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101.
102.
高性能纤维是具有特殊的物理化学结构、性能和用途,或具有特殊功能的化学纤维。简述了高性能纤维的基本分类,并介绍了芳纶纤维、PBO纤维、碳纤维、玻璃纤维四种高性能纤维的性能及应用,并分析了高性能纤维今后的发展趋势。 相似文献
103.
针对纸浆浓度控制系统具有大纯滞后和模型不确定的特性,提出将神经元PID控制和Smith预估控制相结合的控制策略。该控制系统既具有Smith预估补偿控制的优点又有神经元自学习、自适应的能力。仿真实验结果表明该方法可以提高系统的控制品质,证实了这种方法的可行性。 相似文献
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This study investigates the co-digestion of poultry manure (PM) with sugar beet pulp residues (SBPR) obtained from saccharification and dewatering of sugar beet pulp. The laboratory-scale experiments were conducted under batch and semi-continuous conditions at mesophilic temperatures (35 °C). Batch tests gave specific biogas and methane yields of 590 dm3/kgVSfed and 423 dm3CH4/kgVSfed, respectively for SBPR, whereas the corresponding values for PM were 434 dm3/kgVSfed and 300 dm3CH4/kgVSfed. The co-digestion of PM with SBPR was found to increase biogas and methane yields compared to the manure alone. In semi-continuous reactor experiments, the highest methane yield of 346 dm3 CH4/kgVSfed was achieved for the mixture containing poultry manure with 50% SBPR (weight basis) and a solids retention time (SRT) of 20 days. However, when poultry manure was digested as a sole feedstock, the biogas production was inhibited by ammonia, whereas the co-digestion of PM with 25% SBPR was slightly affected by volatile fatty acids, which concentrations exceeded 4000 g/m3. 相似文献
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Jon Luzuriaga Yurena Polo Oier Pastor-Alonso Beatriz Pardo-Rodríguez Aitor Larraaga Fernando Unda Jose-Ramon Sarasua Jose Ramon Pineda Gaskon Ibarretxe 《International journal of molecular sciences》2021,22(7)
Human dental pulp stem cells (hDPSCs) are some of the most promising stem cell types for regenerative therapies given their ability to grow in the absence of serum and their realistic possibility to be used in autologous grafts. In this review, we describe the particular advantages of hDPSCs for neuroregenerative cell therapies. We thoroughly discuss the knowledge about their embryonic origin and characteristics of their postnatal niche, as well as the current status of cell culture protocols to maximize their multilineage differentiation potential, highlighting some common issues when assessing neuronal differentiation fates of hDPSCs. We also review the recent progress on neuroprotective and immunomodulatory capacity of hDPSCs and their secreted extracellular vesicles, as well as their combination with scaffold materials to improve their functional integration on the injured central nervous system (CNS) and peripheral nervous system (PNS). Finally, we offer some perspectives on the current and possible future applications of hDPSCs in neuroregenerative cell therapies. 相似文献
109.
Jingjing Huang Siyuan Wang LiYun Zhang Jihong Wu Zenghui Xu Xiaojun Liao Yanling Hao Yan Zhang 《International Journal of Food Science & Technology》2012,47(12):2620-2626
The inactivation of bacteria naturally present in strawberry pulp was investigated after high hydrostatic pressure (HHP) treatment at pressure levels up to 600 MPa at 25 °C for 5 ~ 25 min. Five strains of pressure‐resistant bacteria designated as A, B, C, D and E were isolated and identified. The five strains were gram‐positive, spore‐forming, rods or rod in chains. Growth of the strains was observed at 30 ~ 45 °C, and strain B also grew well at 55 °C. They could produce acid from glucose and were catalase‐positive. Analysis of 16S rRNA gene sequences showed that the five strains belonged to the genus Bacillus. Strain A and D exhibited the greatest 16S rRNA gene sequence similarity of 99% with B. licheniformis and B. firmus, respectively. By combination of phenotypic characteristics and 16S rRNA gene sequences, strain C was B. mycoides and E was B. pumilus. On the basis of physiological and biochemical characteristics, gyrB gene sequences analysis and whole‐cell fatty acids analysis, strain B was B. amyloliquefaciens. Further studies showed that strain B (B. amyloliquefaciens) exhibited the highest pressure resistance, and it was reduced by 4.62‐log after treatment at 600 MPa for 25 min at 25 °C as the most effective observed inactivation. 相似文献
110.
《Measurement》2016
This study measured the effect of sugar beet pulp (SBP) and maleated polyethylene (MAPE) concentrations on the properties of low density polyethylene (LDPE) composites. SBP concentration has significantly increased density, thickness swelling (TSW), water absorption (WA), flexural strength (FS), tensile modulus (TM) and flexural modulus (FM) of composites while reducing tensile strength (TS), elongation at break (EatB) and impact strength (IS). Presence of MAPE has improved TSW, WA, TS, FS, TM and FM. However, EatB and IS were slightly worsened by MAPE use. Composites showed two main decomposition peaks; one coming from SBP (360–368 °C) and the second one from LDPE degradation (484–490 °C). SEM images showed improved dispersion of SBP. The composites has provided less than 2% weight loss and classified as ‘very durable material’ against white-rot and brown-rot fungi attack. Through this study, potential utilization of SBP in LDPE matrix was demonstrated. 相似文献