Impact of climate changes on potential sugarcane yield in Pernambuco,northeastern region of Brazil

Sugarcane is a typical culture of hot and humid climate and therefore is well adapted to the climate in many regions of Brazil. However, there may be yield reductions in the Northeastern region of Brazil due to possible future reductions in rainfall levels. The aim of this study was to simulate, using the Century 4.5 model, the impact of climate changes on potential sugarcane yield in Goiana and Itambé, Zona da Mata of Pernambuco. The Century 4.5 model was booted with soil and climate data from 1950 to 2012. Data on total soil carbon, soil texture (sand, silt and clay contents), pH, soil density and soc stocks were obtained from previous studies. The climate scenario used was the average emissions SRES A1B, designed by Eta/CPTEC model for periods 2014–2040, 2041–2070 and 2071–2100, which is composed of LOW member (low emissions) and HIGH member (high emissions). According to the results obtained by A1B scenario, the potential yield can be reduced in the near future (2014–2040). The high temperatures in northeastern Brazil will increase the evapotranspiration rates, reducing the amount of water available in the soil, making the planting of sugarcane increasingly difficult, which tend to be strongly reduced in drier areas, such as cities located in the western portion of the Zona da Mata region, northern state of Pernambuco, Brazil.     

蔗渣纤维素的分离活化研究进展

纤维素是最丰富的可再生资源,通过醚化、酯化、降解和接枝共聚等反应可制得一系列产品,但蔗渣等天然纤维素原料中的纤维素被木质素包裹和半纤维素缠绕,且自身通过分子间氢键形成晶体结构使得纤维素的可及度小,难以进行反应。为了提高纤维素可及度,必须对原料进行预处理,脱除木质素和半纤维素以及消除部分晶体结构,本文介绍了蔗渣纤维素化学预处理方法的研究进展。     

Characterization of sugarcane bagasse powders

Sugarcane bagasse is a promising renewable lignocellulosic feedstock. Hence, proper characterization of bagasse powders is important for the development of novel technologies based on this resource. In this work, bagasse powders are prepared by sieve fractionation followed by cutting milling and rotor milling (which acts by impact, shear, and friction). The generated powders are characterized by techniques commonly applied to other particulate systems, namely scanning electron microscopy, light scattering particle sizing, and nitrogen adsorption. Particle size distribution, envelope density, specific surface areas, and effective cell wall thickness are determined. Results obtained from different techniques are compared. Finally, the applicability of the analytical techniques to sugarcane bagasse powders is discussed.     

临沧市甘蔗产业发展现状与对策措施

临沧市蔗糖产业经过50多年发展,现已发展成为全市影响面最广、关联度最大的经济支柱产业和云南省最大的蔗糖生产基地。蔗糖产业的发展带动了全市建筑建材业、交通运输业、加工制造业的快速发展,并吸纳了农村大批的剩余劳动力,有力地促进了农村产业结构调整和农业产业化进程。本文总结了全市甘蔗产业发展现状,深入分析存在的主要问题,提出了巩固提升甘蔗产业发展目标和科技保障的措施。     

浅析广西东糖集团五洲蔗区甘蔗蔗糖分偏低的原因及对策

本文通过3年的调研,详细分析了广西东糖集团五洲蔗区甘蔗蔗糖分偏低的原因,即气候偏冷、降雨多、偏施氮肥、砍运安排不当等因素。结合当地实际情况提出：大力推广甘蔗尾茎做种和地膜覆盖,扩大冬植蔗种植面积,采用平衡施肥,同时加强砍运管理等,提高甘蔗蔗糖分。     

过氧化氢漂白稳定剂对漂后蔗渣浆性能的影响

研究了非硅过氧化氢漂白稳定剂（PP-1＋PP-2）对蔗渣压力过氧化氢漂白浆强度性能和纤维形态的影响。研究结果表明：添加0．1％PP-1＋0．5％PP-2的稳定剂后,蔗渣压力过氧化氢漂白浆的白度达到85．0％ISO。与使用硅酸钠的漂后浆相比,非硅稳定剂（PP-1＋PP-2）漂后浆的抗张指数提高了2．6N．m／g,撕裂指数和耐破指数基本相当。（PP-1＋PP-2）作为稳定剂的蔗渣漂后浆的纤维长度、宽度和粗度与Na2SiO3漂后浆的相当,但纤维卷曲指数和细小纤维的含量低于Na2SiO3漂后的蔗渣浆。（P-1＋PP-2）漂后的蔗渣浆与Na2SiO3的漂后浆相比,纸浆的表面电荷和羧基含量较高,而Z电位较低。     

甘蔗高位举升田间运输车的机构设计与分析

田间运输是甘蔗机械收获过程中必不可少的环节。根据甘蔗收获后的田间运输要求,采用分级和同步举升的结构设计方案设计出了田间高位举升运输车的举升与自卸机构,可以满足田间货物转运的要求。机构的受力分析与仿真试验结果表明：各机构的拉杆及油缸在举升的起始位置受力最大,自卸机构的油缸最大推力约为80 kN,拉杆最大拉力约为50 kN;T式同步举升机构的油缸最大推力约为73 kN,拉杆最大拉力约为52 kN;举升臂在运动的5 s过程中,在0.47397 s时刻举升臂受到的最大应力值为200.15 MPa,最大应力位置在举升臂与机架的相连处。文中的研究为进一步设计制造田间高位举升运输车提供了技术基础和理论依据。     

Effect of Saccharomyces cerevisiae and Zymomonas mobilis on the co-fermentation of sweet sorghum bagasse hydrolysates pretreated under varying conditions

Hydrolysates from sweet sorghum bagasse pretreatment normally contains hexose and pentose sugars, and this complex mixture of sugars presents a challenge for a single microorganism to effectively ferment all sugars to ethanol. In this study, synergistic effects on the co-fermentation of the hydrolysates using Sacchromyces cerevisiae and Zymomonas mobilis ATCC31825 at different ratios were studied. An inoculum of mixed cultures (1:3 and 5:10 g/L, Z. mobilis to S. cerevisiae ratios) was investigated. Each mixed culture was added to the hydrolysates at pH 4.8 and incubated 32 °C for 24 h. The mixture of Z. mobilis to S. cerevisiae at 5:10 g/L showed the highest synergistic effect with ethanol yields of 0.5 g/g. Since the yield for co-culture was significantly higher than the sum of yields from each microorganism, the improvements can be directly related to co-fermentation of hydrolysate by S. cerevisiae and Z. mobilis.     

蔗渣模压制品工艺研究

根据蔗渣模压制品的特性与质量的关系，分析了胶量、热压温度、时间和压力对于模压制品各项物理力学性能的影响。对蔗渣模压制品工艺做了系统研究，确定了模压制品较佳工艺参数。