Investigating the Effects of Eichhornia Crassipes Biodiesel and Liquefied Petroleum Gas on the Performance and Emissions of a Dual-Fuel Engine

This study considers the effect of Eichhornia Crassipes Biodiesel(ECB)blends on the performances,combustion,and emission characteristics of a direct injection compression ignition engine operated in a dual-fuel mode(DFM)and equipped with an Exhaust gas recirculation technique(EGR).In particular,a single-cylinder,four-stroke,water-cooled diesel engine was utilized and four modes of fuel operation were considered:mode I,the engine operated with an ordinary diesel fuel;mode II,the engine operated with the addition of 2.4 L/min of lique-fied petroleum gas(LPG)and 20%EGR;mode III,20%ECB with 2.4 L/min LPG and 20%EGR;mode IV,40%ECB with 2.4 L/min LPG and 20%EGR.The operation conditions were constant engine speed(1500 rpm),var-iation of load(25%,50%,75%,and 100%),full load,with a compression ratio of 18,and a time injection of 23°BTDC(Before top died center).With regard to engine emissions,carbon dioxide(CO_(2)),carbon monoxide(CO),hydrocarbons(UHC),and nitrogen oxide(NOX)were measured using a gas analyzer.The smoke opacity was measured using an OPABOX smoke meter.By comparing the results related to the different modes with mode I at full load,the BTE(Brake thermal efficiency)increased by 20.17%,11.45%,and 12.66%with modes II,III,and IV,respectively.In comparison to the results for mode II,the BTE decreased due to the combustion of ECB blends by 7.26%and 6.24%for mode III and mode IV,respectively,at full load.In comparison to mode II,the Brake specific energy consumption(BSEC)increased with the ECB substitution.With ECB blends,there is a noticeable decrease in the CO,CO_(2),and UHC emissions at a partial load.Furthermore,the 20%ECB has no effect on CO emissions at full load.For modes II and IV,the CO_(2)increased by 33.33%and 19%,respectively,while the UHC emissions were reduced by 14.49%for mode III and 26.08%for mode IV.The smoke of mode III was lower by 7.21%,but for mode IV,it was higher by 12.37%.In addition,with mode III and mode IV,the NOx emissions increased by 30.50%and 18.80%,respectively.

铅(Pb)在凤眼莲(Eichhornia Crassipes Solms)体细胞中分布的电镜观察

用10 mg/L和100 mg/L浓度的Pb(NO3)2培养10 d的凤眼莲为实验材料,用透射电镜观察了重金属Pb在其细胞内的分布及造成的结构损伤情况.定位结果显示:在10 mg/L浓度处理的凤眼莲植株中,Pb颗粒主要沉积在根上:根的表面、胞间隙、细胞壁、细胞膜和液泡,没有观察到明显的细胞器超微结构损伤,而在叶细胞中则没有观察到颗粒分布.随处理浓度增大(100 mg/L),Pb在根细胞各细胞组分中明显增多,对细胞的损伤亦加剧,表现为:质体解体和染色质凝集.同时,一部分Pb被运输到茎叶部分,主要分布在叶细胞的细胞膜、液泡内和叶绿体上,而在根和叶的其它细胞器都没有观察到颗粒分布.同时,各Pb处理浓度都没对叶细胞超微结构产生破坏.我们的观察结果证明凤眼莲抗重金属Pb的重要耐性机制是:根对重金属的积累,细胞壁的金属沉淀作用和液泡的区域化作用等.

