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71.
武定鸡、茶花鸡肉用性能及肉质的研究   总被引:2,自引:0,他引:2  
 测定武定鸡,茶花鸡不同年龄,不同性别的体态结构及肉的品质,进一步研究两品种肉用性能和各种氨基酸的含量。结果表明,由于种质特性不同,体态结构有差异,武定鸡为0.14~0.15,茶花鸡为0.16~0.19;屠宰率,全净膛率,胸、腿肌率,净肉率,两品种间同龄,同性对应相比均无显著差异。各品种内500日龄的净肉率极显著高于90日龄;肌肉中蛋白质,脂肪含量也是500日龄母鸡高于90日龄同品种的公母鸡,而含水量则下降。谷氨酸的含量,武定鸡的公母分别是18.23%,17.23%;茶花鸡的公母是17.43%,19.07%;已报道的太和鸡是18.31%,17.65%,三者极为近似.赖氨酸武定鸡胸、腿肌分别为9.33%,9.45%;茶花鸡为8.94%,9.41%;太和鸡为8.84%,9.08%;武定高于太和鸡和茶花鸡。  相似文献   
72.
Diatoms are unicellular algae with plastids acquired by secondary endosymbiosis. They are responsible for approximately 20% of global carbon fixation. We report the 34 million-base pair draft nuclear genome of the marine diatom Thalassiosira pseudonana and its 129 thousand-base pair plastid and 44 thousand-base pair mitochondrial genomes. Sequence and optical restriction mapping revealed 24 diploid nuclear chromosomes. We identified novel genes for silicic acid transport and formation of silica-based cell walls, high-affinity iron uptake, biosynthetic enzymes for several types of polyunsaturated fatty acids, use of a range of nitrogenous compounds, and a complete urea cycle, all attributes that allow diatoms to prosper in aquatic environments.  相似文献   
73.
Nineteen parental lines including five male sterile A-lines (AH002A, AH003A, AH209A, S5001A, J16A) and fourteen restorers (A1-GH, A3, S5, J6, J7N, J7J, J8, J9, J10, J11, J12, J13, J14, J17) were crossed using the North Carolina II statistical method. Studies of combining ability and heritability were conducted on selected parents along with their seventy F1 hybrids for main ornamental traits. Plant height, crown size and length of node had obvious additive genetic effects, high (>0.50) broad sense heritability and high narrow sense heritability (length of node was medium). Pedicel length showed approximately equivalent maternal and paternal additive genetic effects, high broad sense heritability and medium (0.30–0.50) narrow sense heritability. Number of whorls of ray florets across capitulum and number of branches were able to take advantage of heterosis. The relationship between general combining ability and specific combining ability in Zinnia elegans depended on materials and traits. Male sterile two-type line was pivotal in the hybridization breeding of Z. elegans. S5001A, AH002A and A1-GH, A3, J14 which performed high negative GCA effects in PH, PL, LN and type I in PH, PL, NW, LN were ideal female and male parents of potted flowering plants; AH209A, J16A and S5, J10, J17 which displayed positive GCA effects and almost type I in PH, PL, LN were ideal female and male parents of cut flowers, respectively. For potted flowering plants, AH002A × J17, AH209A × A1-GH and S5001A × J6 with high negative SCA effects in PH, PL and LN were the most promising combinations, AH002A × S5, AH003A × A3 and J16A × J6 were the subprime combinations; for cut flowers, AH209A × S5, AH209A × J17 and J16A × J17 with high positive SCA effects in PH, PL and LN were the primary combinations, AH209A × J9 and S5001A × J10 were the secondary combinations.  相似文献   
74.
浙江共有豆科植物61属,181种,3亚种,7变种,3变型,其中栽培15属,57种,2变种,2变型。本文通过对各自然分布属在豆科中系统位置的分析,分布区类型的统计和与邻近地区豆科植物属、种的对比,认为浙江豆科植物区系种类丰富,起源古老,地理成分复杂,具有较明显的热带和亚热带性质,与邻近地区的关系密切,为一个开放型的植物区系。同时还探讨了地理分布格局,证实了以括苍山,仙霞岭一线为界的浙江东南部是华东、华南两植物区系的交汇地带。吴征镒将雁荡山、洞宫山一线以南的浙江东南一隅划为华南区系的范围是合理的。  相似文献   
75.
简述了红壤丘陵区综合开发经营管理体制系统构成及其重要性。分析了千烟洲试区农村经济及典型生态农户经济效益,并对发展生态农户提出了几点建议。  相似文献   
76.
通过对现有地下灌溉系统的分析,论述了田间地下土基透水管灌溉、排水兼用的可行性及机理分析。在对国内外暗管施工机进行分类归纳的基础上,研制出土基透水管现场成型机,可现场一次完成土基管的成型、固壁、防渗、镶嵌渗水条等工序,初步对样机进行了田间试验,验证其结构合理性、经济性、并对土壤的破坏成型机理进行了分析  相似文献   
77.
绍兴市农业生态和农业气象灾害监测预警系统   总被引:3,自引:0,他引:3  
通过建立基于3S技术的农业生态监测和基于自动气象站、雷达、卫星、数值预报、短信息技术的农业气象灾害监测预警系统,动态监测绍兴市耕地被侵占面积,分析水资源分布、土地利用覆盖等农业自然资源分布特征,并对农业气象灾害实现监测和预警,从而为根据当地自然资源优势,通过农业结构调整,有效地减轻气象灾害损失,促进农业可持续发展提供技术支撑。  相似文献   
78.
针对现有瓜科嫁接机砧木生长点去除不干净,以及生长点去除过程中砧木苗易损伤的缺点,该文以葫芦苗为试验对象,通过瓜科蔬菜砧木苗生长点去除理论运动轨迹分析和对生长点去除机构的动力学分析,设计开发了一种应用于瓜科蔬菜嫁接的生长点去除机构,该机构利用模仿人工方法通过手指去除生长点的原理,采用曲柄连杆机构外加柔性手指,实现生长点的去除。试验结果表明,砧木苗在13~17 d培育期间内,所设计的机构能较好地去除砧木苗生长点,去除成功率达90%以上,伤苗率小于5%,所研发的瓜科蔬菜嫁接砧木生长点去除机构是可行的。该研究可为解决蔬菜嫁接砧木苗生长点去除困难提供参考。  相似文献   
79.

