Phenolic contents,antioxidant activities and potential bioaccessibilities of industrial pomegranate nectar processing wastes

Antioxidant potential and bioaccessibility of co‐products from industrial pasteurised pomegranate nectar (PN) processing such as peel (PP), press cake (PC) and precipitate after clarification (PAC) in comparison with raw material (arils) and final products (CON and PN) were determined. Total phenolic (TPC), flavonoid (TFC), anthocyanin (TAC), tannin contents (TTC) and antioxidant activity (TAA) were determined besides identifying major phenolics and investigating in vitro bioaccessibility after gastrointestinal (GI) digestion. PP showed the highest values, except for TAC. Phenolics (12.7–43.0%) were found to be more stable than anthocyanins (0.6–2.1%) after in vitro GI digestion. PAC was found to be a better source for anthocyanins than CON and also showed higher phenolic bioaccessibility (28.8%) than PN (19.6%). PC and PAC possessed as much TPC, TFC, TTC and TAA levels as CON, with some exceptions. Therefore, these results indicated that not only PP but also PC and PAC should be valorised as a good source for phenolics and anthocyanins.     

Performance and Modeling of an Up-flow Anaerobic Sludge Blanket(UASB) Reactor for Treating High Salinity Wastewater from Heavy Oil Production

In this study,an up-flow anaerobic sludge blanket(UASB) reactor was applied to treat the high salinity wastewater from heavy oil production process.At a HRT of ≥24 h,the COD removal reached as high as 65.08% at an influent COD ranging from 350mg/L to 640mg/L.An average of 74.33% oil reduction was also achieved in the UASB reactor at an initial oil concentration between 112mg/L and 205mg/L.These results indicated that this heavy oil production related wastewater could be degraded efficiently in the UASB reactor.Granular sludge was formed in this reactor.In addition,two models,built on the back propagation neural network(BPNN) theory and linear regression techniques were developed for the simulation of the UASB system performance in the oily wastewater biodegradation.The average error of COD and oil removal was-0.65% and 0.84%,respectively.The results indicated that the models built on the BPNN theory were wellfitted to the detected data,and were able to simulate and predict the removal of COD and oil by the UASB reactor.     

How to report biogas production when monitoring small-scale digesters in field

The aim of this research was to evaluate the error originated when biogas production from field monitoring digesters, influenced by the diurnal temperature cycle, was normalized to standard conditions for pressure and temperature (273.15 K and 100 kPa) from local conditions. The biogas production data is often reported without indicating if done under local conditions, whether these conditions have been standardized and, if they have actually been standardized, the standard temperature and pressure is not indicated. In this research ambient and biogas temperature, as well as biogas production were monitored with a 30 min frequency during three consecutive days, in three different tubular digesters. Normalization was realized using the high frequency data collected as reference values, and also using daily biogas production with mean daily biogas, ambient and nearby meteorological station temperatures. The outcome of this research shows that normalization of biogas production can be obtained using daily biogas production and the daily mean ambient temperature with an overestimation by no more than 1.5%, in comparison to the normalization achieved by using high frequency data from biogas temperature and production. Using mean daily ambient temperature or mean daily biogas temperature results in the same overestimation, while using mean daily ambient temperature from a nearby airport weather station pushes the overestimation up to 2.7%. So, if ambient temperature and altitude is identified, biogas production reported in local conditions can be normalized.     

Stability of antioxidant peptides from duck meat after post‐mortem ageing

The stability of antioxidant peptides from aged duck meat during processing and simulated gastrointestinal digestion was investigated. The antioxidant peptides preserved a high stability in the presence of diverse NaCl or upon various time heating. The antioxidant activities were strengthened by the addition of 4–8% glucose or by heating at 100 °C, whereas they were lost under alkaline conditions. During in vitro digestion, the antioxidant activities increased with pepsin treatment but then decreased following trypsin digestion. Pepsin hydrolysed peptides into short fragments and results in the increased exposure of internal hydrophobic amino acids. With further treatment by trypsin, peptides can be hydrolysed completely and more free amino acids were released, leading to the decline in surface hydrophobicity. These variations might be responsible for the change in antioxidant activity during in vitro digestion. The antioxidant peptides from aged duck with high stability can be used as functional food ingredients to improve human health.     

Effects of intense magnetic field on digestion and settling performances of bauxite

The effects of magnetic field intensity, roasting temperature and roasting time on digestion rate and settling performance of bauxite with different iron contents were investigated systematically. The results indicate that such magnetic treatment can profoundly change the microstructure and digestion performance of bauxite. For the two samples carrying different iron contents, phase transformation of the aluminum oxide phase proceeds faster in the high iron bauxite than the low one. The optimal pretreatment conditions of low iron bauxite are roasting temperature 550 ℃ and magnetic field intensity 6 T, while for high iron bauxite are 500 ℃ and 9 T. The digestion rate of alumina can reach 95% and 92% at digestion temperature of 190 ℃ and 250 ℃. The settling performances of roasted ore by intense magnetic field after digestion are enhanced through pretreatment.     

中西药剂生产厂废水处理工程的技术改造

北京某制药厂废水包含中药、西药以及针剂废水,成分复杂且可生化性差,原废水处理工艺出水水质不能达标。通过分析,在充分利用原有构筑物的前提下,采用流离球技术对其进行技术改造,增设高效厌氧反应器、流离球生物反应池等工艺。结果表明,改造后的废水处理系统COD去除率达99%以上,且具有很强的抗冲击负荷能力,出水水质满足《北京市水污染物排放标准》(DB 11/307—2005)的一级B限值。     

湿法消化-氢化物原子荧光法测定植物提取物中镉的含量

探讨了应用原子荧光光法测定植物提取物中镉含量的方法。样品用硝酸+高氯酸混合液消化,在盐酸介质中,试样中的镉在镉专用2号试剂存在下,镉1号专用还原剂将二价镉还原成镉的挥发性组分,用AFS-8230原子荧光光度计测定。该法线性范围为0~60μg/L,相关系数r=0.9998,检出限为0.0024μg/L,相对标准偏差为1.36%,回收率为92.8%~96.1%。