Advances in the in vitro digestion and fermentation of polysaccharides

In vitro digestion models are widely used to study the structural changes, digestion and release of food components under simulated gastrointestinal conditions. As compared to the in vivo digestion tests, the in vitro digestion reflects the digestion and utilisation of food after ingestion and has the advantages of being time consuming, inexpensive, reproducible and free from moral and ethical restrictions. This study reviewed the current research studies on the in vitro simulated digestion of polysaccharides conducted in the last 5 years and focused on the oral, gastric and intestinal digestion models, with the aim of providing a basis for the further testing of changes in the content, structure and active ingredients of polysaccharides before and after digestion.     

水文序列相依变异识别的RIC定阶准则——以自回归模型为例

水文过程相依性是水文变异的主要表现形式之一,应用自回归模型对其进行拟合时合理确定模型阶数是一个难点问题。本文在分析AIC和BIC准则的基础上,提出了一种以原序列与其相依成分的相关系数作为拟合度指标,同时借用信息熵形式的函数式,作为模型不确定性度量指标的自回归模型定阶准则(简称RIC准则)。以AR(1)、AR(2)、AR(3)和AR(4)模型为例进行统计试验,将不同序列长度下该准则的定阶准确率与其他定阶准则进行比较,试验结果表明,RIC准则对于上述模型均具有较好的适应性,且定阶准确率远高于AIC准则,其中对于前三阶模型RIC准则优于BIC准则,但四阶模型略低于BIC准则。RIC准则的优势是可以同时满足模型定阶、相依程度分级与模型检验的需求,将其应用于实测水文序列分析,结果显示,该准则能较准确地识别自回归模型的阶数,且符合提出的"相依有变异而残差无变异的最小阶数"的检验标准。     

Constructive Sets in Computable Sets

The original interpretation of the constructive set theory CZF in Martin-Loef‘s type theory uses the‘extensional identity types’.It is generally believed that these‘types’do not belong to type theory.In this paper it will be shown that the interpretation goes through without identity types.This paper will also show that the interpretation can be given in an intensional type theory.This reflects the computational nature of the interpretation.This computational aspect is reinforced by an ω-Set moel of CZF.     

大庆油田葡深1井射孔及测试

葡深1井完钻井深5500m，井温高达200℃以上，射孔、测试施工难度大。经过针对性的射孔测试设计和模拟试验，成功地完成了二层射孔及测试，射孔弹发射率100％，获取了合格的地层测试资料，为该地区下步深层勘探布署提供了科学依据。     

Correction to: Parallel Single-Pixel Imaging: A General Method for Direct–Global Separation and 3D Shape Reconstruction Under Strong Global Illumination

International Journal of Computer Vision - In the original publication of the article, the name of the last author should be Yang Xu, instead of Xu Yang. “Xu” is the family name, and...     

海绵城市建设理念在无为某城区改造中的应用

以无为某城区为例,通过分析当地气象、水文自然条件和建筑类型,结合低影响开发(LID)理念,灵活运用"渗、滞、蓄、净、用、排"六字方针,合理布局下沉式绿地、绿色屋顶、生物滞留网格、透水铺装等海绵设施,构建雨水下渗、蓄滞、传输系统,并建立暴雨洪水管理模型(SWMM),重现期取3年,对改造前研究区域和增加4种低影响开发措施的改造后研究区域的雨量控制进行评价.结果显示,LID设施削减了雨洪峰值,减小了径流量,城区内涝问题得到有效控制,蓄滞、吸纳雨水能力显著提升,生态环境明显改善;改造后研究区域的年径流总量控制率比目标年径流总量控制率提高了2％,满足控制性指标.     

