Fatty acid profile of milk from goats fed diets with different levels of conserved and fresh forages

Aim of the study was to evaluate the effect of different proportions of hay and fresh grass in goats’ diet on milk fatty acid profile. Nine Camosciata goats were fed a fixed amount of concentrate (30% of total diet) and different percentages (40% vs 30%, 50% vs 20% and 60% vs 10%) of hay and fresh grass, respectively. Diminishing amounts of fresh grass percentages in the diet led to significant increases of lauric, myristic and palmitic acids (P ≤ 0.001) and to significant decreases of C18:1 t6‐11, rumenic and α‐linolenic acids (P ≤ 0.001) in milk, thus determining a worsening of the health value of milk fat.     

Grass as a high potential by-product: Buffalo grass to biogas and the increase of system performance and stability

Buffalo grass and alkaline-pretreated buffalo grass samples were co-digested with cow manure separately to generate biogas in anaerobic reactors. The study considered a solid content of 20% (10% buffalo grass and 10% cow manure). The methane (CH₄) content and CH₄ yield of the distinct experiments were compared. For the untreated buffalo grass, the weighed buffalo grass was mixed with cow manure and water. For the alkaline-pretreated buffalo grass, the weighed buffalo grass was soaked in 1% sodium hydroxide for 1 day prior to being mixed with cow manure and water. The untreated and pretreated buffalo grass-manure were fed semi-continuously at the rate of 125 mL/day for five days feeding in a 5 L reactor, with 40 days hydraulic retention time. The experiments were conducted for approximately 100 days. Results were reported when the systems were in steady-state conditions. The chemical oxygen demand (COD) conversion efficiency of co-digestion of the untreated and pretreated buffalo grass-manure were 46.21 and 62.76%, respectively, and for the total volatile solids (TVS) were 68.50 and 71.80%, respectively. The CH₄ contents generated from co-digestion of the untreated and pretreated buffalo grass-manure were 48.32% and 50.36%, respectively. The CH₄ yields generated from co-digestion of the untreated and pretreated buffalo grass-manure were 328 and 385 L/kgTVS conversion, respectively. It was observed from the experiments that pretreatment of the buffalo grass prior to co-digestion provided system stability during biogas production.     

草原石林：东北亚早白垩世花岗岩伸展穹隆和岩浆成矿爆发的地质遗迹及其形成过程

东北亚地区至少发育9个大型草原石林,属花岗岩石林的一种,是东北亚早白垩世巨量伸展和第四系冰川、风化作用的共同产物,主要特点是发育密集的近水平节理。本文通过整理岩浆岩专题填图和构造研究发现,这些石林的主体是早白垩世东北亚地区巨量伸展过程中形成众多的不对称花岗岩穹隆或同减薄岩体,岩体边部发育韧性剪切带,核部发布近水平岩浆流动面理,伸展和岩浆多期侵位导致与成矿密切相关的岩浆热液大量上涌,岩体抬升至地表,沿岩浆面理发育密集的近水平节理和部分垂直节理,后期沿这些构造面理发生的物理风化和化学作用(包括风蚀、冰川以及盐风化等)造就了千奇百怪的形态。草原石林是花岗岩地貌中的“另类”,不仅具有指示东北亚地区花岗岩形成时代(早白垩世)的特点,也是寻找晚中生代中国北方大规模成矿的良好标志体,而且风化形成的千姿百态的景色极具观赏价值,可以作为整个蒙古草原地区和大兴安岭南段地区特色的地学科普和生态旅游资源。     

草花在住宅景观中的运用

随着生活水平的不断提高，人们对居住环境的要求也日益提升，室外景观不但要满足功能需求，还要具有观赏价值。本文将从草花在住宅景观中的运用着手展开讨论。     

草屑厌氧消化预处理耦合水热炭化研究

厌氧消化（AD）耦合水热炭化（HTC）技术对园林废弃物的可持续资源化利用具有显著优势和意义。采用草为研究对象,进行了7~28 d的AD预处理,深入探究了AD预处理耦合HTC对水热炭特性及其热解和产物释放特性的影响。其中,AD促进HTC过程主要发生脱羧反应;通过改变木质纤维素构成比例和结构特征有效调控水热炭的功能特性。此外,AD打破了生物质内部致密的刚性结构,促进了水热炭丰富孔隙的形成和比表面积的增加。在生物可降解程度为17.52%（AD 7 d）时,水热炭性能最佳,质量产率、高位热值（HHV）、能量产率和能量密度分别达62.75%、23.81 MJ·kg^-1、80.31%和1.28。此外, TG-MS分析结果揭示了AD预处理提高了炭的热稳定性以及热解产物中能源气体的生成,有助于热解气的提质和利用。     

双组分聚氨酯人造草背胶的研制

介绍了一种双组分聚氨酯人造草背胶的制备方法,以聚醚多元醇、异氰酸酯为主体原料,3,3'-二氯-4,4'-二氨基二苯基甲烷(MOCA)为扩链剂,研究了不同聚醚多元醇质量比、扩链剂用量、异氰酸酯质量比、异氰酸酯指数对人造草背胶操作时间、脱粘时间及力学性能的影响。结果表明,当异氰酸根指数为0.99,A组分中聚醚多元醇MN-3050与DL-1000质量份数分别为80、20,A组分中扩链剂MOCA用量为4份,B组分中MDI-50与PM-200质量比为1∶1,当A、B组分按质量比2∶1混合时,操作时间及脱粘时间最佳,人造草背胶的综合力学性能达到最好。     

Impact of plant shoot architecture on leaf cooling: a coupled heat and mass transfer model

Plants display a range of striking architectural adaptations when grown at elevated temperatures. In the model plant Arabidopsis thaliana, these include elongation of petioles, and increased petiole and leaf angles from the soil surface. The potential physiological significance of these architectural changes remains speculative. We address this issue computationally by formulating a mathematical model and performing numerical simulations, testing the hypothesis that elongated and elevated plant configurations may reflect a leaf-cooling strategy. This sets in place a new basic model of plant water use and interaction with the surrounding air, which couples heat and mass transfer within a plant to water vapour diffusion in the air, using a transpiration term that depends on saturation, temperature and vapour concentration. A two-dimensional, multi-petiole shoot geometry is considered, with added leaf-blade shape detail. Our simulations show that increased petiole length and angle generally result in enhanced transpiration rates and reduced leaf temperatures in well-watered conditions. Furthermore, our computations also reveal plant configurations for which elongation may result in decreased transpiration rate owing to decreased leaf liquid saturation. We offer further qualitative and quantitative insights into the role of architectural parameters as key determinants of leaf-cooling capacity.     

香根草在铁路路基边坡防护中的机理和应用

铁路边坡防护直接影响列车运行安全,文章介绍了香根草国内外应用及其生物和工程特性,以及在铁路上的试验应用和具体实例,说明了香根草在铁路边坡防护上应大力推广和应用是符合可持续性发展要求的。