Purpose

Remediate metal contamination is a fundamental step prior to reclaim oil sands tailing ponds, and copper (Cu(II)) is the most abundant metal in the tailings water or oil sands process-affected water (OSPW). Biochars produced at four pyrolysis conditions were evaluated for sorption of Cu(II) in synthetic OSPW to explore different biochar potentials in removing Cu(II) from the contaminated water.

Materials and methods

Pine sawdust biochars pyrolyzed at 300 and 550 °C with and without steam activation were investigated by batch sorption experiments. Isotherm and kinetic studies were conducted to compare the sorption capacities of the four biochars and to examine potential mechanisms involved.

Results and discussion

For all the biochars, Langmuir and pseudo-second order models were the best-fit for isotherm and kinetic studies, respectively. According to the Langmuir parameters, the maximum adsorption capacities of the biochars produced at 550 °C were around 2.5 mg Cu(II)?g?1, which were 30-folds higher than those produced at 300 °C. However, steam activation did not cause any significant difference in the biochars’ sorption performance. The kinetic study suggested that chemisorption involving valence forces was the limiting factor of the sorption. In addition, ion exchange and precipitation were likely the primary mechanisms for Cu(II) sorption which outweigh complexation with functional groups on the biochars’ surface.

Conclusions

Pine sawdust biochar produced at 550 °C without steam activation could be utilized as a sustainable and cost-effective material to remove Cu(II) from the OSPW.
  相似文献   
80.
Water, Air, & Soil Pollution - Aquatic Hg contamination extending more than 200 km along the South River, South Fork of the Shenandoah River, and Shenandoah River in western VA has been...  相似文献   
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