不同用量纳米材料对生菜种子发芽的影响

以意大利生菜和红脆香生菜种子为试验材料,研究不同用量石墨相氮化碳纳米材料(0、50、100、150、200 mg/L)对2种生菜种子萌发的影响。结果表明:纳米材料用量在50～150 mg/L时对2种生菜发芽势、发芽率、发芽指数均有促进作用,用量在100 mg/L时,意大利生菜的发芽率、发芽指数最高;用量在150 mg/L时,红脆香生菜发芽势、发芽率、发芽指数最高。纳米材料用量达到200 mg/L时,对生菜种子萌发的促进效果减小,甚至出现抑制萌发的现象。较高用量(150、200 mg/L)的纳米材料可以促进生菜胚根的伸长,用量在150 mg/L时,意大利生菜胚根最长,比对照(CK)增加了24.80%;用量在200 mg/L时,红脆香生菜胚根最长,比对照增加了37.20%。施加纳米材料对生菜胚芽长度的影响不显著。总之,纳米材料用量在50～150 mg/L时,可以促进生菜种子的萌发;较高用量(150、200 mg/L)的纳米材料可以促进生菜种子胚根的伸长;施加纳米材料对胚芽长的影响不显著。     

Time-course comparison of pulmonary inflammation induced by intratracheal instillation of four different nickel oxide nanoparticles in male Fischer rats

Occupational exposure to nickel oxide (NiO) is an important cause of respiratory tract cancer. Toxicity is known to be associated with the dissociated component, i.e. nickel (II) ions. To address the relationship between physicochemical properties, including solubility in artificial lysosomal fluid, of NiO and time-course changes in the pulmonary response, we conducted an intratracheal instillation study in male Fischer rats using four different well-characterized NiO products, US3352 (NiO A), NovaWireNi01 (NiO B), I small particle (NiO C), and 637130 (NiO D). The NiOs were suspended in purified water and instilled once intratracheally into male F344 rats (12 weeks old) at 0 (vehicle control), 0.67, 2, and 6 mg/kg body weight. The animals were euthanized on days 3, 28, or 91 after instillation, and blood analysis, bronchoalveolar lavage fluid (BALF) testing, and histopathological examination were performed. The most soluble product, NiO B, caused the most severe systemic toxicity, leading to a high mortality rate, but the response was transient and surviving animals recovered. The second-most-soluble material, NiO D, and the third, NiO A, caused evident pulmonary inflammation, and the responses persisted for at least 91 days with collagen proliferation. In contrast, NiO C induced barely detectable inflammation in the BALF examination, and no marked changes were noted on histopathology. These results indicate that the early phase toxic potential of NiO products, but not the persistence of pulmonary inflammation, is associated with their solubility.     

应用碳纳米管提高SBS改性沥青及其混合料路用性能的研究

通过向SBS（苯乙烯-丁二烯-苯乙烯三嵌段共聚物）改性橡胶粉末中添加功能纳米材料——碳纳米管的方式,获得了新型的碳纳米管-聚合物复合沥青改性剂.用该复合改性剂与基质沥青制备新型SBS改性沥青.针对改性沥青及其混合料进行大量的结构研究和路用性能测试.包括三大指标试验、差示扫描量热分析（DSC）、显微镜下的微观结构分析以及马歇尔实验.结果表明,由于碳纳米管较大的比表面积及大的π电子结构,能够提高SBS与沥青之间的物理溶胀及弱化学相互作用（这里主要以π-π堆积作用为主）.加入碳纳米管的SBS沥青较单纯SBS改性沥青在综合性能上有较大改观.     

喷施不同纳米材料对水稻幼苗磷含量的影响

为探究喷施不同纳米材料对水稻幼苗生物量和磷含量的影响,将水稻幼苗培养在不同含磷浓度营养液中,对水稻幼苗叶片喷施不同浓度的不同纳米材料,即粒径40 nm的羟基磷灰石(nHA)、三氧化二铁(nFe2O3)、零价铁(nFe)、二氧化铈(nCeO2)和甲壳素[CH,(C8H13NO5)n]悬浊液,测定水稻地上部和根部含磷量。结果表明:在正常供磷条件下,喷施nHA、nFe2O3、nFe处理,浓度分别在200、100 mg·L^-1和150 mg·L^-1时,地上部生物量达到最大,根部生物量则在150、100 mg·L^-1和100 mg·L^-1处理时达到最高;但大部分处理不会显著提高水稻幼苗磷含量。在供磷1/2条件下,各处理均可不同程度促进水稻幼苗对磷的吸收;喷施nHA、nFe2O3、nFe、nCeO2和CH处理,分别在50、100、100、100 mg·L^-1和150 mg·L^-1的浓度处理时生物量达到最大;nHA、nFe2O3、nFe处理均可显著促进地上部磷含量,地上部磷含量分别在150、100 mg·L^-1和150 mg·L^-1处理时达到最高。研究表明:在不同浓度磷供应条件下,喷施粒径40 nm的nHA、nFe2O3、nFe、nCeO2和CH均可不同程度促进水稻幼苗生长。不缺磷条件下,nHA、nFe处理促进生物量增加明显;缺磷条件下,nHA、nFe2O3、nFe促进磷吸收效果更明显。     

