元宝枫油制取生物柴油的工艺优化

通过两步法制取元宝枫生物柴油.第一步采用浓H2SO4催化、甲醇预酯化对元宝枫油进行降酸、脱水处理,使其酸值降至小于1.第二步采用KOH催化、酯交换反应制取生物柴油.对两步法制取生物柴油的工艺条件进行了试验研究,并通过气相色谱分析了生物柴油的脂肪酸中酯组成及含量,同时对生物柴油的性能参数进行了检测.结果表明,第一步工艺条件为:醇油摩尔比6,催化剂质量分数0.6%,反应温度50℃,反应时间90 min;第二步最佳工艺条件为:醇油摩尔比6,催化剂质量分数0.9%,反应温度60℃,反应时间50 min,可使元宝枫油转化率达99%以上.气相色谱分析表明:元宝枫生物柴油中18～20碳脂肪酸甲酯质量分数为91.54%,其中油酸甲酯质量分数为37.03%,亚油酸甲酯质量分数为41.37%.     

超声波辅助下固体酸催化棉籽油制备生物柴油

探讨了超声波辅助条件下采用新型固体酸S2O82-/A l2O3-ZrO2-La2O3替代传统的液体酸、碱催化剂,催化棉籽油与甲醇进行酯交换反应制备生物柴油。考察了超声波频率、功率、固体酸催化剂用量、醇油摩尔比、反应温度等因素对产物中甲酯含量的影响。结果表明,在超声波辅助下,固体酸催化剂对棉籽油酯交换具有较好的催化活性和稳定性,产物与催化剂易于分离。在超声波频率28 Hz、功率80 W、反应温度140℃、醇油摩尔比15∶1、固体酸催化剂用量为油质量的4%的条件下,反应3 h产物中棉籽油甲酯含量达到97.1%,催化剂重复使用十次甲酯含量可维持在90%左右。     

甲醇柴油与生物柴油微粒排放粒径分布特

以石化柴油为参照,在发动机台架上,采用电子低压冲击仪及其附带的两级稀释系统测试了燃用柴油、甲醇柴油和生物柴油排放的不同粒径微粒的数量浓度、体积浓度,分析了发动机转速、负荷以及燃油种类对微粒粒径分布的影响.试验证明:在外特性下,柴油、甲醇柴油排放的微粒数量浓度随转速增大而增加,生物柴油排放的微粒数量浓度随转速没有明显变化规律;在2 300 r/min,生物柴油和柴油随负荷的减小排放的微粒数量浓度增加;标定功率下,柴油排放微粒的体积浓度大于生物柴油和甲醇柴油,但在核模态范围内,相对于柴油,甲醇柴油排放的微粒数量浓度是下降的,降幅达62.8%.生物柴油是上升的,升幅为30.7%.     

柴油机掺烧桐油制备生物柴油的动力性和经济性

在ZX195型直喷式柴油机上进行了桐油制备的生物柴油和石化柴油不同配比的混合燃料试验研究.试验结果表明:在不对柴油机做任何调整的情况下,燃用B10和B20的桐油生物柴油对发动机动力性和经济性影响不大;燃用B50和B100的生物柴油时,动力性和经济性下降明显,其功率下降11%,油耗增加35%左右;综合考虑发动机的动力性和经济性,燃用B20较为合适.     

国内外生物柴油的原料来源及应用现状

能源危机是一个全球化的问题,开发新能源是我国新兴产业发展战略的一项重要规划。来源于动植物油脂的生物柴油具有易于被生物降解、可再生以及类似于石化柴油的动力和燃烧等特性受到专家的关注。本文从生物柴油的生产原料、国内外应用现状、我国生物柴油的发展状况等方面进行了综述,并对我国生物柴油产业化的发展前景进行了展望。     

生物柴油发展现状及其对柴油机的影响

生物柴油是一种可再生、易于生物降解的清洁含氧燃料,具有与石化柴油相近的物化特性,是一种理想的替代能源。详细介绍国内外的生物柴油研究应用现状,分析将其应用到柴油机过程中对柴油机动力性、经济性、排放、噪声、磨损和储存的影响。     