不同营养条件对凤眼蓝生长及根际微生物群落的影响

以全营养处理为对照,设计缺氮和缺磷2种缺素处理,分析不同营养条件下凤眼蓝〔Eichhornia crassipes(Mart.)Solms〕形态、光合作用、抗氧化系统、氮含量、磷含量及根际微生物群落的变化。结果显示:总体上看,缺氮和缺磷处理可显著抑制凤眼蓝鲜质量、叶数、叶宽、分株数和匍匐茎总长,减弱叶发育,增强根发育,且缺磷处理对植株生长和繁殖的抑制作用更明显;缺氮和缺磷处理可显著抑制凤眼蓝叶片的净光合速率和气孔导度,缺氮处理可显著降低叶片叶绿素相对含量,缺氮处理对凤眼蓝叶片光合作用的抑制效果强于缺磷处理。缺磷处理使凤眼蓝叶片中过氧化氢酶、过氧化物酶和超氧化物歧化酶活性以及丙二醛含量明显上升,而缺氮处理对叶片和根中上述3种酶活性和丙二醛含量总体无明显影响。缺氮和缺磷处理使凤眼蓝叶片中氮、磷含量降低,且氮、磷元素优先分配向根部,缺磷处理引起的磷含量的降幅明显高于缺氮处理引起的氮含量的降幅。缺氮和缺磷处理使凤眼蓝根际微生物群落组成多样性降低,其中氮代谢相关(硝酸盐还原、固氮、氮呼吸和硝酸盐呼吸)微生物的相对丰度显著降低,且在氮元素充足时,缺乏磷元素会降低凤眼蓝根际氮代谢相关微生物的富集。综合研究结果显示:缺氮和缺磷处理均能通过抑制光合作用、限制氮代谢相关微生物富集等方式抑制凤眼蓝生长和繁殖,且缺磷处理对凤眼蓝产生的非生物胁迫更强、对凤眼蓝生长的抑制作用更显著。通过控制凤眼蓝对磷元素的吸收防控凤眼蓝爆发具有较大的应用潜力。

富营养化条件下凤眼莲(Eichhornia crassipes)对不同氮素形态的生理响应

采用水培法研究了在富营养化条件下不同铵态氮与硝态氮比例(100∶0、75∶25、50∶50、25∶75、0∶100)对外来植物凤眼莲(Eichhornia crassipes)生长和生理响应的影响。结果表明,随着培养液中NO3-比例的增加,凤眼莲相对生长速率(RGR)升高,克隆分株数增多,根和叶片的NO3-浓度、硝酸还原酶(NR)活性升高。随NH4+比例的增加,尤其在NH4+∶NO3->1时,叶片NH4+浓度和GS活性变化不显著,而根的NH4+浓度、谷氨酰胺合成酶(GS)活性显著升高。研究结果表明,凤眼莲表现出对硝态氮的偏好性以及对NH4+极强的耐受能力。

水生生态系统中高氯酸盐与铬复合污染的生态毒理效应模拟

【目的】探究ClO_(4)^(−)和Cr^(6+)在复合污染条件下对水生生态系统的生态毒理效应。【方法】构建水生生态系统,分别放入生长状况一致的水葫芦Eichhornia crassipes、隆线溞Daphnia carinata和福寿螺Pomacea canaliculata,使其暴露于不同质量浓度ClO_(4)^(−)和Cr^(6+)及其复合污染的水体中,研究ClO_(4)^(−)和Cr^(6+)在单一和复合条件下对水葫芦、隆线溞和福寿螺的生态毒理效应。【结果】随着暴露时间增加,隆线溞的种群增长呈先上升后下降的趋势。0.02 mg·L^(−1)的Cr^(6+)可促进隆线溞生长,200 mg·L^(−1)的ClO_(4)^(−)和0.20 mg·L^(−1)的Cr^(6+)及复合污染处理均对隆线溞生长起抑制作用。0.02 mg·L^(−1)的Cr^(6+)对福寿螺的生长无明显影响,但单一的ClO_(4)^(−)(20和200 mg·L^(−1))和0.20 mg·L^(−1)的Cr^(6+)及复合污染处理均对福寿螺的生长具有明显的抑制作用。随着水中污染物质量浓度的增加,水葫芦各器官中的ClO_(4)^(−)和Cr^(6+)含量相应增加;相同浓度水平下,水葫芦各器官中ClO_(4)^(−)的含量高低顺序为:叶>茎>根,Cr^(6+)含量的顺序为:根>茎>叶。与水葫芦相比,隆线溞和福寿螺体内的ClO_(4)^(−)含量较低。【结论】ClO_(4)^(−)与Cr^(6+)的单一和复合污染均对水生生态系统中的生物造成了毒害作用。水葫芦对ClO_(4)^(−)和Cr^(6+)均有较强的吸收能力,富集ClO_(4)^(−)的主要器官是叶片、富集Cr^(6+)的主要器官是根部,隆线溞和福寿螺对ClO_(4)^(−)也有一定的吸收,但吸收能力弱于水葫芦。

