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51.
Li QY Niu HB Yin J Wang MB Shao HB Deng DZ Chen XX Ren JP Li YC 《Colloids and surfaces. B, Biointerfaces》2008,65(2):220-225
To probe into the potential of relieving the oxidative damage of salt stress, we investigated the protective role of nitric oxide on barley under salt stress. Salt stress resulted in increased ion leakage, lipid peroxidation and protein oxidation in barley leaves. Simultaneous treatments of barley leaves with 50 microM sodium nitroprusside, a nitric oxide donor, alleviated the damage of salt stress, reflected by decreased ion leakage, and malendialdehyde (MDA), carbonyl, and hydrogen peroxide content in barley leaves. The presence of the nitric oxide donor increased the activities of superoxide dismutases (SOD), ascorbate peroxidases (APX), and catalases (CAT). Meantime, sodium nitroprusside addition increased accumulation of ferritin at the protein level, indicating that nitric oxide directly regulated ferritin accumulation. These results suggested that nitric oxide can effectively protect seedlings from salt stress damage by enhancing activities of antioxidant enzymes to quench the excessive reactive oxygen species caused by salt stress and inducing the increase of ferritin accumulation to chelate larger number of ferrous ion. Information from this study can be used to improve soil management practices for sustainable use of salt-affected soils in the future. 相似文献
52.
The mutual responses of higher plants to environment: physiological and microbiological aspects 总被引:3,自引:0,他引:3
Gang W Zhen-Kuan W Yong-Xiang W Li-Ye C Hong-Bo S 《Colloids and surfaces. B, Biointerfaces》2007,59(2):113-119
Higher plants are different from animals in many aspects, but the important difference may be that plants are more easily influenced by environment. Plants have a series of fine mechanisms for responding to environmental changes, which has been established during their long-period evolution and artificial domestication. The relationship between higher plants and environment is influenced mutually. The component in environment provides higher plants with nutrients for shaping themselves and higher plants simultaneously bring photosynthetic products and metabolites to surroundings, which is the most important part of natural circle. Photosynthetic products are realized mainly by physiological mechanisms, and microbiological aspects in environment (for instance, soil environment) impact the above processes greatly. The complete understanding of the relationship will extremely promote the sustainable utilization of plant resources and make the best use of its current potential under different scales. 相似文献
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55.
以石墨粉为原料,采用Hummers氧化法合成氧化石墨烯(GO).然后在超声作用下,将不同含量的Ag3PO4沉积在GO上,制备了一系列4% (w,质量分数) GO/Ag3PO4、8% GO/Ag3PO4、16% GO/Ag3PO4和32% GO/Ag3PO4复合光催化剂.对所制备的光催化剂运用N2物理吸附、X射线粉末衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、拉曼光谱、傅里叶变换红外(FT-IR)光谱、紫外-可见漫反射吸收光谱(UV-Vis DRS)等手段进行了表征,并在可见光下考察了GO含量对Ag3PO4光催化降解甲基橙(MO)的性能.结果表明, GO能够和Ag3PO4实现均匀复合.复合GO提高了催化剂的比表面积,改善了催化剂的吸附性能.复合16% GO使Ag3PO4光催化活性提高最显著, 120 min内对MO的降解率达到83%,是纯Ag3PO4光催化活性的7.5倍. GO能提高催化剂的比表面积,促进光生电子-空穴(e-/h+)的分离,产生更多活性自由基,从而提高Ag3PO4光催化的活性和稳定性. 相似文献
56.
Characterization of a velocity-tunable 87Rb cold atomic source with a high-speed imaging technology
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This paper has developed and characterized a method to produce a velocity-tunable 87 Rb cold atomic source for atomic interferometry application.Using a high speed fluorescence imaging technology,it reports that the dynamic process of the atomic source formation is observed and the source performances including the flux and the initial velocity are characterized.A tunable atomic source with the initial velocity of 1.4~2.6 m/s and the atomic source flux of 2 × 10 8 ~ 6 × 10 9 atoms/s has been obtained with the built experimental setup. 相似文献
57.
The interacting boson model-3(IBM-3) has been used to study the low-energy level structure and electromagnetic transitions of 68Ge nucleus. The main components of the wave function for some states are also analyzed respectively. The theoretical calculations are in agreement with experimental data, and the 68Ge is in transition from U(5) to SU(3). 相似文献
58.
The title compound ethyl 2-(6-(1,3-dioxo-4,5,6,7-tetrahydro-1H-isoindol-2(3H)-yl)-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4(3H)-yl) butanoate 3 was synthesized by the reaction of ethyl 2-(6-amino-7-fluoro-3-oxo-2H-benzo[b][1,4]oxazin-4(3H)-yl) butanoate with 4,5,6,7-tetraydrophthalic anhydride,and its structure was determined by X-ray single-crystal diffraction.The crystal belongs to the monoclinic system,space group P21/n with a = 9.3469(2),b = 16.7715(5),c = 13.7153(4) ,β = 104.9680(10)°,μ = 0.107 mm-1,Mr = 430.42,V = 2077.08(10) 3,Z = 4,Dc = 1.376 g/cm3,F(000) = 904,T = 296(2) K,R = 0.0508 and wR = 0.1478. 相似文献
59.
以正硅酸乙酯为前驱体,采用无溶剂水解技术,制备出了均一、稳定、透明的SiO_2溶胶,通过透射电子显微镜分析,粒径在100 nm左右;在溶胶中加入甲基丙烯酸甲酯(MMA)和偶氮二异丁腈(AIBN),采用热固化制备了透明的块体PMMA/SiO_2杂化材料,通过差热(DSC)和热重分析(TGA)研究了杂化材料的热性能. DSC结果表明,当体系中的SiO_2质量分数超过20%时,杂化材料无明显的玻璃化转变现象. TGA结果表明,杂化材料的分解温度提高约110 ℃. 透射电子显微镜观察结果表明,无机相均匀分散在有机相中,两相之间没有明显的相分离现象. 相似文献
60.
Hong-Bo S Xiao-Yan C Li-Ye C Xi-Ning Z Gang W Yong-Bing Y Chang-Xing Z Zan-Min H 《Colloids and surfaces. B, Biointerfaces》2006,53(1):113-119
Proline (content) is closely with plant anti-drought, especially under soil water deficits. Many reports from crops and other plants have proved this. Wheat is the second important crop on the globe, whose research in this aspect of importance for food quality, safety, and yield in field. The related difference in physiological indicators and proline content for different soil water treatments among wheat with different genotypes is not clear, which has limited deep study of wheat anti-drought molecular biology and related anti-drought biotechnological breeding. Our current study was focused on the physiological relationship of proline and different genotype wheat anti-drought under soil water deficits. Main results showed that different wheat genotype had different soil water stress threshold. Pro content had closed relationship with soil water stress threshold and wheat anti-drought. Developmental course also impacted Pro content for different wheat genotypes. 相似文献