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21.
The main scope of this comprehensive study is to investigate the effects of poly(p-benzophenoneoxycarbonylphenyl acrylate), poly(BPOCPA), which presenting as only graft units or both graft and ungrafted units in the matrix, on the fundamental features of isotactic polypropylene (IPP). The graft copolymerization of BPOCPA onto IPP was performed with the aid of bulk melt polymerization at varying monomer content levels ranging from 5% to 40%. The thermal behavior, crystal quality, mechanical performance, and surface morphology of the samples were investigated by means of differential scanning calorimeter, X-ray diffractometer (XRD), universal mechanical test, and scanning electron microscope (SEM) techniques. Thermal analyses depicted that there existed the noteworthy enhancements in both crystalline melting temperatures and percent crystallinities of matrix polymers. Furthermore, according to XRD results, a and b parameters increased significantly at low percentages of the graft units, while the parameter c decreased in all products in consistence with the content. As for the mechanical characterization, the grafting led to remarkable improvements in modulus, tensile and impact strength of the products. SEM micrographs indicated that the samples were completely homogeneous without any phase separation and the products exhibited brittle nature with some ductility. 相似文献
22.
将新开发的高效前处理、染色助剂应用于针织物实用高效漂染工艺,探讨其应用工艺、产品质量及节能减排效果。分析各类前处理碱氧一浴工艺的特点、应用特性及节能减排效果;阐述涤棉针织物练染一浴工艺,免还原清洗工艺,棉针织物活性染色与抛光一浴工艺及活性染色后皂洗酶后处理工艺。并与相应的传统工艺对比其工艺曲线、质量水平、节能减排效果及污染物浓度降低情况。客观评价各类工艺的优缺点,建议生产厂家根据产品质量要求,选用相应高效助剂,并结合实际生产设备优化工艺后使用,节能减排效果将更加显著。 相似文献
23.
Qin-yu Zhou Shan Zhao Yan-yan Huang Jin-shuang Hu Jia-hua Kuang Dong-mei Liu Charles S. Brennan 《International Journal of Food Science & Technology》2021,56(6):2992-3003
Yogurt preserves and enhances nutritional value of milk. In this study, we have compared several strains to determine the physicochemical, sensory, rheological and aroma characteristics of different yogurts. We used Lactobacillus gasseri LGZ 1029 (LG), commercial probiotic L. rhamnosus (LGG) and traditional fermentation strains Streptococcus thermophilus and L. bulgaricus (SL). Results showed that the flavour and texture characteristics of mixed-strain yogurts were obviously better than in single-strain yogurts. Addition of LG increased pseudoplastic behaviour, as shown by Herschel–Bulkley model analysis of rheological behaviour. The LG + SL group also had both the highest viscosity consistency index and thickening ability. In addition, a total of 57 volatile compounds were detected in yogurts and the fermentation with the addition of LG was mainly affected by ketones. Our study suggested that a yogurt with new attributes can be produced by using LGZ 1029. 相似文献
24.
Guzel Muhammed Huseyin Unal Recep Emre Onder Ahmet Sen Muhammed Arif Kose Faruk 《Journal of Mechanical Science and Technology》2021,35(3):1301-1308
Journal of Mechanical Science and Technology - The energy demand of world is increasing worldwide because of increasing population and developing technology. The use of environmentally friendly... 相似文献
25.
Feng Wang Min Yao Haoyong Kan Jianping Kuang Ping Li Jiashuo Zhang Yixin Zhang 《中国化学工程学报》2021,28(12):3110-3116
Coal ash melting characteristics has a direct impact on the smooth operation of entrained gasifier. Mineral conversion of coal ash is very significant to be investigated, because the mineral can affect the melting temperature and viscosity under high temperature conditions. In this paper, the effects of different Al2O3/CaO on the mineral conversion, melting temperature and viscosity of Ningdong coal ash are studied by the combination of experiment and simulation. The trend of melting temperature decreases firstly and rises with increasing Al2O3/CaO. The ash melting point reached to the lowest when the ratio is 1.23. XRD and Factsage software are used to analyze crystallization behavior of samples. The results show that the content of anorthite, albite and corundum increases and subsequently decreases, while the content of mullite decreases firstly and then rises with increasing Al2O3/CaO. High content with CaO can contribute to form albite and anorthite of low-melting. Besides, high content with Al2O3 can tend to produce mullite of high-melting. The results of experimental and simulation are basically the same, which lays a foundation for the melting characteristics of Ningdong coal ash and can provide technical support for the smooth operation of the entrained-gasifier. 相似文献
26.
