Biodiesel production from rubber seed oil using poly (sodium acrylate) supporting NaOH as a water-resistant catalyst

Poly (sodium acrylate) supporting NaOH (NaOH/NaPAA) was prepared by in situ polymerization of aqueous solution of acrylic acid with an over-neutralization by adding excess of NaOH. NaOH/NaPAA presented a promising selectivity for water absorbency and good water retention with negligible swelling capacity in the organic solvents of methanol, glycerol, rubber seed oil methyl esters, and rubber seed oil. NaOH/NaPAA catalysts showed a basic strength of 15.0 < H_ < 18.4 and their basicity increased with the increase of the NaOH loading amount. NaOH/NaPAA catalysts exhibited almost the same catalytic activity in the transesterification of rubber seed oil with methanol under the optimized reaction conditions compared to conventional homogeneous NaOH catalyst. Furthermore, the functional absorbent/catalyst system presented a good water resistance in the transesterification which retained high catalytic activity when a water concentration in the reaction system was less than 2 wt.%.     

原油微生物群落构成多样性及降解菌DYL-1降解原油的研究

为分离得到高效原油降解菌,直接向原油中加入营养物刺激,培养一段时间后原油乳化降解,傅里叶红外光谱显示,2957cm-1、723cm-1处吸收峰消失;2855cm-1、1377cm-1处吸收峰减弱;880cm-1以及800cm-1吸收峰几乎消失,表明原油发生降解,效果明显。同时分离得到一株降解菌,经分子鉴定为芽孢杆菌属(Bacillus sp.),红外光谱法和紫外吸收法分析表明其具有较强的降解原油烃的能力。根据传统分子生物学的方法,构建原油菌16S rDNA克隆文库,限制性酶切片段长度多态性(Restriction Fragment Length Polymorphism,RFLP)分析了原油中的细菌多样性。结果表明此方法有效地评估了原油中的细菌群落和多样性。     

泰州市奶牛乳房炎调查及其病原菌的分离

奶牛乳房炎是奶牛场的常发病和难以防治的疾病,为进一步了解引起奶牛乳房炎的病原微生物,本研究通过对泰州市3个奶牛场572头泌乳牛的乳房炎发病率进行了调查并对乳房炎主要病原菌进行分离和鉴定。结果表明,奶牛临床型乳房炎的发病率为7.69%,隐性型乳房炎发病率为56.64%,乳区阳性率为33.8%,其中临床型:隐性=1:7.36。从65份确定患有乳房炎的奶样中共分离获得8种细菌、156株分离株,且引起乳房炎的主要病原菌是金黄色葡萄球菌和表皮葡萄球菌,其次是停乳链球菌、大肠杆菌、乳房链球菌和无乳链球菌,其检出率分别为42.31%、23.08%、8.97%、6.41%、5.13%和1.28%。该项调查结果初步明确了泰州市乳房炎发病情况,同时为进一步综合防治奶牛乳房炎和研制乳房炎治疗药物提供了科学依据。     

Metabonomic study of aristolochic acid-induced nephrotoxicity in rats

This paper describes a metabonomic study characterizing the nephrotoxicity induced by aristolochic acid (AA), a suspected kidney toxicant. For these studies, we examined the biochemical compositions of AA-treated rat urine using LC-MS and pattern recognition methods. The biochemical and histological patterns of rat groups treated with different AA sources showed distinct differences from those of the control group. Certain metabolic pathways, such as homocysteine formation and the folate cycle were significantly accelerated, while others, including arachidonic acid biosynthesis, were decreased. A subset-validation procedure using linear discriminant analysis (LDA) and selected predictive variables indicated that approximately 95% of the treated and nontreated rat urine samples were classified correctly into their respective treatment groups. The results suggested that this metabonomic approach is a promising methodology for the rapid in vivo screening of nephrotoxicity associated with ingesting multi-ingredient medicinal herb supplements, and provides a valid method for comprehending the chemical-induced perturbations in the metabolic network and the networked lesions.     

