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排序方式: 共有235条查询结果,搜索用时 157 毫秒
41.
Zabihallah Bahmani Masoud Rezaei Seyed Vali Hosseini Seyed Fakhreddin Hosseini Alireza Alishahi Mehraj Ahmad 《Journal Of Aquatic Food Product Technology》2013,22(6):542-551
Research has shown that fresh fish is an extremely perishable food as compared to other food commodities. In this study, quality deterioration during storage of golden grey mullet (GGM) iced for 0, 6, and 12 h after landing was monitored. Microbiological indices (total viable count, TVC; psychrophilic counts, PTC; lactic acid bacteria, LAB; and Enterobacteriaceae counts, EBC), chemical parameters (pH; total volatile basic nitrogen, TVB-N; peroxide value, PV; thiobarbituric acid, TBA; and free fatty acids, FFA) values increased over the preicing duration. Delayed icing did not lead to significant increases (p > 0.05) in TVC, PTC, LAB, and EBC throughout the period of storage. All chemical indices increased during storage (p < 0.05). This study showed that sensorial analysis of GGM correlated well with microbiological analysis. Results of this study based on the microbiological and raw fish sensorial data indicated that the shelf life of GGM stored in ice immediately after catch was approximately 10–11 days, while the 6- and 12-h delays in icing shortened the shelf life to approximately 6–7 and 2–3 days, respectively. 相似文献
42.
Fui Fui Ching Yoshizumi Nakagawa Keitaro Kato Osamu Murata Shigeru Miyashita 《Aquaculture Research》2012,43(2):303-310
The effects of delayed first feeding on the survival and growth of tiger grouper, Epinephelus fuscoguttatus (Forsskål 1775), larvae were examined under controlled conditions. The total length, yolk sac volume, oil globule volume, yolk sac absorption time and nutritional transition period (NTP) of the larvae fed at different first times (0, 6, 12, 18 and 24 h after the mouth opening stage; h AMO) were compared. Larval first feed intake was observed at 54 h after hatching (h AH) at 27.5 ± 0.5 °C. The yolk sac was consumed more rapidly with an increase in delayed first feeding and was significantly different among treatments (P<0.05). Larvae first fed at 0 h AMO had the longest yolk sac absorption (72 h AH) and NTP (20 h) times and had the highest survival and growth rates at the end of the experimental period (360 h AH), being significantly higher (P<0.05) than the other treatments. First mortality was observed at 69 h AH, approximately 2 h after point of no return (PNR) occurred. This study suggests that first feeding of tiger grouper larvae should commence at 0 h AMO for enhancement of larval survival and growth. 相似文献
43.
为研究排卵延迟奶牛发情配种后黄体的变化规律及其差异性,本研究在临床症状观察、直肠检查和B超辅助检查诊断的基础上,选取8头排卵延迟奶牛(排卵延迟组)、5头健康正常发情奶牛(对照组),应用B超对黄体的相关指标(直径、面积、周长和体积)进行了测量及分析,对获得的不同阶段典型黄体声像图进行了描述。结果显示,与对照组相比,排卵延迟组与对照组奶牛黄体的直径、面积、周长和体积在发情配种后7~15 d差异均不显著(P>0.05)。在发情配种后第9和13天排卵延迟组奶牛黄体相关指标(直径、体积、面积和周长)大于对照组奶牛,而在第11天小于对照组奶牛。结果表明,排卵延迟奶牛发情后不同阶段B超黄体直径、面积、周长和体积与正常发情排卵后的相应指标没有显著差别。 相似文献
44.
针对目前生物延迟发光检测系统利用外置激发光源存在的延迟误差和自然光叠加干扰导致的测量结果重复性不好和可靠性差的问题,设计了一种生物延迟发光辐照光源系统。该光源系统主要由恒温辐照室、三基色RGB-LED(light-emitting diode)矩阵辐照光源、电子快门隔离器及控制电路组成,并与BPCL系列微弱发光测量仪组装在一起使用。在51系列单片机的控制下,该辐照光源系统实现了光源频率和光强的多重选择以及辐照时间的程序化操作,实现了光照与检测之间在同一个暗室通道中通过电子快门的迅速切换,极大的降低了自然光的叠加干扰与延迟误差。背景噪声和稳定性试验测试结果表明,应用该系统使平均光子计数的噪声偏差不超过4.5 cps,5次重复测试的相对误差为0.7%,重复测试的延迟发光曲线具有良好的重合度。对萌发玉米延迟发光的测试结果表明,延迟发光曲线的拟合优度R2在0.99以上,应用该系统可以得到较为理想的结果。 相似文献
45.
为研究延迟荧光光谱特性与植物耐热性的关系,该文以3种不同品种的植物为研究对象,分析了温度胁迫下样品延迟荧光发射光谱曲线的变化情况,研究了各样品延迟荧光光谱中685 nm附近峰值(标记为F685)与730 nm附近峰值(标记为F730)的光谱峰值比F730/F685的温度响应曲线,并与叶绿素荧光参数的温度变化趋势进行对照,探讨了温度拐点出现的原因及变化趋势。试验结果证实延迟荧光发射光谱F730/F685温度响应曲线的变化真实地反应了植物在高温胁迫下光系统的光合功能,有效地体现了样品间对高温逆境响应的差异,且温度响应曲线的拐点及其变化特性可能会是一种鉴定植物耐热性的有效指标。 相似文献
46.
