臭氧对无土栽培营养液的消毒作用研究

采用稀释平板法和MPN法,测定了臭氧对无土栽培营养液的消毒杀菌作用。结果表明,随着臭氧浓度(时间)的增加,对微生物杀灭率明显上升;连续处理20min,可杀灭90%以上的细菌、真菌和藻类;臭氧间歇曝气消毒营养液,有效控制微生物的滋生,对莴苣根系无不良影响,增加产量36.8%。     

抗臭氧型微生物培养基研究*

通常采用臭氧对水体进行灭菌,在臭氧与矿泉水混合后,当其浓度分别为０．１８３、０．３１１及０．５８４ｍｇ／Ｌ时,起始阶段臭氧分解速度较小,１．５￣５．５ｈ内其分解速度加快,至９．５ｈ后,在水中的臭氧浓度已降至０．０４０￣０．０６０ｍｇ／Ｌ,但要彻底分解则需２４ｈ以上。从抗消毒剂型微生物培养基基础上发展起来的抗臭氧型微生物培养基,在普通倾注平板法、大样倾注平板法、液体大样法和最小近似数法中,当检测含有     

臭氧对细菌杀灭作用的初步研究

本文以枯草杆菌,大肠杆菌,八迭球菌,金黄色葡萄球菌为研究对象,研究了臭氧作用时间,臭氧浓度与它们致死的关系,用臭氧作用前后细胞形态的变化。实验结果表明,在恒定的臭氧浓度下,随着作用时间的增长,致死率明显升高,且能达到１００ ％ 的致死率;作用时间相同,臭氧浓度减少,致死率下降     

臭氧对真菌杀灭作用的初步研究

以根霉 ,黑曲霉 ,青霉 ,酵母菌等为研究对象 ,测定了放电时间与致死率的曲线关系 ,并观察了与空白对照后其菌落形态的变化。实验结果表明 ,随着放电时间的增长 ,致死率明显升高 ,且能够达到完全杀菌。     

不同杀菌方式对水质理化特性及微生物指标的影响

目的：分析比较三种常见杀菌方式对生活饮用水水质理化特性的影响,为选择杀菌方式提供科学依据。方法：取某包装饮用水公司生产线用水8L,分为4组水样,每种水样各2L。4组水样再经过不同杀菌方式,组1经过超高温瞬时杀菌（UHT）处理,组2经过臭氧杀菌处理,组3经过高温煮沸处理,组4则不经过任何杀菌方式处理。采用核磁共振波谱法测定4组水样的分子团大小;采用有机聚合物生成反应原理测定氢自由基浓度;采用电极法测定电导率;采用离子色谱法测定溴酸盐含量;采用抑菌环法试验测定抑菌作用。结果：对于分子团大小,各组水样从小到大依次为组4（86.42Hz）<组1（87.02Hz）<组2（119.48Hz）<组3（132.32Hz）。对于氢自由基浓度,各组水样从大到小依次为组4（0.177mmol/L）>组3（0.142mmol/L）>组1（0.126mmol/L）>组2（0.111mmol/L）。对于电导率,各组水样从大到小依次为组3（71.8μS/cm）>组2（53.1μS/cm）>组4（49.8μS/cm）>组1（49.2μS/cm）。各组溴酸盐含量均<0.005mg/L,铜绿假单胞菌均未发现（CFU/250mL）,对金黄色葡萄球菌ATCC6538和大肠埃希氏菌ATCC25922均无抑菌能力。结论：不同杀菌工艺对水质理化特性有一定影响,相较于臭氧杀菌方式,超高温瞬时杀菌后水样的分子团最小,高温煮沸后水样氢自由基含量最高。     

山葵杀菌作用的研究

报道了山葵提取物对细菌的致死作用 ,特别是山葵对病原菌有明显的杀灭作用。在山葵提取物浓度为 0.5 %～ 0.8%,作用时间为 90～ 1 2 0min的条件下 ,对几种病原菌的杀菌率为 80 %～ 97%。这对杀灭有害病原菌找到了一条新途径 ,对防止病原菌的传播搞好环境卫生、保证人类健康有积极意义。     

稳定溶解臭氧水对皮肤创面炎症的治疗效果

目的:探讨浓度为1.8-3.2 mg/L溶解臭氧水冲洗控制皮肤创口炎症引发的红肿痛的临床效果。方法:将40例接受激光皮肤除斑治疗的患者分为两组,其中实验组20例患者采用浓度为1.8-3.2 mg/L溶解臭氧水冲洗皮肤创面,而对照组20例患者采用冰袋冷敷的方式处理创面。观察并比较两组患者皮肤创面红肿的改善情况以及两种治疗方法的临床效果。结果:1疼痛症状改善情况:实验组显效20例,对照组显效0例,实验组患者显效率明显高于对照组,差异具有统计学意义(P0.01)。2临床体征改善情况:实验组显效20例,对照组显效0例,实验组患者显效率明显高于对照组,差异具有统计学意义(P0.01)。结论:浓度1.8-3.2mg/L溶解臭氧水对于炎症引发的皮肤创面红肿症状具有显著的疗效,不仅能够抑制炎症发展,而且有利于促进创面愈合,值得在临床广泛推广应用。     

