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为探究淡干海参泡发工艺,以烟台淡干海参为原料,通过正交试验得到最优工艺条件为:121 ℃、0.12 MPa高温高压处理20 min,全程使用蒸馏水,泡发温度4 ℃,泡发时间48 h,采用该工艺泡发的海参质量和长度分别为泡发前干海参的14.5倍和2.7倍,复水比为9.2,其硬度、弹性、适口性、持水力及营养价值均高于市面上常压煮制常温泡发的海参。该研究结果为科学、方便地食用和推广淡干海参提供了理论依据。 相似文献
3.
为探究NaHCO3前处理对不同种类生物炭性质及其磷吸附能力的影响,借助元素分析、光电子能谱、孔径分析、扫描电镜等手段对比处理前后秸秆、壳核及其他3类生物炭表面特性和孔结构的差异,基于吸附等温线和Freundlich与Dubinin-Radushkevich模型拟合,探讨生物炭性质控制磷吸附的机理。结果表明:NaHCO3前处理总体提高了各类生物炭的比表面积和孔体积,增幅分别为2.70%~110.84%和1.42%~123.80%,提高其芳香性(C=C),H/C增幅为5.56%~29.41%,同时降低了极性官能团(C—O和C=O)含量,极性指数[(O+N)/C]降幅为13.18%~46.34%。原始生物炭的磷释放量范围为78.33~568.33 mg·kg-1,NaHCO3前处理显著增加各类生物炭对磷的吸附,使其表现出近似的磷吸附能力(Freundlich吸附系数KF范围为119~254 mg1-n·Ln·kg-1)... 相似文献
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本研究旨在探究寒旱百合种植区地表覆草技术对土壤水热状况、理化性质、百合生长和产量的影响。采用随机区组设计,试验处理为露地(CK)、地表覆草(S)、地膜覆盖(M),3次重复,共计9个处理。结果表明,百合地表覆草技术可以明显改善土壤水热状况,提高土壤理化性质指标含量,增加百合产量。相对于对照露地处理,表层土壤温度和含水量分别增加了18.86%、16.01%,土壤有机质、碱解氮、速效磷、速效钾含量分别提高了75.61%、18.12%,21.04%、10.41%,株高、茎粗、球横径、球纵径、单球重和产量分别增加了8.26%、22.22%、16.55%、23.47%、32.83%、35.07%。综上所述,在寒旱百合种植区,地表覆草技术是一项重要的田间管理措施。 相似文献
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L. Lidfors 《Veterinary research communications》1989,13(4):307-324
The aim of this review is to find out if getting up and lying down movements can be used as one of several parameters when evaluating different cattle environments. Getting up and lying down movements are performed according to innate movement patterns. An unsuitable environment can cause these movements to become incomplete or abnormal and so lead to injuries. Physiological measurements at lying down show a greater change in tethered cattle than in cattle kept on deep litter. In short stalls the use of certain types of tethers and the height of the manger edge affect the normal getting up and lying down movements. Unsuitably designed cubicles in loose housing systems can lead to changed movement patterns. Calves and fattening bulls have fewer lying down and getting up movements and longer lying intervals on slatted floors than on deep litter. Calves kept in small individual crates carry out a large percentage of their lying down and getting up procedures abnormally. In this review it is shown that it is possible to make improvements in the environment of cattle by using results from studies of these behaviour patterns. The conclusion is that getting up and lying down movements can be used as one of several parameters when evaluating different cattle environments. 相似文献
7.
T. SVÅSAND O. T. SKILBREI G. I. VAN DER MEEREN M. HOLM 《Fisheries Management and Ecology》1998,5(6):473-490
Abstract The main question which must be raised when planning to enhance natural populations through sea ranching is whether reared organisms are fit for a life in the wild, or more specifically, whether there are differences between reared and naturally resident individuals. The causes and effects of these differences are reviewed, and results from the Norwegian enhancement programme, which compared reared and wild individuals of Atlantic salmon, Salmo salar L., Atlantic cod, Gadus morhua L., and European lobster, Homarus gammarus L., are discussed with emphasis on morphological and behavioural differences. It was concluded that exposure to an artificial rearing environment during ontogeny can affect both the phenotype and the behaviour of the reared individuals, and thereby, their potential for survival after release into the wild as well. Suggestions are made as to how to diminish observed differences, and thereby, improve the survival potential. 相似文献
8.
