浙江食品添加剂与配料行业现状、问题和对策

没有食品添加剂就没有食品工业。食品添加剂直接关系食品品质和安全,关系国家政治稳定和社会发展。食品添加剂不仅拉动了食品工业和农业的发展,而且对促进饮食结构改善负有重要使命。浙江是食品添加剂和配料大省,从浙江省食品添加剂与配料行业现状出发,分析了其中存在的问题,提出了相应的对策,欲为广大食品添加剂产业的从业人员提供有益的参考。     

预制装配式基础及其在通信基站中的应用

预制装配式基础在通信基站中是一种比较新颖的应用方式,可以达到快速建站的目的,并可有效解决扰民等问题。本文介绍了预制装配式基础的设计由来、结构构造、适用范围、应用方向,并列举了工程应用的实例。     

京杭运河杭州段水质模型研究

以京杭运河杭州段为对象,研究主要水污染超标因子氨氮的浓度预测方法.选取2007年6月2～10日运河实测水质变化过程,根据干流各节点的初始浓度和各支流的浓度,结合水位流量自动监测数据,分别用简化水库模型和有限差分法预测运河干流各节点的氨氮浓度,并与实测值进行比较分析.简化水库模型和有限差分法应用于该次水体氨氮浓度计算中,两者的误差均在5%以内,对运河水质预测均有一定的代表性.     

Type-2 fuzzy mathematical modeling and analysis of the dynamical behaviors of complex ecosystems

It is very complex to model, study and analyze the dynamical behavior of the complex ecosystems. Many ecological theoretical problems are based on niche. The niche one species occupies and the relation between niches of different species will directly influence the species’ dynamical behavior. The discussion of niche has been very important to an ecosystem. Fuzzy set theory gave a new creative method to form the niche of a species. Based on broadband effect inherent in membership function of type-2 fuzzy set, the dynamic niche model of fuzzy niche theory is proposed. It is applied to explain the relationship between niches’ separating degree and competition of species and study the dynamical behavior emerging in the competition bio-system. It also analyses the case of the biological synergism in a simulate Lotka–Volterra competition bio-system based on niches.     

Characterization of polystyrene-binding peptides (PS-tags) for site-specific immobilization of proteins

In this study, we characterized polystyrene-binding peptides (PS-tags) that possess a specific binding affinity for hydrophilic polystyrene (phi-PS) plates. Both the FITC-labeled PS19-1 (RAFIASRRIKRP) and PS19-6 (RIIIRRIRR) peptides showed strong binding affinity for commercially available hydrophilic, but not hydrophobic, PS plates in the presence of the non-ionic surfactant Tween 20. The dissociation constants (K_d) of the PS19-1 and PS19-6 peptides for the hydrophilic PS-A plate were 169 and 86 nM, respectively, and the K_d of both peptides increased with the concentration of NaCl or urea. Based on adsorption yield and residual activity of glutathione S-transferase (GST) after fusion with the PS19-6 peptide or its variants, it was found that the basic amino acid in the PS-tags, i.e., Arg was essential for the strong binding affinity of PS-tags in both the peptide and peptide-fused protein forms The aliphatic amino acids in PS19-6 and PS19-6L, such as Ile or Leu, were also effective. Thus, a series of PS-tags that possess this unusual feature, especially the peptides PS19-6 (RIIIRRIRR) and PS19-6L (RLLLRRLRR), are potential candidate affinity peptide tags for site-specific immobilization of proteins onto hydrophilic PS plates, which show potential as solid supports for protein-based biochips.     

映秀湾电站地下厂房顶拱钢吊顶天棚稳定分析

本文以空间刚架模型及杆系有限元法用空间刚架的静、动力分析理论对映秀湾地下厂房顶拱钢吊顶天棚进行了静、动力分析，并提出了稳定分析方法，所得结果与实测结果较为一致。为今后对该类工程问题的稳定计算提供了一个可供参考的工程实例。     

一种降低OFDM信号峰平功率比的新方案

提出一种基于子块幅度加权处理降低正交频分复用（OFDM）信号峰值平均功率比的新方法。在确保性能满足系统需求的条件下,通过预设优化处理门限进行循环移位优化,从而大大降低了算法的复杂度。研究与仿真结果表明,基于子块幅度加权的循环移位优化方法可以有效降低OFDM信号峰值平均功率比,且具有复杂度低、处理灵活、无需边信息等优点。     

Preparation of closed-pore MgO-MgFe2O4 aggregates with low thermal conductivity and high mechanical properties

MgO-MgFe₂O₄ refractory aggregates with high closed porosity were fabricated using MgO agglomerates and Mg(OH)₂ with introducing Fe₂O₃ additive. The evolutions of pores and microstructure and their relationship with the properties of the specimens were studied. The addition of Fe₂O₃ obviously promoted the MgO grain growth and conversion of large open pores into small closed pores, attributing to the formation of cationic vacancies and intergranular MgFe₂O₄ bonding phase. Owing to the presence of closed pores and networks of intergranular MgFe₂O₄, both thermal insulation and strength were enhanced significantly. Besides, the formed closed pores and MgFe₂O₄ phase could accommodate thermal stress and induce transgranular fracture and crack deflection, therefore effectively improving the thermal shock resistance. The specimen with 15 wt% Fe₂O₃ showed a apparent/closed porosity of 0.7%/10.1%, median pore diameter of 4.37 µm, thermal conductivity of 9.3 W/(m·K) (500 °C), flexural strength of 143.5 MPa, and residual flexural strength of 24.1 MPa after thermal shock.     

框架锚杆在山区边坡加固中的应用

持续的强降雨使得架空线路的基础边坡发生大规模边坡溜坡事故,给线路运行带来安全隐患。采用框架锚杆加固、框架内挂网喷浆或植被防护、三维网植草、加强截排水等一系列综合措施对边坡进行加固处理,取得良好的加固效果。主要通过现场岩土锚杆的拉拔试验以验证框架锚杆设计参数的合理性,结果表明框架锚杆对山区架空线路的边坡加固具有良好的经济...     

菌菇营养茶有效成分溶出条件优化研究

菌菇营养茶兼有菇和茶的营养保健功效,即可作茶单独饮用,也可作酱卤制品的营养调味料。本文研究以茶菇配比、冲泡固液比和时间为因素,多糖含量为指标,采用响应面法优化菌菇营养茶有效成分溶出的条件。结果表明:茶与菇的最佳配比为3:1,用32倍的水冲泡,冲泡5min可最大限度地保证其功效成分。