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81.
用丙酸钙、山梨酸、富马酸及富马酸二甲酯四种防霉剂以0.2%,0.5%的剂量分别处理水分为16%的酵母饲料,置于27~30℃的恒温箱中,在模拟高温季节流通过程的条件下,进行防霉保鲜试验。试验期对样品的感观、粗脂肪、粗蛋白、带茵量等指标定期检测的结果表明,浓度为0.5%的山梨酸防霉效果最好,无霉变期达11天;0.5%的丙酸钙防霉效果次之,无霉变期为9天,富马酸及富马酸二甲酯的防霉效果欠佳。饲料成分中以粗脂肪含量在试验期间减少最明显。 相似文献
82.
Influence of alpine plants growing on steep slopes on sediment trapping and transport by runoff 总被引:1,自引:0,他引:1
Understanding the interactions between soil and the organisms that are conducive to decreasing sediment runoff is a great concern on high-elevation ski trails. Intense rainfalls on steep slopes combined with soil formed on gypsum result in recurrent erosion. This study was conducted in the northern French Alps to determine the abilities of species: (1) to make mounds and (2) to trap sediment and thereby to control erosion at the slope scale. We also investigated relevant above-ground plant characteristics related to those abilities. Sediment runoff or deposition was investigated at small and large spatial scales. We assessed whether hoof prints in soil reflect sediment runoff at the slope scale by trapping sediment. Populations of plants growing on two slope angles (25° and 35°) and three vegetation cover densities (15%, 35%, 60%) were surveyed. An experiment was also conducted to measure the sediment deposit upslope of target species and over three months during the autumn. Small mounds were found upslope of the plant and sediment deposit measurements showed that they resulted from a sedimentation process. Nevertheless the species differed in their capacity to make mounds. Sesleria caerulea and Festuca alpina had the highest amount of sediment deposition over the experimental period. Among the plant characteristics, plant length was positively correlated with mound area, while the roundness index of the canopy was negatively correlated with mound height. Mound formation was also positively related to the number of tillers or shoots. Sediment accumulation in cow hoof prints was linked to runoff that occurred at the slope scale. Low deposition in hoof prints means low sediment runoff or a large deposition on mounds, due to the increase in vegetation cover. All the findings stressed that understanding the processes in action at larger scales requires studying processes at smaller scales. 相似文献
83.
黄土高原治理中的委托—代理关系及激励机制 总被引:1,自引:0,他引:1
根据委托—代理理论 ,对黄土高原治理中的参与方进行了辨析。分析了现存的委托—代理关系中存在的问题 ,设计出了新的激励与约束机制 ,使代理人能够按照委托人的意志行事 相似文献
84.
Ex-situ soil washing technology offers advantages such as speed and efficiency of remediation and range of application and has been developed to conform with legal requirements and best management practices in USA and some European countries. In this study,nano-sulfonated graphene(SGE) was used as a washing agent to evaluate different processing(washing) parameters for the ectopic leaching removal of polycyclic aromatic hydrocarbons(PAHs) from a coking plant soil. X-ray photoelectron spectroscopy(XPS) and fourier transform infrared spectroscopy(FTIR) were used to analyze the characteristics of the SGE tested. The results showed that SGE had a strong adsorption capacity for PAHs through the role of π-π, H-π, and anion-π interactions. The washing parameters, an SGE concentration of 2 000 mg L~(-1), a liquid/soil(L/S) ratio of 10:1, and 4 cycles of successive washing, were set to arrive to the optimum condition for achieving more than 80% of PAH removal. Under the optimum condition, the PAH removal rate decreased with increasing ring numbers. After one washing cycle at SGE concentration of 2 000 mg L~(-1) and L/S ratio of 10:1, the PAH removal rate of the SGE tested was much higher than that of Tween 80(TW80) or methyl-β-cyclodextrin(MCD)(P 0.01). Therefore, SGE is a promising material for the nanoremediation of PAH-contaminated soils. 相似文献
85.