高温季节池塘种植水葫芦对河蟹生长及水质调控的影响

持续高温往往会造成蟹塘内的伊乐藻等水草衰亡,不利于河蟹的生长发育。为探明高温季节池塘种植水葫芦对河蟹生长及水质调控的影响,对养殖“诺亚1号”河蟹的池塘设置3组不同的水草种植模式,即无草塘补种水葫芦组(EI)、有草塘无处理组(EL)和有草塘补种水葫芦组(EIL)进行了为期3个月的试验,比较各组试验塘的水质、水草长势情况以及河蟹的体质量、产量、残蟹率、回捕率等。试验结果显示:EIL组的伊乐藻保存较好,且在高温季节池塘水温低于其他两组;EI组河蟹的体质量、产量、回捕率显著低于EIL组(P<0.05),残蟹率显著高于EIL组(P<0.05),但EI组各项指标与EL组相比没有显著差异(P>0.05)。水质调控方面,EIL组NH_(4)^(+)-N、NO_(2)^(-)-N、TN、TP等水质指标均优于其他两组;8月份EL组的NH_(4)^(+)-N质量浓度显著低于EI组(P<0.05),9月份以后,EL组的NO_(2)^(-)-N、TN质量浓度均显著高于EI组(P<0.05)。结果表明,高温季节在无草蟹塘适当补种水葫芦对河蟹生长有积极作用,沉水性+浮水性水生植物的组合型水草种植模式可有效提高河蟹产量,改善池塘水质。

云南陆良高原水系凤眼莲潜在分布及其影响因素分析

凤眼莲在云南高原水系的分布严重影响陆良县河道工程整治效果。利用最大熵模型MaxEnt和Arc-GIS软件研究河道湿地凤眼莲群落分布,分析影响凤眼莲生长分布的主导环境因子,并解析特征参数对凤眼莲潜在分布和生态位的影响。结果表明:训练集和验证集的AUC值分别为0.965和0.994,模型预测结果良好。凤眼莲主要分布在陆良水系河道中下游,高适生区面积为24.41km2。最暖季降水量,植被保持土壤肥力钾含量、降水量变异系数和海拔对凤眼莲的分布影响较大。研究结果可为云南省陆良县高原区河道湿地的治理提供科学依据。

水葫芦(Eichhornia crassipes)基质中铜残留对蔬菜生长和食用安全的影响

将修复养殖水体中收获的水葫芦堆置发酵后作为基质材料是资源化利用的新思路,但由于养殖废水中普遍存在重金属如Cu的污染问题,因此资源化利用的关键是重金属对蔬菜生长的影响和食用安全问题.研究结果表明：基质中w（Cu）在0～600 mg·kg-1范围内对萝卜和空心菜的生长没有显著影响,而且其可食部分未超出GB 15199—1994《食品中铜限量卫生标准》中Cu含量的安全限量标准（10.0 mg·kg-1）;但基质中w（Cu）〉600 mg·kg-1时,空心菜根系中w（Cu）偏高（15 mg·kg-1左右）.空心菜可食部分w（Cu）（0.5～4 mg·kg-1）显著高于块根类的萝卜（0.2～1.6 mg·kg-1）;2种蔬菜体内Cu含量与基质中可交换态Cu具有显著相关性.相同条件下,种植块根类萝卜的安全性比须根类空心菜要高.在评估基质中重金属污染对农产品食用安全的风险时,不仅需要考虑基质中重金属含量及其有效性,还要考虑蔬菜种类及其生物学吸收特性.

