臭氧对‘鸭梨’等3种梨果保鲜效果的影响

以‘鸭梨’、‘雪花梨’和‘黄冠梨’为试材,研究了不同浓度的臭氧对梨果品质的影响.结果表明,臭氧处理使‘鸭梨’和‘雪花梨’贮藏期变短,臭氧浓度越大,‘鸭梨’硬度、可溶性固形物、可滴定酸含量下降得越快,果面软化现象发生得越早;臭氧处理延缓了‘雪花梨’可溶性固形物、可滴定酸含量的下降,但使其果点变黑,浓度越大,发生时间越早.臭氧处理延缓了‘黄冠梨’硬度、可溶性固形物及可滴定酸含量的下降,降低了鸡爪病、黑心病的发病率及烂果率,60 mg/m3臭氧处理的‘黄冠梨’贮藏保鲜效果最佳.     

大蒜提取液对番茄的保鲜效果

为了延长番茄的贮藏时间,减少因腐烂变质造成的损失,以鲜番茄为原料,用不同浓度料液比大蒜提取液对番茄进行浸泡处理。以鲜番茄贮藏期的总糖含量、失重率、维生素 C 含量、腐烂指数和感官品质为测定指标,研究不同大蒜提取液对番茄的保鲜效果。结果表明：不同料液比的大蒜提取液均有保鲜作用,其保鲜效果由大到小顺序为1∶6＞1∶10＞1∶14＞1∶18。番茄在大蒜提取液料液比1∶6的条件下保鲜效果最好,可保鲜15 d。对照在第12天时失去食用价值,大蒜提取液料液比1∶6处理的番茄在12 d 时,总糖含量为9．5％,维生素 C 含量为77 mg/100g,比对照组分别高3．9％和16 mg/100g;失重率达2．6％,腐烂指数为9％,比对照组分别低2．8％和33％。     

纳米银对华南毛蕨切叶的保鲜效应研究

试验探讨了新型抗菌剂纳米银(nano-silver,NS)预处理对华南毛蕨(Cyclosorus parasiticus)切叶采后的保鲜效应。结果表明,用0.5、1.0、2.0 mg/L NS溶液预处理华南毛蕨切叶24 h后再瓶插于去离子水中,可显著延长该切叶的瓶插寿命。进一步研究发现,NS预处理可显著改善华南毛蕨切叶的水分代谢,并有效延缓其鲜重下降和叶片萎蔫。     

采后蔬菜保鲜技术研究进展

蔬菜是人们日常饮食中必不可少的食物之一,但是其组织结构和生理特性使其容易发生腐败变质,因此采后蔬菜的保鲜效果对后期的贮藏加工十分重要.结合国内外研究进展,从物理保鲜技术、化学保鲜技术、生物保鲜技术3个方面对采后蔬菜的保鲜方法进行综述,同时指出目前国内蔬菜保鲜中存在的一些问题,并对未来采后蔬菜的保鲜技术进行展望.     

水产品冰温保鲜技术研究现状

水产品属于白肉具有肌纤维细腻、脂肪含量低且不饱和脂肪酸含量高等特点而受到广大消费者的青睐.另一方面,其独特的生物学特性使其极易腐烂变质,微生物是导致大部分水产品腐败变质的主要原因.介绍了冰温保鲜技术的产生、原理、特点、以及冰温保鲜技术结合其他保鲜技术对水产品的保鲜效果和影响冰温保鲜效果的因素等几个方面,并指出了冰温保鲜中存在的一些问题以及未来冰温保鲜的发展趋势.     

加强畜禽遗传资源保护与利用思路建议

本文对我国畜禽遗传资源保护已开展工作和取得的成绩进行了全面总结,分析了存在的主要问题,提出了进一步加强畜禽遗传资源保护工作的思路建议.     

Biodiversity functions of urban cemeteries: Evidence from one of the largest Jewish cemeteries in Europe

As the world becomes more urbanized, urban cemeteries may become increasingly valuable for biodiversity conservation as cemeteries are ubiquitous elements of the green infrastructure in cities worldwide. By implementing a multi-taxon approach at different spatial extents, we analyzed habitat functions of a large urban cemetery in Berlin (Weiÿensee Jewish Cemetery) and explored related environmental variables. This cemetery is an outstanding cultural heritage site but it also stands for old urban cemeteries that have progressed to urban woodland, an ecosystem type that exists in many regional and religious contexts. The cemetery provided a habitat for 604 species; species of conservation concern comprised 1.6⿿100% of total species among different groups of taxa (in decreasing order: bats, birds, lichens, bryophytes, carabids, vascular plants, spiders). Species richness and species composition at the plot level were significantly related to differences in management intensity and resulting vegetation structures but differed among taxonomic groups. In vascular plants, carabids and spiders, the species composition varied significantly with habitat age, and there was a set of characteristic species for different age classes in each species group. Our results thus support the use of differentiated management approaches to maintain habitat heterogeneity by allowing wilderness development in some parts of a cemetery while keeping others more open. Since these aims can be combined with efforts to preserve outstanding grave architectures and allow access to visitors, our study indicates ways of reconciling conflicting aims of heritage preservation and biodiversity conservation, a promising perspective for biodiversity conservation in culturally shaped urban landscapes. We conclude that cemeteries provide important cultural ecosystem services within the urban green infrastructure.     

食品脱氧剂配比的优化

[目的]探寻最佳脱氧效果的食品脱氧剂。[方法]对比不同配比的铁系脱氧剂在相同条件下的脱氧效果并比较铁粉活化程度对脱氧效果的影响。[结果]配比为0.3 g活化铁粉、0.1 g硅藻土、1 g Na2CO3.10H2O、0.2 g NaCl时脱氧效果最好。[结论]通过该实验获得了最佳脱氧效果的食品脱氧化剂配比。     

PLC在木材防腐设备机组中的应用

本文讨论了ＰＬＣ在满细胞法和频压法中的应用情况，说明了ＰＬＣ与快开门安全联锁的关系，阐述了推广ＰＬＣ控制的木材防腐设备机组的意义。     

晚播小麦覆膜增产作用研究

覆膜能明显的增温、保墒提墒、加速养分释放,对晚播小麦的根系生长及分蘖等起着重要的促进作用。为小麦健壮生长,增加群体,加快生育进程和增产创造了良好的有利条件。试验表明,覆膜后可使分蘖增加43.11％,次生根增加46.71％,单株干重增加108.78％,穗数增加69.10％,增产率达95.86％,纯收益1hm~2增加900多元。