Frank David Cdric Hubas Helne Laguerre Aicha Badou Gwen Herault Tho Bordelet Nadia Ameziane 《Aquaculture Nutrition》2020,26(5):1568-1583
Various research projects in Europe and North Africa have recently intended to breed temperate holothurians to alleviate fishing pressure on natural populations. However, to date little is known about the nutritional requirements of East Atlantic and Mediterranean species. In this study, we propose a “natural population”‐oriented approach to characterize food sources, digestive efficiency and resources allocation based on the composition of pigments and fatty acids (FA) in gut contents and tissues (muscles, gonads and digestive tract walls) of wild individuals of the species Holothuria (Panningothuria) forskali (Delle Chiaje, 1823) sampled in Brittany (France). Our study reveals that neither green nor red algae enter the diet of H. forskali in spring and that the only fresh vegetal material found in gut contents is brown algae (very likely diatoms). The high nutritional quality of gut contents however contrasts with the detrital nature of the ingested food sources, suggesting that a trophic upgrading of organic matter occurs before digestion. In addition, unusual FA (i.e. only present in a few groups of living species) such as long‐chain monounsaturated FA (especially the FA 23:1ω9) were found in large proportions in muscles and gonad and their effect on sea cucumber fitness needs further investigation. 相似文献
9.
Hiroto Murase Toshihide Kitakado Takashi Hakamada Koji Matsuoka Shigetoshi Nishiwaki Mikio Naganobu 《Fisheries Oceanography》2013,22(3):154-173
The spatial distribution of Antarctic minke whales in the Ross Sea with relation to spatial distributions of their prey – krill – was investigated in this study using generalized additive models (GAMs). Spatial distributions of two species of krill (ice and Antarctic krill) were estimated by GAMs. Three abiotic factors – distance from the continental shelf break (800 m isobaths), the mean temperature and salinity from the surface to 200 m (MTEM‐200 and MSAL‐200), and latitude and longitude – were used as covariates for models of krill. Estimated spatial distributions of krill were then used with other covariates to model the spatial distribution of Antarctic minke whales. In the selected model of Antarctic minke whales, Antarctic krill were more influential than ice krill. The number of Antarctic minke whales increased as the density of Antarctic krill increased to around 1.5 g m?2. Beyond that, the number of Antarctic minke whales decreased as the density of Antarctic krill increased. High densities of the Antarctic minke whales were estimated along the sea ice edge in the eastern part of the Ross Sea. Specifically, the densities were high in the north of the continental shelf break where low MTEM‐200 and MSAL‐200 and intermediate densities of Antarctic krill were observed. Further data collection is needed to investigate interannual variations and trends in their relationship. The results show that the spatial distribution of Antarctic minke whales is a function of longitude, distance from the shelf break, oceanographic condition (temperature and salinity), and densities of ice and Antarctic krill. 相似文献
10.
四季鹅产蛋前后腺垂体远侧部细胞的超微结构比较 总被引:2,自引:1,他引:2
对处于产蛋、停产和产前等不同时期的四季鹅腺垂体远侧部分泌促激素的6类细胞,即促生长激素细胞(α细胞)、催乳激素细胞(η细胞)、促卵泡形成激素细胞(β细胞)、促黄体生成激素细胞(γ细胞)、促甲状腺激素细胞(δ细胞)及嫌色细胞等的超微结构作了比较观察。结果表明,产蛋期嗜碱性β、γ和δ细胞呈旺盛的细胞结构象,细胞器结构发达,腺体功能活跃;停产期特征是η细胞稍增多,细胞器少,腺体功能处于相对静止;产前期仅α细胞功能活跃,嫌色细胞数量较多,此时腺体功能低下。 相似文献