芋侧球茎发生发育的形态学机理

观察了魁芋和多子芋腋芽、侧球茎发生发育的形态学变化规律,分析了主球茎顶芽和不同发育期腋芽中蛋白质的组成。结果表明,魁芋每一叶轮上腋芽数目为１;多子芋为３或３个以上,其中一个体积较大。魁芋侧球茎发育初期伸长的速度大于增粗,首先形成圆柱型,然后顶端膨大形成体积很小的侧球茎。多子芽腋芽伸的同时茎部明显变粗,首先形成圆锥型,然后发育成品种特有的形状。根据发育进程将腋芽发育分成ＡＢ１－ＡＢ９个时期,将主球茎     

生态系统多功能性的指标选择与驱动因子: 研究现状与展望

全球变化和人类活动正以空前的速度在世界范围内改变着生物多样性, 这导致了全球生物多样性的锐减以及生产力的下降、病虫害的增加和抗入侵能力的减弱等生态问题。近30年来, 生态学家开始对于生物多样性的持续丧失是否以及如何影响生态系统功能的问题越来越感兴趣, 生物多样性与生态系统功能(biodiversity and ecosystem functioning, BEF)关系的研究应运而生, 并成为生态学研究的热点之一。但长期以来, 研究者更多地关注单一生态系统功能, 而忽略了生态系统能够同时提供多种生态系统功能的能力, 即生态系统多功能性(ecosystem multifunctionality, EMF)。本文综述了EMF研究中功能指标的选择、生物多样性的不同维度、微生物多样性对EMF的影响以及其他非生物因子对EMF的驱动等进展。因只考虑单一功能可能会低估生物多样性对整体生态系统功能的影响, 故生物多样性与生态系统多功能性(BEMF)关系的研究成为BEF关系研究的重点。近年来, BEMF关系的研究发展较快, 在不同生态系统(包括水生、草地、森林、旱地、农业等)、不同研究尺度(从区域到全球尺度)、BEMF关系的驱动机制(从单一驱动机制到多种驱动机制共同作用)、研究方法(包括新概念以及新的量化方法的提出和应用)等方面均取得了新的进展。但仍有不足之处, 如对于EMF研究中功能指标的选取没有统一的标准、对地下微生物多样性的关注度不够、涉及多营养级水平下的BEMF关系研究较少、驱动EMF的机制仍存在争论等。未来应加强对于功能指标选取的标准研究, 综合分析地上、地下生物多样性以及非生物因子对EMF的整体影响, 加强生态系统多服务性(ecosystem multiserviceability, EMS)方法的研究和应用。     

Compositionally Graded Cathode Material with Long‐Term Cycling Stability for Electric Vehicles Application

Al is introduced into a compositionally graded cathode with average composition of Li[Ni_0.61Co_0.12Mn_0.27]O₂ (FCG61) whose Ni and Mn concentrations are designed to vary continuously within the cathode particle. The Al‐substituted full concentration gradient (Al‐FCG61) cathode is tested for 3000 cycles in a full‐cell, mainly to gauge its viability for daily charge/discharge cycles during the service life of electric vehicles (≈10 years). The Al‐substitution enables the Al‐FCG61 cathode to maintain 84% of its initial capacity even after 3000 cycles. It is demonstrated that the Al‐substitution strengthens the grain boundaries, substantiated by the mechanical strength data, thereby delaying the nucleation of microcracks at the phase boundaries which is shown to be the main reason for the cathode failure during long‐term cycling. It also shows that the Al‐substitution decreases the cation mixing and suppresses the deleterious formation of the secondary phase that likely initiates the microcracks. Unlike an NCA cathode, whose depth of discharge (DOD) must be limited to 60% for long‐term cycling, the proposed Al‐FCG61 cathode is cycled at 100% DOD for 3000 cycles to fully utilize its available capacity for maximum energy density and subsequent reduction in cost of the battery.     

旱作果园深沟施肥对苹果树根系分布的影响

用干挖壕沟法研究了深沟施肥农艺措施对旱作苹果树根系的重量、结构和分布范围等的影响,结果表明,与未挖泡的对照相比,深沟施肥后,根系的总重量、总体积和分布深度都大幅度减少,总重量减少了５０％,总体积减少了６０％,分布深度减小了１．８ｍ;但吸收根的总长度增加,吸收根在总根量中所占的比例亦大幅度提高。