集装箱内食用动物产品外包装臭氧消毒方法的研究

利用箱外专用臭氧生发器向集装箱内输入臭氧,分别研究输入臭氧后停机密闭时间、输入集装箱内的臭氧量、集装箱内空气相对湿度、低温等单因素,对集装箱内装载的进境食用动物产品外包装的臭氧消毒效果的影响,并进行了外包装自然菌的现场杀灭试验。试验证实,向空气相对湿度70%的集装箱内持续注入臭氧时间60 min（输入臭氧量10 g）,停机密闭15 min,对装载食用动物产品外包装的防疫消毒是有效的。该方法具有可操作性,值得推广。     

紫外线(UV)-B增强对植物的影响研究

对大气中臭氧层变薄的现状及紫外线划分的方法进行了介绍。综述了国内外近几十年有关UV-B辐射对植物影响的研究现状,讨论了增强的UV-B辐射对植物生长及形态结构,植物生理生化代谢,UV-B吸收物质,植物遗传物质及某些基因表达,植物细胞膜及抗氧化系统,环境多因子相互作用对植物和种群及生态系统的影响,并对该研究领域今后的研究方向进行了展望。     

Quantifying the fine scale (1km × 1km) exposure and effects of ozone. Part 1. Methodology and application for effects on forests

Surface ozone concentrations show very large local variability. This, in rural areas, is largely a consequence of the degree to which the surface air is decoupled from the bulk of the atmosphere by nocturnal and winter stability effects and of the aerodynamic roughness and topography of the countryside. Procedures have been developed to simulate these effects and have been used with O₃ data from a regional monitoring network to quantify exposure of vegetation to mean and peak O₃ concentrations. The index of exposure to potentially phytotoxic O₃ concentrations is the AOT40 (accumulated exposure over a threshold of 40 ppb) expressed in ppb.h. The accumulated exposure of crop and forest surfaces to ozone is shown to increase approximately linearly with altitude and along a gradient from 3000 ppb.h in north west Scotland to 7000 ppb.h in the south of England. The area of UK forest which exceeds the critical level for ozone effects (10⁴ ppb.h above 40 ppb) totals 2.0 × 10⁴ km² and represents 47% of afforested land. The areas affected include most of southern and central England and Wales and large plantation forests of Northumberland and the Scottish borders.     

Soil processes and global change

 Contributors to the Intergovernmental Panel on Climate Change (IPCC) generally agree that increases in the atmospheric concentration of greenhouse trace gases (i.e., CO₂, CH₄, N₂O, O₃) since preindustrial times, about the year 1750, have led to changes in the earth's climate. During the past 250 years the atmospheric concentrations of CO₂, CH₄, and N₂O have increased by 30, 145, and 15%, respectively. A doubling of preindustrial CO₂ concentrations by the end of the twenty-first century is expected to raise global mean surface temperature by about 2  °C and increase the frequency of severe weather events. These increases are attributed mainly to fossil fuel use, land-use change, and agriculture. Soils and climate changes are related by bidirectional interactions. Soil processes directly affect climatic changes through the production and consumption of CO₂, CH₄, and N₂O and, indirectly, through the production and consumption of NH₃, NO_x, and CO. Although CO₂ is primarily produced through fossil fuel combustion, land-use changes, conversion of forest and grasslands to agriculture, have contributed significantly to atmospheric increase of CO₂. Changes in land use and management can also result in the net uptake, sequestration, of atmospheric CO₂. CH₄ and N₂O are produced (30% and 70%, respectively) in the soil, and soil processes will likely regulate future changes in the atmospheric concentration of these gases. The soil-atmosphere exchange of CO₂, CH₄, and N₂O are interrelated, and changes in one cycle can impart changes in the N cycle and resulting soil-atmosphere exchange of N₂O. Conversely, N addition increases C sequestration. On the other hand, soil processes are influenced by climatic change through imposed changes in soil temperature, soil water, and nutrient competition. Increasing concentrations of atmospheric CO₂ alters plant response to environmental parameters and frequently results in increased efficiency in use of N and water. In annual crops increased CO₂ generally leads to increased crop productivity. In natural systems, the long-term impact of increased CO₂ on ecosystem sustainability is not known. These changes may also result in altered CO₂, CH₄, and N₂O exchange with the soil. Because of large temporal and spatial variability in the soil-atmosphere exchange of trace gases, the measurement of the absolute amount and prediction of the changes of these fluxes, as they are impacted by global change on regional and global scales, is still difficult. In recent years, however, much progress has been made in decreasing the uncertainty of field scale flux measurements, and efforts are being directed to large scale field and modeling programs. This paper briefly relates soil process and issues akin to the soil-atmosphere exchange of CO₂, CH₄, and N₂O. The impact of climate change, particularly increasing atmospheric CO₂ concentrations, on soil processes is also briefly discussed. Received: 1 December 1997     

超声波臭氧组合果蔬清洗机设计与试验

通过融合超声波和臭氧两项清洗技术,设计了集去污、灭菌、降解农药残留等功能为一体的超声波臭氧组合果蔬清洗机.该机通过设计清洗自动控制程序,制定自动清洗工艺,设有喷淋漂洗、超声臭氧清洗和二次喷淋3个清洗过程,可完成果蔬全自动清洗.采用相向错位配置喷淋装置,结合程序控制,清洗过程中可使果蔬等发生间断性扰动和翻滚,实现换位清洗,提高清洗均匀性,增强臭氧混合效果.草莓清洗试验表明,本机对草莓品质无影响,灭菌率超过90％,对敌敌畏、乙酰甲胺磷和乐果等农药的降解率均为85％左右,灭菌、去污、降解农药残留效果显著.     

