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Industrial processing of livestock, poultry and fish produces a large amount of waste in a solid or liquid form that can either be destroyed or be used to make compost, biogas or other low-added value products. However, the by-products from animal processing industries have a potential for conversion into useful products of higher value, such as protein hydrolysates, with interesting applications in animal feed. Low amounts of animal protein hydrolysates included in aqua-feeds may enhance growth rate and feed conversion of farmed fish and crustacean. Animal protein hydrolysates may also be incorporated in diets to enhance the nonspecific immunity of fish. As well, these hydrolysates can be used as a good source of amino acids for newly weaned animals. Protein hydrolysates from animal by-products including antimicrobials, antioxidants, opioid-like and/or other interesting bioactive molecules have promising and interesting applications on companion and production animals. By-products from animal processing industries are therefore a promising source of bioactive peptides of considerable interest for animal care, always within the framework of the existing legislation. Possible drawbacks and future trends of the use of animal by-products and/or production of protein hydrolysates from those materials are also discussed. 相似文献
84.
为研究高校既有建筑室内人群散发对室内VOCs的影响,对高校不同人群样本的教室及会议室两类典型人群密集房间,共82个人群样本对象进行了VOCs采样分析,得到不同实际场景下的人员相关的VOCs浓度水平,并对其潜在的影响因素进行分析。结果表明,共确认了29种与室内人员相关的高检出率且较高浓度值的物质,包括芳香族化合物9种,烷烯烃类9种,酮类和醛类8种,醇酯类以及卤化物3种,并得到主要VOCs物质的浓度水平和I/O比。对影响因素的统计分析表明,室内人员密度、季节和房间类型对不同VOCs物质存在显著性影响,其中季节性因素对目标VOCs污染物影响最为广泛,其次是房间类型与室内人员密度。该研究可为进一步了解人员密集室内VOCs污染现状及控制策略提供一定的科学参考。 相似文献
85.
Jet fuel range branched alkanes were first synthesized under solvent-free conditions by the aldol condensation of furfural and 3-pentanone from lignocellulose followed by the one-step hydrodeoxygenation (HDO). Among the investigated solid base catalysts, CaO and KF/Al2O3 demonstrated the highest activity for the aldol condensation reaction of furfural and 3-pentanone. The aldol condensation product of furfural and 3-pentanone (liquid at room temperature) was directly hydrodeoxygenated to 4-methyl-nonane and 4-methyl-octane. These alkanes have low freezing points (174.1 K and 159.8 K) and can be blended into jet fuel without hydroisomerization. Among the investigated HDO catalysts, the Ni-Cu/SiO2 exhibited the best performance. 相似文献
86.
《Journal of the European Ceramic Society》2020,40(8):3348-3353
Large transduction coefficient () is difficult to obtain in piezoelectric ceramics because these two parameters show opposite trends with compositional modifications. Herein, the Pb(Zr0.53Ti0.47)O3 ceramic powders were calcinated under different temperatures (A:830 °C, B:860 °C, and C:890 °C), and then mixed together according to different weight ratios (1A:1B:1C, 1A:2B:1C, 1A:2B:3C and 3A:2B:1C) for ceramics preparation. Both d33 and g33 are improved successfully, and the transduction coefficient with the weight ratio of 1A:2B:3C reaches up to 17,500 × 10−15 m2/N, which is 60 % higher than that with the powders calcinated under 830 °C, and at least twice those of commercial PZT-4, PZT-5A and PZT-8 ceramics. The improved transduction coefficient is owing to the enhanced piezoelectric constant and spontaneous polarization resulted from the increased grain size, relative density and the fraction of tetragonal phase. These results indicate that this is a simple but effective way to tailor the transduction coefficient in piezoelectric ceramics. 相似文献
87.
《Optical Fiber Technology》2006,12(3):265-267
In this paper, we proposed a high birefringence photonic bandgap fiber (PBGF) with elliptical air holes in cladding and circular air hole in core. The forbidden gaps of the honeycomb structure are calculated when the circular air holes are deformed to the elliptical shape. And the birefringence of the PBGFs is investigated by using a full-vector finite element method (FEM) and the numerical results are presented. 相似文献
88.
设计并实现了一种基于FPGA的四进制连续相位调制器(PCM)。该调制器的基带调制模块通过查表法实现,复杂度较低。仿真结果验证了设计的正确性。 相似文献
89.
空时分组码技术结合信道编码、调制和天线分集技术,当发送天线一定时,他的解码复杂度正比于发送速率,在3G标准中,该技术有着重要的地位。对空时分组码及相关知识进行了介绍,并对可变速率的空时分组码设计进行了探讨,最后展望了空时分组码技术的应用前景。 相似文献
90.