27.
针对采用传统参数估计方法得到的模型拟合误差较大的问题,建立多重威布尔混合分布参数估计的非线性最小二乘模型,并提出基于模拟退火(SA)思想的自适应粒子群(PSO)算法进行求解。在PSO算法优化过程中,采用自适应方法调整惯性权重和加速因子,加快其收敛速度;引入模拟退火机制,根据Metropolis准则确定最优粒子的取舍,改善其全局搜索能力。将该方法应用到某型柴油机喷油器失效分布的参数估计中,并与图解法、基于Levenberg-Marquardt的非线性最小二乘法、标准PSO算法、自适应PSO算法求解的结果进行比较,分析所提方法的优化性能及精度。结果表明,该方法能够有效提高多重威布尔混合分布模型参数估计的精度和效率。 相似文献
28.
We have developed a digitally operated addressing and control module (DACM) for addressing and controlling of equipment from a remote computer using a communication protocol developed in-house. This is useful for automation of an experiment that uses multiple equipment in a pre-decided synchronized manner. We also report design of a multipurpose high voltage direct current (DC) source that provides output of 0–100 V with an average stability of 1.90 (36) mV and has minimum step size of 3 mV. Operation of the DACM is examined by selecting the desired equipment, which in this case is the dc source, and remotely controlling its output from a computer. We also show that this can generate voltage with different waveforms within a 0–10 Hz frequency bandwidth. Such computer controlled ultra-stable high voltage sources tuneable to any arbitrary waveforms at low frequencies have many applications such as, driving a piezo for smooth scanning of laser frequencies, tuning length of a Fabry–Perot cavity, biasing of the electrodes in an ion trap and so on. 相似文献
29.
Zhuo Zhang Sen Peng Xiaoqi Sun Yu Jie Hongfei Zhao Baoqing Zhu 《Drying Technology》2020,38(14):1843-1856
AbstractThis study constructed a β-galactosidase (β-gal) liposome model instead of bacterial cells to optimize spray-drying protectants and parameters. The screened protectant combination consisted of 35?g/L monosodium glutamate, 50?g/L sucrose, and 35?g/L maltodextrin. The optimal parameters for spray drying were 130?°C inlet air temperature, 7.5?mL/min feed flow rate, and 150?mL optimal protectant combination. The viability of the five lactic acid bacteria strains spray-dried with the optimized protectant and parameters was over 50%. Lactobacillus helveticus strain LH-9’s mechanism of resistance to spray-dry treatment was investigated in the presence of the optimal protectant combination. 相似文献
30.
使用Design-expert软件对影响立式搅拌磨机磨矿产品中间粒级(-0.038+0.010 mm)含量的磨矿时间、立式搅拌磨机转速、磨矿浓度三个因素进行设计及优化.结果显示,拟合的多元线性回归方程为y=-860.84625+52.45375A+0.44685B+18.08074C-0.0121875AB-0.272AC-0.0014825BC-3.7525A2-8.3875×10-5 B2-0.1651C2,中间粒级含量的最佳条件为磨矿时间1.94 min,搅拌器转速2138.05 r/min,磨矿浓度43.56%,该条件下可得到中间粒级含量预期值为61.48%,实际中间粒级含量可达61.68%,实际值与模拟值差异小于1%.最佳磨矿方案与响应曲面试验设计交叉方案中最佳方案相比,中间粒级提高了1.08%.因此,通过建立数学模型确定最佳的操作参数,可以提高磨矿产品质量,增加进入浮选流程的可选粒级,并对提高后续选别指标提供一定的理论依据和生产指导. 相似文献