硅质隔热耐火砖制作工艺及质量控制程序和方法

为实现窑炉的长寿、节能、低耗,硅质隔热耐火砖的质量起着至关重要的作用。本文介绍了硅质隔热耐火砖的制作工艺、过程控制及质量控制程序和方法。结果表明：采用该质量控制方法生产的硅质隔热耐火砖质量优良,经久耐用,取得了良好的效果。     

A high propylene productivity over B2O3/SiO2@honeycomb cordierite catalyst for oxidative dehydrogenation of propane

Boron-based metal-free catalysts for oxidative dehydrogenation of propane (ODHP) have drawn great attention in both academia and industry due to their impressive activity and olefin selectivity. Herein, the SiO₂ and B₂O₃ sequentially coated honeycomb cordierite catalyst is designed by a two-step wash-coat method with different B₂O₃ loadings (0.1%-10%) and calcination temperatures (600, 700, 800 ℃). SiO₂ obtained by TEOS hydrolysis acts as a media layer to bridge the cordierite substrate and boron oxide via abundant Si-OH groups. The welldeveloped straight channels of honeycomb cordierite make it possible to carry out the reactor under high gas hourly space velocity (GHSV) and the thin wash-coated B₂O₃ layer can effectively facilitate the pore diffusion on the catalyst. The prepared B₂O₃/SiO₂@HC monolithic catalyst exhibits good catalytic performance at low boron oxide loading and achieves excellent propylene selectivity (86.0%), olefin selectivity (97.6%, propylene and ethylene) and negligible CO₂ (0.1%) at 16.9% propane conversion under high GHSV of 345,600 ml·(g B₂O₃)^-1·h^-1, leading to a high propylene space time yield of 15.7 g C₃H₆·(g B₂O₃)^-1·h^-1 by suppressing the overoxidation. The obtained results strongly indicate that the boron-based monolithic catalyst can be properly fabricated to warrant the high activity and high throughput with its high gas/surface ratio and straight channels.     

超快平面显微成像技术

快速成像技术在很多领域都有着重要的应用,本文基于超短光脉冲的时-空-频映射原理,提出并实现了一种超快平面显微成像技术。利用色散傅里叶变换及空间色散器件把光脉冲的宽带频谱信息分别映射到时域和空域,利用高速光电探测器进行串行单像素成像,最终获得了帧速率为20.9 MHz,空间分辨率为22 μm和55 μm的一维及二维平面成像系统。在实验中用标准的分辨率目标板验证了成像效果。该技术为超快成像提供了一种有效手段,并将应用于高速平面检测等多个领域。     

A high propylene productivity over B2O3/SiO2@honeycomb cordierite catalyst for oxidative dehydrogenation of propane

Boron-based metal-free catalysts for oxidative dehydrogenation of propane (ODHP) have drawn great attention in both academia and industry due to their impressive activity and olefin selectivity. Herein, the SiO₂ and B₂O₃ sequentially coated honeycomb cordierite catalyst is designed by a two-step wash-coat method with different B₂O₃ loadings (0.1%–10%) and calcination temperatures (600, 700, 800 °C). SiO₂ obtained by TEOS hydrolysis acts as a media layer to bridge the cordierite substrate and boron oxide via abundant SiOH groups. The well-developed straight channels of honeycomb cordierite make it possible to carry out the reactor under high gas hourly space velocity (GHSV) and the thin wash-coated B₂O₃ layer can effectively facilitate the pore diffusion on the catalyst. The prepared B₂O₃/SiO₂@HC monolithic catalyst exhibits good catalytic performance at low boron oxide loading and achieves excellent propylene selectivity (86.0%), olefin selectivity (97.6%, propylene and ethylene) and negligible CO₂ (0.1%) at 16.9% propane conversion under high GHSV of 345,600 ml·(g B₂O₃)⁻¹·h⁻¹, leading to a high propylene space time yield of 15.7 g C₃H₆·(g B₂O₃)⁻¹·h⁻¹ by suppressing the overoxidation. The obtained results strongly indicate that the boron-based monolithic catalyst can be properly fabricated to warrant the high activity and high throughput with its high gas/surface ratio and straight channels.