大豆中粗蛋白质含量不确定度的评估

通过对凯氏定氮仪测定大豆中粗蛋白质含量的检验过程进行分析,找出影响测量不确定度的因素,对各个不确定度分量进行评估和计算合成,并最终给出样品中粗蛋白质含量的合成标准不确定度及扩展不确定度。     

植物组织培养在藏药材研究中的应用

在藏药工业化生产的大环境下，对部分需求量较大和濒危野生藏药材进行人工培育和种植，建立大规模的栽培基地和资源保护基地已迫在眉睫。本文试图从植物组织培养角度研究其人工培育和种植技术，并为其提供理论依据。     

On the density of stabilizable plants in the class of unstabilizable plants: The real symmetric disk algebra case

Let A_R denote the set of functions from the disk algebra having real Fourier coefficients. Generalizing a result of Quadrat we show that every unstabilizable multi-input multi-output plant is as close as we want to a stabilizable multi-input multi-output plant in the product topology.     

原油供应链网络竞合博弈研究

针对原油供应链网络中多条供应链竞合方式选择日趋复杂的现象,通过分析原油供应链网络中多条供应链的竞合特征、影响因素、表现方式等规律,发现原油供应链网络中企业存在的竞合问题。运用博弈论理论方法对供应链网络中链内企业纵向竞合和链际企业横向竞合进行建模分析,结果表明链内企业只受利益因素影响时多采取竞争方式,受风险等其他因素影响时采取合作方式,而链际企业采用以合作为主的竞合方式可以很好地分配企业的市场份额,降低炼化企业采购成本,从而保证原油供应链网络达到多赢的状态。     

Changes in freshwater sediment microbial populations during fermentation of crude glycerol

BackgroundThis work studied how the exposure to an unusual substrate forced a change in microbial populations during anaerobic fermentation of crude glycerol, a by-product of biodiesel production, with freshwater sediment used as an inoculum.ResultsThe microbial associations almost completely (99.9%) utilized the glycerol contained in crude glycerol 6 g L⁻¹ within four days, releasing gases, organic acids (acetic, butyric) and alcohols (ethanol, n-butanol) under anaerobic conditions. In comparison with control medium without glycerol, adding crude glycerol to the medium increased the amount of ethanol and n-butanol production and it was not significantly affected by incubation temperature (28 °C or 37 °C), nor incubation time (4 or 8 d), but it resulted in reduced amount of butyric acid. Higher volume of gas was produced at 37 °C despite the fact that the overall bacterial count was smaller than the one measured at 20 °C. Main microbial phyla of the inoculum were Actinobacteria, Proteobacteria and Firmicutes. During fermentation, significant changes were observed and Firmicutes, especially Clostridium spp., began to dominate, and the number of Actinobacteria and Gammaproteobacteria decreased accordingly. Concentration of Archaea decreased, especially in medium with crude glycerol. These changes were confirmed both by culturing and culture-independent (concentration of 16S rDNA) methods.ConclusionsCrude glycerol led to the adaptation of freshwater sediment microbial populations to this substrate. Changes of microbial community were a result of a community adaptation to a new source of carbon.How to cite: Paiders M, Nikolajeva V, Makarenkova G, et al. Changes in freshwater sediment microbial populations during fermentation of crude glycerol. Electron J Biotechnol 2021;49. https://doi.org/10.1016/j.ejbt.2020.10.007     

原油脱硫化氢方法的改进和优化

原油中硫化氢的脱除具有及其重要的意义,本文采用了安全易行的载气法,利用氮气吹脱除去原油中的硫化氢气体,优化了工艺条件,找出载气的最佳流速为0.15～0.25L/min。与传统真空法相比,含硫化氢量较高的原油中硫化氢的脱除效率明显提高。在碘量法测定硫含量的实验中采取了多项措施以减小实验误差。     

龙脷叶提取物体外抑菌活性初步研究

采用连续二倍梯度琼脂稀释法研究龙脷叶水提物和的50%、70%、95%乙醇提取物的抑菌活性,并对抑菌作用强的提取物以石油醚、乙酸乙酯、正丁醇依次萃取,测定不同极性部位的最低抑菌浓度(MIC)。结果表明,龙脷叶50%乙醇提取物的正丁醇部位对六种试验菌株明显抑制:对金黄色葡萄球菌(Staphylococcus aureus)、金黄色葡萄球菌耐药株(Methicillin resistant Staphylococcus aureus)和大肠杆菌(Escherichia coli)的MIC为15.60m g·mL-1;对铜绿假单胞菌(Pseudomonas aeruginosa)、伤寒沙门氏菌(Salmonella typhi.)和乙型副伤寒沙门氏菌(Bacillus paratyphosus B)的MIC为7.81m g·mL-1。可为进一步研究龙脷叶抑菌活性成分提供依据。     

调整种植业结构发展经济作物

从西藏种植业的基本现状，发展经济作物生产的有利条件及存在问题，谈西藏种植业结构调整的目标和对策。     

苍术属药用植物的研究

  Genus Atractylodes (Fam. Compositae) is the main  source of two important Chinese traditional drugs, “Baizhu”and “Cangzhu”,  both being long used as a stomachic.      After a general survey and taxonomical study, it has been found that “Baizhu” was only derived from A. macrocephala Koidz. (A. ovata auct. Fl. Orient. Asiat. non A. P. DC.), while “Cangzhu” were mainly from A. lancea (Thunb.) DC. and A. lancea DC. var. chinensis Kitam.      Comparison of the components in the rhizomes of Chinese Atractylodes  has been made by TLC and GLC.  The results have shown to be in accordance with their mor- phological features and pharmaceutical merits.      “Baizhu”, A. macrocephala, with its leave pinnately incised, is characterized by the presence of rich atractylon and absence or lack of atractylodin.  As for “Cangzhu”, A. lancea and A. lancea var. chinensis with their leave not incised or only lobed, are cha- racterized by high contents of atractylodin, β-eudesmol and hinesol, but poor in atrac- tylon.      The above conclusion may be of value to both the classification and utilization of this group of Chinese medicinal plants.       

重庆地区能源植物的开发利用

植物能源是一种经济环保的可再生能源,发展植物能源是解决能源危机可行措施。对国内外能源植物的开发利用现状及植物能源的优势进行了概括。重庆地区植物资源非常丰富,文章列举了一些适合重庆地区种植的、应用前景广阔的能源植物种类,并就重庆地区能源植物的开发及利用提出建议。     

政治风险对原油供应链战略联盟作用机理研究

政治风险是影响原油供应链战略联盟持续稳定的最关键的因素。原油供应链战略联盟跨国经营面临的政治风险主要有:政策易变性、非直接征收、东道国局势、局部战争和第三方势力。本文在阐述原油供应链战略联盟特征基础上,运用比较分析法,深入剖析各个政治风险对原油供应链战略联稳定性的影响机理,进而提出原油供应链战略联盟应对政治风险的策略,旨在推动我国原油供应链战略联盟的持续稳定发展。     

高效液相色谱法测定饲料中色氨酸含量

样品用淀粉－氢氧化钡溶液１１０℃封管水解２４ｈ水解物用４ｍｏｌ／ＬＨＣｌ溶液调节ｐＨ至５～６以含１５％甲醇的０．０２ｍｏｌ／ＬＮａＡｃ缓冲溶液（ｐＨ＝４．５）为流动相,经高效液相色谱Ｃ１８柱分离,ＵＶ２８０ｎｍ检测,测定了饲料样品中色氨酸含量,方法简便,重现性好,回收率在９７．７％～１０４．１％之间。