新型抗冻太阳能冷管的试验研究

根据固体吸附制冷原理,利用太阳光作为热源,采用活性炭-甲醇作为工质对,首次研制成了抗冻型太阳能冷管,该冷管制冷温度可以达到-5℃以下,单支抗冻型太阳能冷管制冷量可以达到100 kJ,制冷系数COP达到0.11.     

移动式空调控温储粮试验

华南地区长期处在高温高湿天气,低温时间较短,对储粮品质的稳定性和安全极为不利。在高大平房仓利用移动式空调,调控仓内粮面到拱板之间的空间温度,减轻仓内温度对粮温的影响,对延缓粮堆粮温上升速度,延缓粮食品质劣变起着积极作用。     

Evaluation of different extenders for the cold storage of meagre (Argyrosomus regius) semen

Meagre (Argyrosomus regius) is considered a potential candidate for aquaculture diversification in southern Europe. The main objective of this experiment was to develop a cold storage protocol for meagre semen to facilitate artificial reproduction techniques. Three extenders (non‐activating medium, 0.9% NaCl, and 0.9% NaCl with glycine and glucose) in three different sperm:extender dilutions (1:4, 1:9 and 1:19) were tested in a full factorial design. The quality parameters assessed along the storage time were the sperm motility, viable sperm percentage, adenosine triphosphate (ATP) content, and bacterial growth. The 0.9% NaCl and 0.9% NaCl with glycine and glucose extenders and the 1:4 and 1:9 dilutions maintained a higher sperm motility and a higher sperm linearity for a longer period time. Sperm viability was maintained at a higher value over a longer period with the 0.9% NaCl and 0.9% NaCl with glycine and glucose extenders. Sperm motility and viability appeared to be the main parameters showing the loss of semen quality during cold storage. Meagre semen demonstrated an ability to be stored for up to 10 days at 4°C when using 0.9% NaCl in a 1:4 dilution. These results contribute to a better understanding of the causes of fish semen quality deterioration during cold storage.     

Dynamics of Bacterial Communities in Postharvested Eastern Oyster (Crassostrea virginica) Maintained Under Refrigeration

The selective effect that refrigeration exerts on the autochthonous microbiota of the eastern oyster was investigated using culture-independent methods. Oysters from two different locations along the Gulf Coast of Mexico were analyzed concurrently during 2-week refrigeration. Ribosomal intergenic sequence analysis (RISA) generated complex bacterial community fingerprints that provided a strong association between RISA-defined clusters and sample date. Denaturing gradient gel electrophoresis (DGGE) profiles obtained with universal primers did not reflect any association based on date or geographic origin of the samples. During the storage period, Vibrio parahaemolyticus was replaced, at least in overall abundance, with other nonpathogenic Vibrio species better adapted to cold temperatures. This study shows that refrigeration itself does not limit the growth of the bacterial community nor reduces its richness.     

关于机械制冷系统在猕猴桃贮藏保鲜当中的应用推广

文章通过对机械制冷系统在猕猴桃贮藏保鲜当中运用的论述,提出了机械制冷系统在贮藏保鲜当中的一些作用和存在问题以及怎样进行正确使用与维修,对合理、科学、使用猕猴桃制冷机械有指导作用.     

吸附式制冷在船舶中央空调系统中的应用

以实际营运船舶额定工况下空调负荷为基准,首先从热平衡角度,分析利用柴油机缸套冷却水余热制冷的可行性.其次以特定船舶中央空调所需冷量为标准,对吸附式制冷系统的核心部件吸附床进行初步设计.最后对吸附单元进行传热传质数值计算,分析吸附床厚度、缸套水流速、硅胶填充密度及硅胶比热容对吸附床传热性能的影响.     