Bud pollination and hybrid seed production in detergent-induced male sterile plants of Brassica juncea 总被引:2,自引:0,他引:2
The efficacy of a synthetic detergent (Surf Excel) as a potential chemical hybridizing agent in Brassica juncea was studied. Foliar sprays with various concentrations of the detergent caused reductions in plant height, number of branches and leaves per plant, size of leaves, anther size, pollen per flower, ovules per flower, pollen fertility, fruits per plant, fruit size, seeds per fruit, total yield per plant and 100 seed weight as compared with those of untreated plants. The style in the floral buds of plants sprayed with different concentrations of Surf Excel elongated and so the receptive stigma protruded from the buds which facilitated cross‐pollination by honey bees. The plants sprayed once with 2% Surf Excel exhibited an elongated style with a raised receptive stigma and 100% pollen sterility without causing a significant reduction in total yield. 相似文献
86.
以贵妃枇杷(Eriobotrya japonica Lindl.)为试材,采后以1%壳寡糖、1.0μL/L 1-MCP单一及复合处理,处理后置于20℃、相对湿度85%~95%环境中贮藏,分析不同处理对果实贮藏品质的影响。结果表明:壳寡糖与1-MCP熏蒸复合处理较两者单一处理更能降低枇杷果实的失重率、腐烂率,保持果色;延缓果实还原型抗坏血酸、可溶性固形物、可滴定酸含量的下降;抑制枇杷果实的呼吸强度、相对电导率的上升;显著改善果实贮藏期间的感官品质、营养品质;1%壳寡糖+1.0μL/L 1-MCP熏蒸复合处理技术比两者单一处理具有更好的保鲜效果。 相似文献
87.
88.
为了探究复合微生物菌剂615在甜脆豌豆栽培中的田间应用效果,以甜脆豌豆品种‘长寿仁’为试材,研究了4种施肥处理(不施肥对照,单施复合菌剂615,单施化肥,化肥+复合菌剂615配施)对主要农艺性状、产量和品质、根际微生物数量的影响。结果表明:所有施肥处理可显著提高结荚率(幅度为7.90%~12.49%),单施菌剂的病害率减少10.83%;所有施肥处理均可显著增加小区产量(幅度为10.75%~19.82%),其中化肥与菌剂配施增幅最大(19.82%)。单施菌剂使鲜食籽粒的总糖、蛋白和淀粉含量增加50.00%、9.24%和59.37%(p<0.05),其开花结荚期根际中的细菌、真菌和放线菌数量是苗期的1.93倍、2.38倍和2.36倍,化肥与菌剂配施可提高总糖和淀粉含量(p<0.05)。综合经济和生态效益,甜脆豌豆施肥推荐化肥与复合菌剂615配施。 相似文献
89.
化学杂交剂SQ-1诱导糜子雄性不育效果研究 总被引:2,自引:0,他引:2
采用裂区试验设计, 以喷药时期为主区, 喷药剂量为副区, 探讨了用SQ-1诱导产生的雄性不育率、杂交率及自然授粉结实率3项指标评价应用效果。结果表明, 喷药时期、喷药剂量及时期与剂量一级互作显著或极显著影响不育率和杂交率。在雌雄蕊原基分化期, 喷药剂量为4.0和5.0 kg hm-2时诱导雄性不育率、杂交率都在95%以上; 花粉粒分化形成初期, 喷药剂量为5.0 kg hm-2时诱导雄性不育率和杂交率都在95%以上。喷药时期对自然授粉结实率影响不显著, 剂量及时期与剂量一级互作影响显著, 自然授粉结实率随着剂量的增加呈降低趋势。SQ-1用于糜子的最佳时期为雌雄蕊原基分化期, 最适剂量4.0 kg hm-2。 相似文献
90.
早稻种子包衣直播育秧研究 总被引:5,自引:1,他引:5
早稻不催芽直播育秧,抗寒力强,成秧率高,可早播、早熟和省工、省种。是传统育秧方法的创新。种衣剂有防治病、虫、鼠害和营养壮苗作用,它与直播育秧技术结合,可以不侵种直播干谷,又使种衣剂免于在浸种中溶解淋失,两者优势互补,合成一项具有高科技结晶,操作性强。新型实效,简单易行的育秧技术。 相似文献