用凤眼莲(Eichhornia crassipes Solms)去除废水中氮、磷元素的功效及其相关因素的研究

在含Ag^+浓度为0.1～2.0ppm的屠宰废水中,凤眼莲降低N、P元素的效率,随浓度增加而降低;当Ag^+浓度为2ppm时,凤眼莲降低N、P元素的效率,随处理时间的延长而增加。去除N的百分率低于P的百分率。屠宰废水中的Ag^+浓度高达15ppm时,凤眼莲植株在24小时内坏死。不同Ag^+浓度的废水对凤眼莲根系脱氢酶活力水平的影响大小不同,从而影响到N、P元素的去除效率。实验结果为利用凤眼莲净化屠宰废水,富集回收水环境中的银,提供了重要依据。

喀斯特湿地水葫芦(Eichhornia crassipes)生长及表型可塑性特征对不同富营养化水体的响应

选择桂林会仙喀斯特湿地,以不同富营养化水体中生长时期为6月(生长旺盛期)和8月(暴发高峰期)的水葫芦(Eichhornia crassipes)为研究对象,探讨不同富营养化条件下水葫芦的生长及表型可塑性响应特征,以揭示水葫芦对不同富营养化水体的生态适应机制.结果表明:水葫芦的株高、根长和叶绿素含量均随水体富营养化程度的增加而降低,叶柄数、叶柄宽、叶片数、叶长、叶宽、匍匐茎数和分株速率随着水体富营养化程度的增加而升高;各性状参数在暴发高峰期均略高于生长旺盛期;根生物量、茎生物量、叶生物量和总生物量均随水体富营养化程度的加深而增加,茎生物量高于根生物量和叶生物量;水葫芦生物量的分配以及性状间的权衡关系(根生物量比、茎生物量比、叶生物量比和茎叶比等)因生长时期的不同而呈现差异性,表现出较强的表型可塑性特征;水体总有机碳、总氮、总磷、硝态氮、氨氮和叶绿素a浓度分别与水葫芦的茎生物量、叶宽、匍匐茎数和分株速率间存在显著的正相关关系,与根长、株高、叶生物量比和茎叶比间存在显著的负相关关系;水葫芦的表型可塑性指数在0.009~0.792之间,叶重比的可塑性指数最大,根冠比最小,重度富营养化水体下的可塑性指数最大.在会仙喀斯特湿地不同富营养化水体环境中,水葫芦通过外部形态结构调节和生物量的配比关系,产生了有利于其入侵和存活的较强的表型可塑性,是其生存繁殖的重要响应机制之一.

Performance of a water hyacinth(Eichhornia crassipes)system in the treatment of wastewater from a duck farm and the effects of using water hyacinth as duck feed

Nowadays, intensive breeding of poultry and livestock of large scale has made the treatment of its waste and wastewater an urgent environmental issue, which motivated this study. A wetland of 688 mz was constructed on an egg duck farm, and water hyacinth （Eichhornia crassipes） was chosen as an aquatic plant for the wetland and used as food for duck production. The objectives of this study were to test the role of water hyacinth in purifying nutrient-rich wastewater and its effects on the ducks＇ feed intake, egg laying performance and egg quality. This paper shows that the constructed wetland removed as much as 64.44% of chemical oxygen demand （COD）, 21.78% of total nitrogen （TN） and 23.02% of total phosphorus （TP）. Both dissolved oxygen （DO） and the transparency of the wastewater were remarkably improved, with its transparency 2.5 times higher than that of the untreated wastewater. After the ducks were fed with water hyacinth, the average daily feed intake and the egg-laying ratio in the test group were 5.86% and 9.79% higher, respectively, than in the control group; the differences were both significant at the 0.01 probability level. The egg weight in the test group was 2.36% higher than in the control group （P 〈 0.05）, but the feed conversion ratios were almost the same. The eggshell thickness and strength were among the egg qualities significantly increased in ducks fed with water hyacinth. We concluded that a water hyacinth system was effective for purifying wastewater from an intensive duck farm during the water hyacinth growing season, as harvested water hyacinth had an excellent performance as duck feed. We also discussed the limitations of the experiment.

