after HMT. The RVA viscogram for the OPT starch exhibited a decrease in the peak viscosity without a breakdown and an increase of the pasting temperature when increasing the temperature and time, which was in an agreement with the viscosity patterns for the HMT starches. X‐ray diffraction patterns were altered from B to A+B for the HMT and from B to A type for the OPT starch when treated at 120°C. After OPT, the gelatinization temperatures (To, Tp, and Tc) of the starch increased significantly with increasing temperature and time, whereas only the Tc of starch increases after HMT. The biphasic broadening of the peaks (high Tc‐To) can be explained by an inhomogeneous heat transfer during HMT. Narrow peaks in the DSC curve can be an indication for a better homogeneity of the OPT samples. However, both methods provide a similar decrease in the gelatinization enthalpy (ΔH). The amylose‐amylopectin ratio calculated from the HPSEC patterns was strongly increased for HMT starches at 105°C for 60 min and 120°C for 30 min and decreased after treatment at 120°C for 60 min. For OPT starches the ratio was strongly increased at 120°C for 15 min and decreased after prolong heating. The OPT provides a uniform heat distribution in the starch suspension. This allows the modified starch to be produced on a larger scale. 相似文献