柴油机富氧进气燃用乳化柴油的循环变动与燃烧特性

在直喷柴油机上采用进气增氧(氧气在进气中的体积分数为21%、23%、25%和30%)技术,对燃用不同掺水乳化柴油(水在乳化柴油中的体积分数为0%、10%、20%和30%)的循环变动及燃烧特性进行研究;实验工况为发动机经济转速、中等负荷,采集20个连续循环,取最大爆发压力值,计算循环变动率.研究结果表明:在纯柴油条件下,随氧含量的增加,缸内最大爆发压力增加,循环变动率降低,燃烧始点提前;在使用乳化柴油时,着火点随水乳化率的增加而推后,但其依然遵循随进气O2体积分数增加而提前的规律;含水率达30%时,着火延迟加大,燃烧组织恶化,循环变动加大.     

生物质热解生物油/柴油乳化燃料的制备与试验

制备了生物油/柴油乳化燃料并在柴油机台架上进行了试验.试验用生物油是在流化床反应器上对玉米秸秆粉进行热解试验获得的.将生物油与0号柴油以及适量的乳化剂混合,通过均质机均质,得到生物油/柴油乳化燃料.在ZS1110型柴油机台架上进行两种不同配比的生物油/柴油乳化燃料的发动机台架试验,得出了柴油机燃用生物油/柴油乳化燃料和纯柴油的负荷特性和排放特性曲线,并且对乳化燃料和纯柴油的油耗率和有效热效率进行了对比.研究结果表明:生物油体积分数为15%的生物油/柴油乳化燃料较纯柴油有明显的节油效果,最大节油率可达10%;NO、CO的排放也优于纯柴油的排放.     

生物油/柴油乳化燃料的燃烧特性

为了研究生物油/柴油乳化燃料的燃烧特性,利用非离子表面活性剂复配,对热解生物油/柴油混合液进行了乳化,测量了乳化燃料的密度、热值、动力黏度及pH值。在SD1110型柴油机台架上进行4种不同配比的生物油/柴油乳化燃料的发动机台架试验,得出了柴油机燃用生物油/柴油乳化燃料和纯柴油的负荷特性和排放特性曲线,并且对乳化燃料和纯柴油的排放特性进行了对比。研究结果表明：生物油体积分数为20%的乳化燃料当量油耗率最低,乳化燃料CO的排放高于柴油的排放,且生物油含量越高CO排放越大,而乳化燃料的NO及碳烟的排放则优于纯柴油的排放。由于生物油/柴油乳化燃料的理化特性与柴油接近,可以作为普通柴油机的燃油使用。     

柴油机富氧进气燃用乳化柴油的循环变动与燃烧特性

在直喷柴油机上采用进气增氧（氧气在进气中的体积分数为21%、23%、25%和30%）技术,对燃用不同掺水比乳化柴油（水在乳化柴油中的体积分数为0％、10％、20％和30％）的循环变动及燃烧特性进行研究;实验工况为发动机经济转速、中等负荷,采集20个连续循环,取最大爆发压力值,计算循环变动率。研究结果表明：在纯柴油条件下,随氧含量的增加,缸内最大爆发压力增加,循环变动率降低,燃烧始点提前;在使用乳化柴油时,着火点随水乳化率的增加而推后,但其依然遵循随进气O2体积分数增加而提前的规律;含水率达30%时,着火延迟加大,燃烧组织恶化,循环变动加大。     

Effect of timing of first and last irrigation on the yield and water use efficiency in cotton

With increasing concern about declining water resources, there is increasing thrust in improving water management in farming systems to improve water use efficiency. The present investigation was undertaken to determine the optimum timing for the first and last irrigation of cotton on the basis of meteorological approach for scheduling irrigations. The experiment was conducted in a split plot design with three timings of first irrigation as main-plots and three timing of last irrigation as sub-plots. Delay of first irrigation from 28 days after sowing (DAS) to 42 DAS, irrespective of last irrigation, resulted in an increase of 8, 14 and 17% in seed cotton yield during first, second and third year, respectively. The corresponding increases due to delay in the last irrigation from 130 to 170 DAS were 14, 32 and 8%, respectively. On the basis of 3 years average, application of first and last irrigation at optimum time (after 42 and 170 days after sowing) resulted in an increase of 36% in seed cotton yield without involving any additional cost. Water expense efficiency (WEE) increased by 54%.     