Anatomical studies on water hyacinth (Eichhornia crassipes (Mart.) Solms) under the influence of textile wastewater

Water hyacinth (Eichhornia crassipes (Mart.) Solms) is a prolific free floating aquatic macrohpyte found in tropical and subtropical parts of the earth. The effects of pollutants from textile wastewater on the anatomy of the plant were studied. Water hyacinth exhibits hydrophytic adaptations which include reduced epidermis cells lacking cuticle in most cases, presence of large air spaces (7～50 μm), reduced vascular tissue and absorbing structures. Textile waste significantly affected the size of root cells.The presence of raphide crystals was noted in parenchyma cells of various organs in treated plants.

海州常山(Clerodendrum trichotomum)提取液对凤眼莲(Eichhornia crassipes)生长的抑制作用

研究海州常山(Clerodendrum trichotomum)的2种提取液对入侵性水生杂草凤眼莲(Eichhornia crassipes)叶片的抑制作用,并通过测定凤眼莲叶片的叶绿素含量、过氧化氢酶活性和丙二醛含量分析其抑制机制。结果表明:与空白组和对照组相比,喷施海州常山提取液的凤眼莲健康叶片比例低于1%(P<0.01),死亡叶片比例高于85%(P<0.01),凤眼莲叶片的叶绿素含量显著降低(P<0.05),过氧化氢酶活性显著升高(P<0.05),丙二醛含量极显著增加(P<0.01)。由于海州常山提取液作用于凤眼莲叶片,造成叶片的叶绿素含量降低,活性氧积累,生物膜系统受到损伤,从而导致凤眼莲叶片干枯腐烂甚至衰亡。说明海州常山提取液对凤眼莲的生长具有明显的抑制作用,为生物防治凤眼莲提供了一种新途径。

Biogas Production Using Water Hyacinth (Eicchornia crassipes) for Electricity Generation in Kenya

Water hyacinth, E. crassipes, an invasive water weed thrives in fresh water bodies causing serious environmental problems. In Kenya the weed has invaded Lake Victoria and poses great socioeconomic and environmental challenges. Currently the weed is harvested from the Lake and left in the open to rot and decay leading to loss of aesthetics, land and air pollution. There is therefore need for development of value addition and economic exploitation strategies. The aim of the study is to assess the potential for utilization of the weed as a renewable energy resource for biogas production. Samples were collected from Lake Victoria, pulped and blend with cow dung at a ratio of 3:1 as inoculum. The resultant mixture was mixed with water at a ratio of 1:1 and fed into a 6 m3 tubular digester. The digester was recharged with 20 kg after every three days. The temperature, pH variations, gas compositions, upgrading and gas yields were studied. The temperature ranged between 22.8°C - 36.6°C and pH 7.4 - 8.5. Biogas was found to contain 49% - 53% methane (CH4 ), 30% - 33% carbon dioxide (CO2 ), 5% - 6% nitrogen (N2 ) and traces of hydrogen sulphide (H2S). The biogas was upgraded using solid adsorbents and wet scrubbers increasing the methane content by up to 70% - 76%. The upgraded gas was used to power internal combustion engines coupled with an electricity generator and direct heat applications. The study concludes that E. crassipes is a potential feedstock for biogas production especially in areas where it is abundant.

A NOVEL STEROID FROM EICHHORNIA CRASSIPES

6 -Hydroxy-stigmasta-4,22-diene-3-one 1,a novel steroid, was isolated from the Eichhornia Crassipes.Its structure was deter- mined by ~1H and ^(13)C NMR spectroscopy and further confirmed by authen- tic sample,which was synthesized from stigmasterol 2.

