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91.
Forms and solubility of plant nutrient elements in tropical plant waste biochars 总被引:2,自引:0,他引:2
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Thailand is an agriculture‐based country which produces large amounts of agricultural waste. Making biochar from this waste can reduce pollution, decrease costs of production, and increase C sequestration. The agronomic benefits of biochar are partly derived from the available plant nutrients in biochar. This study investigated the fertilizer value of biochars manufactured by slow pyrolysis. Pyrolysis temperature and feedstock type affect nutrient concentrations and nutrient element speciation in biochar. The physio‐chemical, mineralogical and structural properties of biochars made from 14 agriculture wastes (soybean cake, corncob, lemon peel, sugar palm fibre, durian shell, tamarind wood, coconut fibre, coconut shell, bamboo wood, rice husk, eucalyptus wood, oil palm fruit, coffee waste, and bagasse) were investigated. The plant nutrients in biochar mostly occurred in crystalline minerals which were present on the surface and inside the cell structure of biochar. Most biochars examined in this research contained calcite (CaCO3). The presence in biochars of several K‐minerals [archerite (KH2PO4), chlorocalcite (KCaCl3), kalicinite (KHCO3), pyrocoproite (K2MgP2O7), struvite‐K (KMgPO4 · 6 H2O), and sylvite (KCl)] encourages the use of biochar as a K‐fertilizer. Fibre, fruit and wood biochars contained considerable amounts of K, Ca, and P. Sugar palm and coconut fibres also contained high level of Na in halite. This study recommends the utilization of biochars manufactured from sugar palm fibre, coconut fibre, durian shell, and oil palm fruit as fertilizers. With their appreciable contents of plant nutrients in highly to moderately soluble compounds these biochars should be effective fertilizers, especially for use by organic farmers who cannot use any chemical fertilizers. 相似文献
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One pair of near isonegic yellow/black seeded rape (Brassica napus L) were used as experimental materials to study the changes of lignin contents and enzymes activities of 4-coumarate: CoA ligase (4CL), Cinnamyl alcohol dehydrogenase (CAD) and ferulate 5-hydroxylase (F5H) in seedcoats during the stage of seed development. The variation analysis showed that the changes of lignin contents and enzyme activities of 4CL, CAD and F5H in seed coat had significant differences between black- and yellow-seeded rapes, and also between different development stages. The correlation analysis demonstrated that the lignin contents were positively correlative to the activities of all three enzymes investigated in the study, and the interactions between them in the seed coat of the two lines. For yellow-seeded rape, the correlation coefficient (0.7262018) of lignin content and the interaction between 4CL and F5H was significant, the lignin contents were highly positively correlative to the activities of CAD and F5H, the interaction between 4CL and CAD, and the interaction between CAD and F5H. For the black-seeded rape, only the lignin content was highly positively correlative to the activity of F5H (the correlation coefficient was 0.772949), the other correlation coefficients, i. e. lignin contents to 4CL, CAD activities, the interactions between the three enzymes were not significant although all the correlation coefficients were above 0.5000. The results suggested that 4CL, CAD and F5H regulated the biosynthesis of lignin in seedcoat of rapes,leading to the lignin contents in the seedcoats of the yellow-seeded rape much lower than that of the black-seeded line,and affecting the thickness of the developing seedcoats in rapes. Therefore, it was likely to change the seedcoat ratio by overexpressing or suppressing the activities of one of the enzymes, both of them or all of them. 相似文献
94.
萝卜贮藏期间木质素含量变化与糠心的关系 总被引:4,自引:0,他引:4
对3 个红皮萝卜品种贮藏过程中肉质根不同部位木质素平均含量及糠心指数变化进行了研究。结果表明, 随着贮藏时间的延长, 糠心指数和不同部位木质素平均含量均增加; 木质素平均含量在贮藏后30 d 发生显著变化, 贮藏后50 d 达到极显著水平; 根皮部木质素含量变化较小, 且显著低于其它3 个部位; 糠心指数在贮藏后40 d 发生显著变化, 贮藏后50 d 达到极显著水平, 品种间不存在差异。通过回归分析得出, 根皮部木质素平均含量与糠心指数呈显著相关, 根头部、根中部和根下部木质素含量与糠心指数呈极显著相关。 相似文献
95.
以N,N-二环己基碳二亚胺(DCC)为缩水剂,合成了目标化合物1,2-O-异丙叉基-3,5-O-二肉桂酰基-α-D-呋喃木糖,其结构经红外光谱(IR)、核磁氢谱(1H NMR)、核磁碳谱(13C NMR)和质谱(MS)等方法得到了确证;对其300、600、900℃的热裂解成分进行GC/MS分析,并对该目标化合物进行卷烟加香试验,结果表明,该化合物热裂解可得到51种有香味的醛、酮、酸、酯类化合物;该化合物添加量为0.01%时,可以改善卷烟香气质,增加香气量,降低刺激性,改善余味。 相似文献
96.
Sawdust, coal gangue and paper sludge were chosen as pore-forming agents of sintered shale brick. The pyrolysis behaviors of different forming agents were studied and the influences of the agents on bulk density, compressive strength, porosity, and water absorption properties of the shale brick were also investigated. It is shown that, with the increase of the dosage of sawdust, pore number of the sintered bricks and water-absorption increase, while the volume density and strength fall rapidly. Thus, the dosage of sawdust should be controlled within 6%. Because of poorer plasticity and lower ignition of coal gangue as well as low porosity rate of sintered bricks, the water-absorption of sintered bricks is poor, and decreases of density and strength are not obvious. In practical production, according to the requirements of brick-making heat and plasticity, a moderate amount of coal gangue can be added. The plasticity of the bricks improves as the dosage of paper sludge increases due to its good plasticity. However, excessive dosage of paper sludge will result in large shrinkage of sintered brick, low strength and high water absorption; therefore, the dosage should not exceed 7%. 相似文献
97.
利用裂解气相—色谱质谱联用(Py-GC/MS)对卷烟燃烧过程进行模拟,研究枸杞多糖在无氧条件下的热裂解,以期为枸杞多糖在卷烟中的应用提供一些理论基础。用GC-MS定性定量测定分析热裂解产物。比较了不同温度(300,600,900℃)下的裂解产物差异,对裂解产物进行了归类分析,并分析了主要裂解产物致香成分的致香效果,为卷烟评吸提供了理论依据。 相似文献
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傅里叶变换红外光谱是灵敏度高、波数准确、重复性好,用以确定分子组成和结构的定性和定量分析技术。主要对傅里叶红外光谱技术在生物质固体燃料、生物质热解、生物质液化等研究中的应用进行分析和阐述,介绍了傅里叶变换红外光谱及其联合分析技术的应用。 相似文献