棉籽油作为S195柴油机燃料的试验研究

通过试验研究了S195柴油机燃烧棉籽油与0#柴油的混合燃油时不同喷油压力下喷雾锥角的变化趋势,以及在不同负荷下的有效耗油率.分析可知:适当地提高喷油压力可以改善混合油的燃烧性能;在S195柴油机上燃烧B20混合燃油(由20%的棉籽油和80%的0#柴油组成)时,具有更好的动力性、经济性,为在低速农用柴油机上燃烧棉籽油提供了一个参考依据.     

沙棘籽油对牛的皮肤伤口愈合疗效的研究

本研究旨在通过比较沙棘籽油（Hippophae rhamnoides）和防腐软膏（5％碘伏）、草本软膏（印度草药研究与供应有限公司）及一种刺激性温和的基础药膏（液体石蜡）,来研究沙棘籽油对牛的皮肤伤口愈合效果。这个实验是将12头雄性牛犊分为4组,6头牛都有皮肤伤口,3头胸背部脊椎区的两边都用当地的镇痛药。伤口分别用液体石蜡、5％的碘伏软膏、沙棘籽油（沙棘油）及草本软膏处理28d,并分为Ⅰ、Ⅱ、Ⅲ、Ⅳ四组。不同处理的功效是建立在对经过0d、3d、7d、10d、14d和28d的不同临床血液参数的研究基础之上的。在研究中,所有组的心脏、呼吸率和血液学的各种参数及肛温都维持在正常的生理极限内。沙棘油和草本软膏对伤口处理的临床研究中发现,在伤口愈合的初期,伤口保持了一定的干燥度,并且抑制了炎症初期伤口的恶化。不同的组之间,在持续28d的实验中,用草本软膏和沙棘油做处理的组中伤口的愈合率最高。这些组的伤口试验同时还表现出早治疗,早治愈的特征。但是,在草本软膏和沙棘油处理组中,草本软膏组处理的伤口的整体愈合能力还是略优于沙棘油的疗效。     

沙棘油对犬科动物(狗)消炎能力的评估

用沙棘种子油对狗(12只，性别随机)的急性消炎能力进行了研究。急性炎症试验部位都选择在狗的背部。使用游标卡尺连续7d测量皮肤上发炎部位的情况来检测沙棘种子油的消炎能力。结果说明沙棘种子油有抗炎的能力。同时使用棉球肉芽肿瘤测定法测定了沙棘种子油对狗(12只)皮肤的慢急性炎症的消炎能力。沙棘油对狗皮肤慢性炎症的抗感染能力太弱以致于无法检测到。     

不同灌水量对盆栽棉花产量和品质的影响

在盆栽条件下,以华杂棉H318为试验材料,参照自然蒸发量,设置5个灌溉比例,研究不同灌水量对棉花产量、品质及水分利用效率的影响。结果表明,随灌水量增加,成铃率和单株铃数增加,籽棉产量上升,水分利用效率呈先升后降的趋势。不同灌水量对棉花的纤维品质影响不大,马克隆值随灌水量的增加而降低。综合考虑棉花的产量、品质以及水分利用效率,灌水量80%为最佳的灌水比例。     

茶叶籽油甲酯化制备生物柴油的反应动力学研究

在醇油摩尔比为9∶1、催化剂氢氧化钾用量占油重1.0%的条件下,研究了60℃和70℃下茶叶籽油甲酯化制备生物柴油的反应动力学,采用Origin软件拟合曲线方程,建立了茶叶籽油甲酯化反应的宏观动力学模型。研究结果表明:茶叶籽油甲酯化反应为1.3级反应,活化能为29.22KJ·mol-1·K-1,频率因子为2.5×104mol·L-1·min-1。      