纳米材料与技术在农业上的应用研究进展

近几年纳米材料与技术在农业领域的应用取得了一定进展,综述了纳米材料与技术在农业投入品的传输、动植物遗传育种、农产品加工、农业环境改良和农业纳米检测技术等方面的应用。目前纳米技术在农业中的应用研究仍处于初期阶段,一些研究成果实现商业化还需要更大的努力。此外,纳米材料因其特性可能存在潜在的安全性问题,选择生物安全型、环境友好型纳米材料进行农业应用研究对于发展农业纳米技术至关重要。     

纳米材料在鲤鱼养殖中的试验研究

研究了纳米材料对鱼苗生长和对水体理化性状的影响。结果表明,几种纳米材料处理水体均可提高鱼苗成活率,改善水质,其中纳米网的效果最佳,鱼的成活率可提高1倍;纳米材料可提高水体pH,降低NO2-和NO3-含量,其中NO2-降幅最大,为对照组的1/4。     

Amperometric Biosensor Approaches for Quantification of Indole 3-Acetic Acid in Plant Stress Responses

Amperometric biosensors are known to be sensitive, reliable, and inexpensive instruments for biomolecular detection. Recently, self-referencing amperometric biosensors have been utilized to quantify the endogenous apoplastic flux of plant hormone indole 3-acetic acid (IAA) in vivo. There is still a significant need for sampling and testing methods to measure IAA concentrations in whole tissue samples. In the present study we used nanomaterial-modified platinum microelectrodes for the detection of IAA extracted from whole plant tissues. The key to the use of the nanomaterials was to enhance the surface area and thus the limit of detection for IAA. The nanoscale electrochemical interface was modified by the application of a layer of platinum black, followed by silanization overnight and a coating of multiwalled carbon nanotubes. Electroanalytical characterization of sensor performance was evaluated using both IAA standards and IAA extracted from corn plant samples, using a three-electrode scheme (reference, sensing, and auxillary). We compared tissue concentrations in water- and salt-stressed corn seedlings and compared these results to values measured using established enzyme-linked immunosorbent assay (ELISA) protocols. We found that the values obtained from both methods were comparable. The data obtained from the IAA sensor suggested that the electroanalytical biosensor approach was slightly more reliable and sensitive. Our results demonstrate a novel nanomaterial biosensor approach for IAA quantification in plant tissue extracts. The results of the stress study clearly indicated that root and shoot elongation and growth had significant positive correlation with IAA content in the raw plant tissue extracts. Water and salt stress both reduced root and shoot growth, which may be due to overaccumulation of IAA, resulting in inhibition of elongation. In comparison to established methods, such as high-performance liquid chromatography (HPLC) or ELISA, our approach is simple and inexpensive. Unlike HPLC, our approach does not require any elaborate sample purification, nor does it require antibody development as needed for ELISA. In summary, this electroanalytical biosensor method can be effectively utilized for simple, cheap, and reliable detection of IAA extracted from plant samples.     

纳米材料对纽荷尔脐橙保鲜效果的试验研究

研究不同的纳米材料(纳米保鲜网套、纳米单果包装袋、纳米保鲜果蜡、纳米保鲜液)在纽荷尔脐橙常温贮藏过程中的保鲜效果,分别对其外观指标、理化指标和抑菌机理进行分析.结果表明,纳米果蜡(NLT)和纳米保鲜液(NYT)较对照有一定的防治效果,前者好果率较对照高17.15个百分点,后者好果率达到90％,虽然两者对柑橘果实贮藏期颜色没有产生显著影响,但在贮藏中可使可滴定酸稳定在0.75％～0.90％之间,可溶性固形物含量在12.0％以上,固酸比值稳定在13∶1和18∶1之间,Vc保持在40～60 mg/kg之间,并显著抑制了失水率的上升,降低了果实的呼吸强度,较好地保存了果实品质.通过对纳米材料的抑菌效力测定,纳米铜、纳米银及纳米铜银混剂等处理对青霉菌均有一定的抑制作用,其中有效成分20 μg/mL的纳米铜、20 μg/mL的纳米铜和纳米银的混剂抑菌效果最好,76 d抑制率高达99.8％,减缓了柑橘人工接种青霉菌的发生和发展,降低采后损失.但在纳米保鲜网套和纳米单果包装袋等复合材料中须进一步提高纳米离子的有效浓度,提高保鲜效果,并进行产品的开发利用.     

磁性纳米材料的合成及在细菌检测和去除中的应用

由于磁性纳米材料具有特殊的物理化学性质,它在环境污染治理中的应用已成为研究的热点,而其合成方法对磁性纳米材料的性能具有重要影响。在分析、总结近年来磁性纳米材料合成方法研究进展的基础上,比较了不同合成方法的特点;同时,对磁性纳米材料在细菌检测、捕获去除以及杀菌方面的研究进展进行了总结,并且在此基础上对磁性纳米材料在微生物污染控制领域的研究方向进行了展望。