南方葡萄预冷冷藏保鲜技术研究与推广

葡萄产后保鲜与管理是葡萄生产的重要节,也是提高葡萄生产经济效益的重要技术措施。通过对湖南产红地球葡萄品种的冷藏保鲜试验表明,适当的贮藏方法,南方葡萄亦可以保存相当长的时间。但南方普遍采用的机械冷库冷藏方式,冷藏前的库体消毒适宜SO2熏蒸法,而对葡萄消毒宜采用亚硫酸盐消毒。     

维生素C对藏西北绒山羊精液冷藏效果及 其全基因组DNA甲基化的影响

[目的]研究维生素C对4℃保存藏西北绒山羊精液效果及其全基因组DNA甲基化的影响,为高效利用藏西北绒山羊种公羊精液及推广其人工授精技术打下基础.[方法]假阴道人工采集藏西北绒山羊种公羊新鲜精液,用维生素B12进行4倍稀释后添加不同浓度的维生素C(0、2.0、4.0、6.0、8.0、10.0和12.0 mg/mL),4℃保存24 h,观察统计其精子活力、精子顶体完整率和质膜完整率,并通过实时荧光定量PCR检测精子全基因组DNA甲基化的情况.[结果]藏西北绒山羊精液4℃保存24 h后,以添加8.0 mg/mL维生素C的效果最佳,对应的精子活力、精子顶体完整率和质膜完整率分别为(73.41±0.47)%、(58.89±0.88)%和(68.76±0.81)%,3个指标均极显著高于未添加维生素C的空白对照组(P<0.01).添加8.0 mg/mL维生素C的藏西北绒山羊精子全基因组DNA甲基化水平与新鲜精液的接近,均显著低于未添加维生素C的冷藏精液(P<0.05).[结论]原精液中添加2.0 mg/mL维生素C可降低4℃保存藏西北绒山羊精液的全基因组DNA甲基化异常水平,提高藏西北绒山羊精液冷藏效果.     

~（60）Co和速冻对银杏种胚及氢氰酸含量的影响

银杏种实于８月受精，受精后受精卵形成胚。采收后，在胚形成初期，用０．１７，０．３９，１．５５。３．１０Ｃ／ｋｇ的~（６０）Ｃｏ分别进行照射和－３０℃，－５０℃速冻处理，两者的种仁中氢氰酸含量均显著或极显著低于对照，且各处理不同水平间的种仁氢氰酸含量达到显著或极显著差异水平。高剂量的~（６０）Ｃｏ辐射，能明显抑制银杏种子发芽，降低发芽速度，缩短发芽长度。     

不同冻藏温度对新疆高白鲑鱼肉的品质变化

【目的】 研究新疆高白鲑鱼肉在冷藏(4℃)、冰温(0℃)和冷冻(-18℃)3个冻藏条件下理化品质、感官评价及微生物的变化。【方法】 通过对理化(pH值、TVB-N值、TBA值、色泽和质构特性)、感官评价及微生物指标的测定,研究新疆高白鲑鱼肉在冷藏(4℃)、冰温(0℃)和冷冻(-18℃)过程中的品质变化,分析高白鲑在不同冻藏温度条件下的品质变化规律。【结果】 不同冻藏温度条件下的高白鲑鱼肉,伴随着贮藏时间的延长,其品质指标的变化规律均不同。pH值呈明显的先快速降低再缓慢升高的趋势;TVB-N值和TBA值均随贮藏时间的增加而逐渐升高;色泽饱和度与各项质构特性指标同贮藏时间呈现显著的负相关;感官评价得分逐渐降低;而菌落总数则呈持续上升趋势。其中,冷藏(4℃)的各项指标变化速率最快,冷冻(-18℃)的品质变化速率最慢且差异最小;冷藏(4℃)6 d和冰温(0℃)10 d的高白鲑鱼肉明显腐败且伴有异味,菌落总数值为5.68和7.86 lgcfu/g,已超过加工食用的最高安全限量标准值;冷冻(-18℃)20 d仍为可接受收范围,至贮藏结束菌落总数的测定结果为4.52 lgcfu/g。【结论】 与冷藏(4℃)和冰温(0℃)相比,冷冻(-18 ℃)贮藏条件可有效抑制高白鲑鱼肉酸败和腐败现象的发生,贮藏温度对高白鲑鱼肉整体色泽饱和度的变化影响较大,低温冷冻贮藏对减缓高白鲑鱼肉的固有色泽品质劣化作用明显。