Response of normally sown and paired sown cotton to various quantities of water applied through drip system

The field experiments were conducted for 2 years to evaluate the response of normally sown and paired sown cotton in terms of seed cotton yield and water use efficiency (WUE) at various levels of water applied through drip system. Drip irrigation under normal sowing resulted in an increase in seed cotton yield of 14 and 32% during first and second year, respectively, when same quantity of water was applied through drip and check-basin. Drip irrigation under dense paired sowing, in which the quantity of water applied was 75% as compared to drip under normal sowing, produced equal seed cotton yield during first year but yield increase of 27% was observed during second year. Drip irrigation under normal paired sowing, in which the quantity of water applied was 50% as compared with drip under normal sowing, resulted in a reduction in seed cotton yield of 11 and 15% than normal sowing during first and second year, respectively. However, at equal levels of water applied, dense paired sowing produced 12 and 23% higher seed cotton yield than normal sowing during first and second year, respectively. Similarly, normal paired sowing produced 6 and 14% higher seed cotton yield than normal sowing during first and second year, respectively, The present study revealed that dense paired sowing produced highest yield and water use efficiency along with reduction in cost owing to lower number of laterals required.     

棉籽制油蒸炒工艺的自动控制与研究

介绍一种棉籽制油自动控制系统以及用于制油工艺中的检测和控制方法。在加工过程中，它可以自动调节给水量和蒸炒温度这两个重要参数，使棉籽饼内的残油率有明显降低，同时节能效果也很显著。     

Water status response of corn and cotton to altered irrigation

Water is a primary limiting factor to crop production and thus crop water status is essential information for management decisions. Corn and cotton were grown in the field under two constant water regimes. The low water level (WL) was 0.662PET (potential evapotranspiration) in corn and rainfall for cotton. The high water level (WH) was 1.02PET for both crops. Two transient water treatments in each crop began as the two constant water level treatments but then the water inputs were reversed and the change in water status was monitored. When the transient water treatments were initiated, corn was at the V14 and V16 growth stages in the WL and WH treatments, respectively, and cotton was 2 weeks past first bloom for both water levels. The purpose of the experiment was to compare the sensitivity of leaf water potential (LWP) and crop canopy temperature to changes in irrigation rate. The transient water treatment of each crop that relieved water stress (TLH) changed from WL to WH and the treatment which induced water stress changed from WH to WL (THL). The LWP values of the transient water treatments reversed 5 and 8 days after reversing water input rates to corn in 1998 and 1999, respectively, and after 3 days in both years for cotton. A reversal in canopy temperatures, expressed as the amount of daily time that the temperature was above 28°C (DST), was not detected between the TLH and THL treatments of corn after 25 days in 1998 or after 13 days in 1999. The DST values of the cotton transient water treatments reversed after 4 days in 1998 and 5 days in 1999, when the values of THL became greater than for TLH. Corn tassels, which apparently transpire less than leaves, were forming at the beginning of the transient water treatments and their presence in the view of the infrared thermocouples may have reduced the apparent radiometric temperature difference between the transient water treatments. During the water status adjustment period following the initiation of the transient water treatments, there were significant linear relationships between LWP and DST in cotton in both years but only in 1998 in corn. Cotton canopy temperature could be used to rapidly monitor an entire field in contrast to LWP which accurately measures plant water status but cannot provide automated measurements across a large area.     

光电式籽棉质量流量传感器的试验研究

针对籽棉在管道中的输送过程,设计了一种光电式籽棉质量流量传感器,以实现籽棉质量流量的检测。在籽棉质量流量试验台上对该传感器进行了测试与研究,确定了籽棉质量流量和光电传感器输出信号的关系,发现二者的有非常良好的线性关系,并对二者进行了线性拟合,拟合度R2=0.99,表明该传感器是非常具有潜力的。