Solar UV-B dosimetry in situ with ‘D-dosimeter’: effect of ozone depletion on the Vitamin D synthetic capacity of sunlight

Vitamin D synthesis under solar UV-B radiation (280–315 nm) occurs widely in nature being an inherent characteristic of mammals and plants. Current data suggest that pro-Vitamin D can act as an UV-B receptor in plants, and thus monitoring the Vitamin D synthetic capacity of sunlight should be the subject of UV-B dosimetry. With this aim ‘D-dosimeter’ based on an in vitro model of Vitamin D synthesis has been designed for direct monitoring the Vitamin D synthetic capacity of sunlight in situ. Besides, ‘D-dosimeter’ possesses spectral selectivity that is helpful for detecting mid-latitude UV-B trends which accuracy is hindered by variations of solar UV radiation by clouds and aerosols, that have a comparable effect on UV-B caused by variations in stratospheric ozone.     

臭氧污染对水稻土物理结构和氮磷钾含量的影响

利用中国稻-麦轮作O3FACE(Free-air O3 concentration enrichment)试验平台,研究了连续3年大气O3浓度升高(比周围大气高50%)对稻田表层(0~20 cm)土壤团聚体、土壤容重及孔隙度和氮磷钾养分含量的影响。结果表明,大气O3浓度升高显著增加耕层土壤0.25~0.053 mm团聚体23.5%和降低<0.053 mm团聚体24.6%。O3污染具有增大0~10 cm土层和降低10~20 cm土层土壤容重的趋势,0~10 cm土壤中气体孔隙度显著减小39.8%,10~20 cm土壤中毛管孔隙度显著增加9.1%和气体孔隙度显著减小32.4%,改变了固、液、气三相比。长期O3污染显著降低土壤全氮含量10.5%和速效钾13.3%,显著增加有效磷40.8%,但对有效氮未产生显著影响。结果表明,长期臭氧污染将改变土壤物理结构和养分物质的生物地球化学循环。     

大气O3浓度升高对玉米光合作用和籽粒品质的影响

利用开顶式气室研究了大气O3浓度升高对玉米（Zea mays L．）叶片光合作用、籽粒品质以及产量的影响。结果表明,整个生长季内,与对照相比,在高浓度O3（80nmol／mol）条件下,玉米叶片的净光合速率、气孔导度、蒸腾速率显著下降（P〈0．05）,而胞间CO2浓度先降低后升高并达到极显著水平（P〈0．01）,这说明使光合速率降低的主要因素由气孔限制逐渐转变为非气孔限制。与对照相比,高浓度O3处理植株叶绿素a、叶绿素b及叶绿素（a＋b）含量降低,叶绿素a／b值则先降低后升高。但是随着熏蒸时间的延长,高浓度O3处理植株的叶绿素a、叶绿素（a＋b）含量与叶绿素a／b值变化呈先升高后降低的趋势,与叶绿素b含量变化不同;O3浓度升高在一定程度上使玉米籽粒品质下降,其中蛋白质和淀粉含量降低,而粗脂肪和蛋脂总量略有升高;百粒重、穗粒数和穗粒重均显著低于对照（P〈0．05）,说明O3浓度升高降低了玉米的光合能力,籽粒品质受到影响,抑制了作物生长。     

Effect of hydrogen sulfide on airway inflammation induced by ozone in mice

AIM: To investigate the effect of hydrogen sulfide (H₂S) on airway inflammation induced by ozone (O₃) exposure and its mechanisms.METHODS: C57BL/6 mice (n=32) were randomly divided into control group, O₃ group, NaHS+O₃ group and NaHS group. The mice in O₃ group and O₃+NaHS group were exposed to 2.14 mg/m³ O₃ for 3 h on days 1, 3 and 5, while the mice in control group and NaHS group were exposed to filtered air. NaHS (14 μmol/kg) was administered intraperitoneally to the mice in NaHS group and O₃+NaHS group 30 min before each exposure. After the last exposure for 24 h, the airway responsiveness was determined, and bronchoalveolar lavage fluid (BALF) was collected for counting inflammatory cells and measuring total protein concentration. The lung tissues were collected for observing the morphological changes with HE staining. The levels of interleukin-6 (IL-6), interleukin-8 (IL-8), malondialdehyde (MDA) and NF-κB p65 protein in the lungs were determined.RESULTS: Compared with control group, the airway responsiveness, inflammatory cells, protein concentration, inflammation score, levels of IL-6, IL-8, MDA and NF-κB p65 in O₃ group increased significantly, but these in NaHS+O₃ group decreased compared with O₃  group.CONCLUSION: The present findings suggest that H₂S attenuates O₃ induced airway inflammation by inhibiting NF-κB expression and preventing lipid peroxidation.     

YLO3-10W型智能臭氧发生器在黄瓜温室中应用初探

为研究臭氧的防治效果,以常规管理的温室为对照温室,以安装有臭氧发生器的温室为试验温室进行探索;并为了探究臭氧发生器在温室的应用效果,以中农26黄瓜品种为试验材料,来研究发生器对白粉病的抑制效果及臭氧的最佳使用浓度。结果表明:相比对照温室,黄瓜整个生长期结束后,使用臭氧发生器的温室杀菌剂使用量整体减少了77.8%。YLO3-10W型智能臭氧发生器能够显著抑制白粉病的发生。进一步研究发现,臭氧浓度达到0.20 mg/m~3以上时,能够显著抑制黄瓜白粉病的发生,而当臭氧浓度长时间维持在0.24 mg/m3以上时,会灼烧黄瓜叶片组织,影响黄瓜正常生长结实,即臭氧在黄瓜上的使用浓度为0.20~0.22 mg/m~3。综合来看,YLO3-10W型智能臭氧发生器的投入应用能够大幅减少化学药剂的投入,在一定程度上抑制黄瓜白粉病的发生。