水生植物凤眼莲(Eichhornia crassipes Somls)对含银废水的净化与资源化生态工程的实施方案及其发展前景

本文通过凤眼莲等水生植物对含银废水的净化与资源化的生产性应用试验,提出了工程实施的基本工艺,阐述了该工艺方案的特点和运行控制要求,分析了这一废水净化与资源化生态工程的环境效益和经济效益。这对我国感光材料工业和其它有关行业净化低浓度含银废水,并从中回收白银具有重要的意义。

Regulative effect of aqueous extract of Eichhornia crassipes on the oxygen uptake capacity and motion responses of mice under wet/cool stress

OBJECTIVE To investigate the regulative effect of aqueous extract of Eichhornia crassipes on the oxygen uptake capacity and motion responses of mice under wet/cool stress. METHODS KM mice were randomly divided into normal control group,model control group,Eichhornia crassipes lowdose group(0.5g·kg-1)and high dose group(1.5g·kg-1),then performed intragastric administration for a period of 7d.Wet/cold stressed mice model was established using repeated intermittent(3h·d-1,consecutive 7d)exposure method by placing mice into the exposure box which was covered by ice at the bottom(T<0℃;RH>85%).Oxygen consumption was observed during exposure.Inclined plane method(muscle coordination capacity test)was performed immediately after exposure.60-second video of exhaustive swimming(to calculate swimming speed)was taken 1hafter the last exposure,the exhaustive swimming time was recorded.RESULTS(1)Compared with normal control group,model control group showed significant improvement in oxygen consumption(P<0.01),with an increase up to 77.33%,while inclined plate time,swimming speed and exhaustive swimming time showed significant reduction(P<0.01),at the rates 46.3%,8.54% and 19.68%respectively.(2)Compared with normal control group,Eichhornia crassipes low dose group and high dose group both improved oxygen consumption significantly(P<0.01),at rates of 10.93% and 90.38%respectively.This indicated high-dose aqueous extract of Eichhornia crassipes could fulfil actual oxygen demand of wet/cold stressed mice effectively.Inclined plate and exhaustive swimming experiments indicated that low-dose aqueous extract of Eichhornia crassipes boosted physical power significantly,as its exhaustive swimming time was increased up to 56.61%.Meanwhile,high-dose aqueous extract of Eichhornia crassipes has significant regulative effect on muscle coordination capability and motion speed,which were increased by 17.38% and 11.17%,respectively.CONCLUSION Aqueous extract of Eichhornia crassipes has definite regulative effect on the oxygen uptake capacity and motion responses of wet/cold stressed mice.Aqueous extract of Eichhornia crassipes can achieve stress protective effect by improving oxygen uptake capacity,muscle coordination capacity and motion abilities.

Effects of Eichhornia crassipes Growth on Aquatic Plants in Dianchi Lake

[Objective] The aim was to study the effects of Eichhornia crassipes as an invasive plant on aquatic plants in Dianchi Lake. [Method] Based on the determination of chlorophyll content of phytoplankton and submerged plant (Potamogeton pectinatus) in Dianchi Lake in different months, the effects of E. crassipes on aquatic plants in Dianchi Lake were studied, and the allelopathy effect of root culture solution of E. crassipes on Microcystis aquaticum was discussed. [Result] The growth of E. crassipes in Dianchi Lake reduced the chlorophyll content of phytoplankton and submerged plant (P. pectinatus), and it showed that E. crassipes had certain inhibitory effect on their growth; the culture solution of E. crassipes root inhibited M. aeruginosa growth obviously. [Conclusion] The study could provide scientific references for the prevention and control of ecological safety of E. crassipes.

Establishment and Control of Water Hyacinth(Eichhornia Crassipes) Invasive Species in Aquatic System

This dissertation chiefly examines the functions of water hyacinth and discusses the potential problems associated with invasive species.In general,E.crassipes has significant potential as a source of biomass energy,such as improving physical properties of soil as well as soil structure;additionally,ventilates the soil and brings great conveniences for water penetrating through soil.With regard to the overall research,an amount of significant research has illustrated that water hyacinth can form dense mats that spread out across water surfaces in the end blocking the entire water body.Specifically,water hyacinth would change water clarity and lessening phytoplankton production,dissolved oxygen,nitrogen,phosphorous,heavy metals and concentrations of other pollutants.Relevant studies quoted in this report would gain prominence in further aquatic conservation and maintaining the integrity of ecosystem function since previous research and experience would be highlighted and explored in depth.Although some gaps between theory and experimental evidence still exist,preferable management method combines chemical,mechanical,fire and biological control methods with land management changes.