在新型可降解材料聚乳酸-聚三亚甲基碳酸酯(PLA-PTMC)中加入含量约为30%的兽药恩诺沙星,于家兔体内、体外观察其降解和释药特性.结果发现,第10周时体外药物释放率约为80%,110 d时体外材料降解率约为48%;体内第6周时材料开始破碎,第10周时破碎完全.因此,PLA-PTMC是一种降解性、释药性及生物相容性均良好的外科用可降解材料. 相似文献
47.
Teresa NAVARRO 《干旱区科学》2021,13(9):962-976
The ability of plants to safely retain seeds in the mother plant is an adaptive mechanism described in many desert plants. However, research about delayed seed dispersal species in the desert of the United Arab Emirates (UAE) is lacking. This study aims to identify these delayed seed dispersal species and assess the relationships of the presence of delayed seed dispersal with plant growth form, habit, spatial dispersal, antitelechoric mechanism, and seed release time. The relationships between the presence of delayed seed dispersal and the above studied traits were assessed by using the Pearson Chi-square test and Nonlinear Principal Components Analysis (NLPCA). Results showed that a total of 46 delayed seed dispersal species were recorded (15.0% of 307 studied species) and the highest incidence occurred in the Fabaceae family (17.4%). Delayed seed dispersal species were predominantly perennial plants (73.9%) with spatial restricted dispersal (67.4%), which released seed in the dry season (45.7%). The dominant groups of delayed seed dispersal species were persistent fruits species and synaptospermy (28.3%). All graminoids showed persistent lignified fruits, while prostrate annuals were basicarpic species with myxospermy. Sandy habitats had the highest number of delayed seed dispersal species (54.3%), whereas salt flats had the lowest (23.9%). In the desert of the UAE, delayed seed dispersal species spread seeds until the end of the dry and windy season, thus breaking seed dormancy at this time and ensuring seed germination in the next arrival of the rainy season. This morphological and ecological adaptation of delayed dispersal species is essential to the survival and sustainable development of vegetation in desert environments. 相似文献
48.
Valéria Carpentieri-Pípolo Leones Alves de Almeida Romeu Afonso de Souza Kiihl Ciro Antonio Rosolem 《Euphytica》2000,112(2):203-209
The long juvenile period characteristic (LJP), which delays flowering under short day conditions, has been identified in soybean
cultivars (Glycine max L. Merrill). This characteristic may be especially important as it increases the range of adaptation of soybean in low latitudes
and gives greater flexibility for sowing periods within the same latitude. The inheritance of the long juvenile period was
studied in the BR80-6778 soybean line to provide knowledge to support the development of cultivars adapted to short day conditions.
Cultivars with classic flowering, Paraná, Bossier, Bragg and Davis, which flower early under short day conditions, were also
used as parents in single crosses. They were crossed among themselves and with the genotypes with LJP, BR80-6778 and MG/BR
22 (Garimpo). The study was carried out under short day conditions (early sowings) in greenhouses and in the field at Embrapa
National Soybean Research Center, Londrina, PR. Flowering was assessed daily. The results indicated that the BR89-6778 line
shares a pair of alleles with the Paraná cultivar, and when associated with the cc allele retards flowering under short day conditions. The following genotype constitutions were attributed to the cultivars:
Paraná (aaBBCC), Bossier (AabbCC), and BR80-6778 (aaBBcc). The combination of the genes aabb and aabbcc has a pronounced effect on the manifestation of the trait.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
49.
50.
吉林省向日葵菌核病综合防治措施研究及大面积应用效果 总被引:2,自引:0,他引:2
在重茬4年的重病地块晚播(5月20日—25日)向日葵,其花腐型菌核病比正常播期(4月25日)减少90%以上,而产量提高13%—30%。在农村扩大示范,晚播(5月19日)减少病害59%—75%,产量提高35%。在盛花期—成熟期喷2—3次50%速克灵500倍液可大大减轻花腐型菌核病的发生(防治效果65.9%—92.3%)。经筛选以速克灵(0.5%)拌种防治根腐型菌核病效果最好,在温室中对土壤和种子中的病菌防治效果达83%以上,小区试验和农村示范防治效果达55.8%—100%。土壤中增施钾肥可提高植株抗病力,减轻发病。1990年在吉林省农安、长岭2县8533ha采用晚播、轮作2年以上、种子处理、增施钾肥、盛花期—成熟期喷药的一套综合防治措施,重点调查10块对比田,花腐型菌核病平均防治效果为87.62%(63.38%—100%),对根腐型菌核病防治效果平均为66.77%(50.0%—82.57%)。1991年在长岭、农安等6个主产区推广6.37万ha,重点调查134块对比田,花腐型菌核病防治效果平均为75.86%(46.37%—100%),根腐型菌核病平均防治效果为65.11%(33.33%—100%),增产增收显著。 相似文献