Monolithically integrated CoP nanowire array: An on/off switch for effective on-demand hydrogen generation via hydrolysis of NaBH<Subscript>4</Subscript> and NH<Subscript>3</Subscript>BH<Subscript>3</Subscript>

The issues of hydrogen generation and storage have hindered the widespread use and commercialization of hydrogen fuel cell vehicles.It is thus highly attractive,but the design and development of highly active non-noble-metal catalysts for on-demand hydrogen release from alkaline NaBH4 solution under mild conditions remains a key challenge.Herein,we describe the use of CoP nanowire array integrated on a Ti mesh (CoP NA/Ti) as a three-dimensional (3D) monolithic catalyst for efficient hydrolytic dehydrogenation of NaBH4 in basic solutions.The CoP NA/Ti works as an on/off switch for on-demand hydrogen generation at a rate of 6,500 mL/(min.g) and a low activation energy of 41 kJ/mol.It is highly robust for repeated usage after recycling,without sacrificing catalytic performance.Remarkably,this catalyst also performs efficiently for the hydrolysis of NH3BH3.     

牛蒡寡糖免疫调节作用的研究

经口给予小鼠不同剂量的牛蒡寡糖20d后,与对照组相比能显著地提高小鼠抗体生成细胞数(低、中、高剂量组)、小鼠巨噬细胞吞噬指数(中剂量组)和小鼠脾脏、胸腺器官重量(低、中、高剂量组)。检测结果表明,牛蒡寡糖具有较强的调节小鼠体液免疫功能和调节小鼠巨噬细胞吞噬功能的作用。     

Concept for automated computer-aided identification and evaluation of potentially non-compliant food products traded via electronic commerce

The online marketplace for food products is continually expanding and all types of food and beverages can now be purchased over the internet. It is primarily the responsibility of the food business operator to ensure compliance with food safety law. However, the competent authorities are tasked with controlling the e-food sector as part of their regulatory duties to protect consumer health and to prevent fraud, regardless of the sales channel being used. For this purpose, a new software prototype concept was developed that automatically identifies and evaluates potentially non-compliant e-food products. The prototype was developed using a modular architecture comprising a research tool, an image analysis tool, and a monitoring tool. User-defined thresholds are applied to assess the reliability of the retrieved data. Results that are not deemed reliable enough can be reworked using a computer-aided evaluation interface. The research tool utilizes both internet search engines and customized search algorithms. A multi-stage filtering process is performed to limit the sites according to defined criteria (e.g. food product merchants only). The data acquisition module stores all matching data from webpages for later analysis and preservation of evidence. In another module, automatic recognition of a site's legal notice (impressum) is carried out for the respective vendor within whose online shop a potentially non-compliant food product is being offered. The image analysis tool performs logo recognition to enrich the text-based information of websites, thus providing additional visual information. The monitoring tool performs regular automated monitoring of e-food vendors, products and ingredients. The proof of principle of the prototype was achieved by conducting a web search for hazardous food products containing synephrine and caffeine. In total, 1242 product offerings on the internet for suspicious food products were identified among the 8683 search results. The software prototype has potential to enhance consumer protection and food safety with respect to e-foods.     

An analytical overview of the composition and characteristics of China's food safety standards

This paper discusses the framework of China's food safety standards and provides a brief overview of the problems and developmental characteristics of food safety in China. The composition and characteristics of China's food safety standards are revealed by an analysis of the changes in China's general food standards, an overview of the characteristics of the hygiene requirements in the production and operation process, and an introduction to food product and test method standards. In conclusion, Chinese food safety standards are still being improved, but they must also be effectively implemented and followed up in real time in order to continuously improve the quality of food and reduce food safety incidents. © 2024 Society of Chemical Industry.     

