粉条加工中添加石蜡的检测技术研究

【目的】探讨粉条加工过程中非法添加石蜡的测定方法,为食品监管提供保障。【方法】先以石蜡成品摸索石蜡测定的气相色谱质谱条件,再以石蜡成分C18H38和C24H50进行回收率和相对标准偏差试验。【结果】不同预处理方法中,超声萃取处理的C18H38和C24H50在粉条中的萃取回收率最高,分别为93.5%和91.0%;20min超声时间萃取粉条中烷烃成分较为适宜;所建立的粉条中石蜡含量测定方法的相对标准偏差为3.6～4.8,样品回收率均大于90.0%,达到定量检测要求。【结论】所建立的石蜡检测方法操作简单,测定结果准确可靠,可用于粉条中石蜡成分的定性及定量测定。     

微藻水热液化有机相最佳回收工艺研究

以微拟球藻为原料,研究微藻水热液化过程中多种参数对水热液化后有机物回收率的影响,包括温度、时间、溶剂比和pH等,从而获得微藻水热液化后有机物的最佳回收工艺条件。结果显示,在室温下进行有机相回收,保证回收溶剂比为20∶1(溶剂/水相不溶物;v/wt)、停留时间为10min、回收pH7,即可达到最佳回收效果。最佳条件下水热液化有机相的回收率为34%左右,且不同的回收温度和pH值对回收的有机相组分均会产生影响。     

Glycine max and Glycine soja are capable of cold acclimation

Soybean has been considered a cold intolerant species; based largely upon seed germination and soil emergent evaluations. This study reports a distinct acquisition of cold tolerance, in seedlings, following short acclimation periods. Diversity in cold responses was assessed in eight cultivars of Glycine max and six accessions of G. soja. All varieties of soybean significantly increased in freezing tolerance following acclimation. This study indicates soybean seedlings are indeed capable of sensing cold and acquiring cold tolerance. Germination rates after cold imbibition were negatively correlated with maturity group, but positively correlated with cold acclimation potential in G. soja. Seed fatty acid composition was varied between the species, with Glycine soja accessions containing about 2‐times more linolenic acid (18:3) than G. max. Furthermore, high levels of linoleic acid (18:2) in seeds were positively correlated with germination rates following cold imbibition in G. soja only. We suggest that domestication has not impacted the overall ability of soybean to cold acclimate at the seedling stage and that there is little variation within the domesticated species for ability to cold acclimate. Thus, this brief comparative study reduces the enthusiasm for the “wild” species as an additional source of genetic diversity for cold tolerance.     

海洋灾害对渔业资源管理的影响及其对策

近年来,恶性捕捞严重,海洋渔业资源管理模式落后。同时,人类过度开发利用以及不可抗因素时有发生,使得海洋生态系统遭到破坏,渔业资源管理也面临着新的问题。对我国渔业资源管理现状以及非常态下渔业资源的恢复与开发利用等方面进行了综述,对非常态下渔业资源管理中存在的问题进行了阐述,并提出了对应的管理措施,最后对非常态下渔业资源管理制度发展建设进行了展望。     

屋面防水的施工要点与整改措施

防水工程一直是建筑施工中难以控制的分项,防水层关系到日后的质量问题,如渗水势必会对房屋的适用性、耐久性造成影响.防水层的试水试验相当重要,也做为检验防水层施工质量的依据,今后施工防水层一定要重视蓄水试验,按照设计及技术方案做好防水层的施工.     

松茸多糖对缓解运动员有氧运动疲劳恢复应用研究

通过分析松茸多糖对有氧运动所产生的一系列良好效果,进行松茸多糖对运动员疲劳恢复的相关研究,松茸多糖主要涉及到运动员运动过程当中,其机体所产生的血清尿素(BU)含量、血清丙二醛(MDA)含量、血清肌酸激酶(CK)、血清超氧化物歧化酶(SOD)以及谷胱甘肽过氧化物酶(GSH-PX)活性的变化。相关研究结果表明,松茸多糖能够对此起到良好的修复作用,有效抑制运动过后所产生的骨骼肌损伤,增强运动员机体抗氧化能力,从而达到恢复疲劳的作用。     

三峡大学校园垃圾分类回收现状及回收机制的建立探讨

指出了垃圾分类回收具有重要的意义，有利于资源节约型和环境友好型社会的建设，有利于循环经济的可持续发展。分析了校园垃圾分类回收现状，对建立校园分类回收机制进行了探讨。     

Recovery of sperms bearing X chromosomes with different concentrations of magnetic nanoparticles in ram

Pre-conceptual sex selection is still a highly debatable process whereby X and Y chromosome bearing spermatozoa are isolated before oocyte fertilization. Recently, magnetic nanoparticles (MNP) have been used to determine X and Y chromosomes bearing spermatozoa as a result of searching for a cheap, highly efficient method using non-toxic materials. This study aimed to recover the sperm bearing X chromosomes in ram with different concentrations of MNP and then evaluate the success of this method using polymerase chain reaction (PCR). Ram sperms were divided into four groups, treated with 0 (control), 50, 100 and 200 μg/ml MNP, respectively. MNP was used to restore sperm cells bearing X chromosomes. Upon recovery, the PCR was performed to identify the X and Y sperms, Methyl ThiazoleTetrazolium (MTT), to assess MNP toxicity and sperm viability and acridine orange (AO) to evaluate sperm DNA integrity. The results of PCR revealed that the treatment of spermatozoa- bearing X chromosomes with 50 μg/ml MNP had the highest effects on the recovery of X sperm rather than the other concentrations of MNP. However, the concentrations of MNP did not have any toxic effects on spermatozoa, sperm viability and, DNA integrity, but the high concentration of MNP (200 μg/ml) significantly reduced DNA integrity. According to MTT and AO results, the concentrations of MNP used in this study had no toxic effects on spermatozoa and did not reduce the sperm viability and DNA integrity, except that 200 μg/ml MNP significantly reduced DNA integrity.