香蕉酸牛乳发酵工艺

将香蕉泥与牛奶调配接种乳酸菌发酵制成香蕉酸牛乳,研究不同工艺、不同稳定剂及配方的优化对香蕉酸牛乳成品品质的影响。确定香蕉牛乳的最佳发酵工艺：发酵剂4%、全脂乳4%、蔗糖6%、香蕉经微波处理30s、果肉10%、加入0.5% 柠檬酸和VC(2:1)、0.1% 明胶和0.1%CMC,在95℃水浴条件下杀菌5min,43℃温度条件下发酵5h,此条件下所得香蕉酸牛乳营养风味独特,感官评价最优。     

Effects of ε-Polylysine on Physicochemical Characteristics of Chilled Pork

The aim of this paper was to research effects of ε-polylysine (ε-PL) on physicochemical characteristics of chilled pork during storage. Chilled pork was treated with different concentrations of ε-PL. Sensory properties, total bacterial counts (TBC), pH, total volatile base nitrogen (TVB-N), metmyoglobin (MetMb) content, and α-thiobarbituric acid (TBA) of treated and control samples were analyzed periodically during refrigerated storage. Compared to control, significant reductions (p?<?0.05) for TBC, pH, TVB-N, and MetMb content of chilled pork treated with ε-PL during storage were found in this study. However, there were significant increments in sensory scores, and TBA almost did not change. TVB-N, pH, and log₁₀CFU/g showed a positive linear relationship among them. These results indicated that 1.25 % ε-PL could effectively inhibit the growth and reproduction of bacteria and enhance preservative effects of chilled pork. Thus, ε-PL has good potential to be a preservative and extends shelf life of chilled pork.     

仙人掌黄瓜复合饮料的研制

以“米邦塔”仙人掌和黄瓜为原料,进行仙人掌护色、原料配比、仙人掌黄瓜复合饮料稳定性和产品质量指标实验,研制出复合饮料。采用正交试验探索出仙人掌黄瓜复合饮料的最佳工艺配方：仙人掌汁15%,黄瓜汁30%,白砂糖9%;仙人掌汁较好的护色剂为0.6g/L VC ＋ 0.02g/L Na2SO3、热烫时间3min、护色时间0.5h,复合稳定剂为同时添加总量各为0.1% 的耐酸CMC-Na 和卡拉胶。     

桃汁贮藏期间的品质变化研究

为探讨桃汁贮藏期间品质的变化,将鲜桃汁灭菌后分别贮藏在4℃、25℃和37℃下,检测并分析桃汁贮藏期间的理化指标、营养成分和香气成分的变化。发现在4℃、25℃和37℃下,桃汁的褐变度分别增加了0.14、0.33和0.56;总糖分别降解了49.06%、53.59%和57.19%;维生素C分别降解了46.27%、43.05%和51.06%;蛋白质分别降解了31.82%、57.14%和64.00%;总酸含量变化很小。桃汁在贮藏过程中,贮藏温度和贮藏时间对褐变度、总糖、维生素C、蛋白质、总酚、果胶等含量的变化均有极显著影响(p0.01)。在对桃汁贮藏期间香气成分变化的研究中,共鉴定出35种香气成分。新鲜桃汁具有较好的香气,其特征香气十一烷-4-内酯达到1.25%,5-癸内酯达到4.45%。贮藏40 d后,4℃下鉴定出的香气成分占总质量分数的79.90%,25℃下鉴定出的香气成分占总质量分数的60.14%,37℃下鉴定出的香气成分占总质量分数的54.59%。因此,低温贮藏有助于桃汁品质地保持。     

气相离子迁移谱结合化学计量法快速鉴别不同产地连翘

分析不同产地芋头挥发性有机化合物组成差异,并构建芋头产地溯源的可视化指纹图谱。采用气相离子迁移谱法对不同产地芋头的挥发性物质进行测定,结合主成分分析（PCA）实现样品产地的快速区分,进一步筛选芋头中差异挥发性物质。结果表明,在不同产地芋头中,共检测到45个信号峰,鉴定出26种化合物,包括单体和部分化合物的二聚体。主成分分析将芋头分为3类,其中,靖江香沙芋和奉化芋头的挥发性物质较为相似,而与荔浦芋头、沙沟芋头差别很大。异丙醇、2-甲基-乙酸丁酯、辛酸甲酯是区别不同芋头的特征标记物。该方法直观、快速,为地方特色芋头的区分提供了新方法和技术支持。