微生物磁学研究现状述评

近年来,有关微生物磁学特性的研究成为一个热点,主要集中在磁场作用下微生物的生物活性和致基因突变性的研究,利用脉冲电磁场灭菌和趋磁性细菌在工业、医学等方面的应用,以及磁场在农业上提高微生物增肥效果和矿冶上细菌的浸矿效果。     

利用微生物及微生物农药杀灭钉螺的初步研究

从洞庭湖血吸虫疫区土壤中分离出两种微生物 :紫红链霉菌Streptomycesviolaceoruber和自养黄色杆菌Xan thobacterautotrophics,将两菌进行培养 ,用稀释 10 0 0倍的培养液杀螺 ,结果表明 :处理 72h后 ,对钉螺的杀螺率分别为90 %、85 % ;BT生物杀虫剂、科诺特杀螟 5 5 %杀苏可性湿粉剂、科诺蔬丹 1.5 %苏阿可湿性粉剂、科诺千胜BT杀虫剂、华戎号 1.5 %甲胺基阿维菌素苯甲酸乳液 ,均稀释 10 0 0倍进行杀螺实验 ,结果发现含阿维菌素的微生物农药杀螺效果较好 (95 %— 10 0 % ) ,华戎号在 4 8— 72h之间其杀螺率均为 10 0 % ,而含BT的微生物农药杀螺效果相对较差(70 %— 95 % )。将微生物农药喷洒土壤进行的杀螺实验。结果表明 ,华戎号的杀螺效果较好 ,处理 4 8h后 ,杀螺率为 10 0 % ,千分之一的五酚钠溶液为对照杀螺剂 ,其杀螺率为 10 0 %。清水对照液的杀螺率为 0 %。     

基于功能催化剂的多因子消毒器对微生物气溶胶消毒效果

摘要 目的：利用空气消毒器能有效控制病原微生物在空气中的传播,但催化剂添加及多因子协同消杀的必要性及效果尚不明晰。方法：利用多因子消毒器,以白色葡萄球菌为指示菌,在30 m³标准试验舱开展了臭氧、紫外线、臭氧催化、紫外光催化、HEPA过滤等单一消杀因子及多因子协同消杀气溶胶中微生物的研究。结果：分别添加臭氧催化剂、光催化剂较单一臭氧、紫外线消杀率提高12.9%和11.33%;在多因子消杀中,协同臭氧催化-紫外光催化-HEPA过滤的多因子消杀较单一因子消杀率分别提高10.58%、36.37%、53.67%。此外,随着相对湿度从40%增加至80%,臭氧消杀率提高3.67%,而紫外线消杀率下降6.76%;随着设备风速由1.1 m/s增加到1.9 m/s,臭氧、紫外线、HEPA过滤的消杀率分别提高2.95%、8.08%和46.09%;臭氧发生量由5 g/h提高至10 g/h时,消杀率提高12.87%。结论：催化剂添加及多因子协同能提升消毒器的消杀效率,环境相对湿度、消毒器风速等因素会显著影响消毒器消毒效果。     

臭氧与氯对水蚤卵的孵化效应研究

水蚤是多种人体寄生虫的中间宿主,自来水厂常用臭氧和氯灭杀水蚤.本文研究了臭氧和氯以及氯在不同pH值水体中抑制水蚤卵孵化的效应浓度.结果表明:①各臭氧处理组(1～6 mg/L)中水蚤卵的孵化率(89.52％～97.85％)明显高于对照组(76.19％),臭氧对水蚤卵无灭活作用;②氯处理组(1～5 rg/L)中水蚤卵的孵化率为66.67％ ～ 96.00％,其中80％样品高于实验组的孵化率(78％),氯对水蚤卵无灭活作用;③在偏酸或偏碱的水体环境(pH5～6,pH9),随氯浓度增加,对其孵化率有极显著的抑制作用;④臭氧与氯对水蚤成体的灭活率达90％以上.经分析认为,自来水厂水池中的水蚤来源于原水以及炭滤池、砂滤池水内死水蚤受精卵的孵化,是净水厂反复发生水蚤的主要原因.提出利用臭氧或氯有效控制水蚤发生的处理技术.本研究在净水处理工艺中控制水蚤孳生方面具有实际应用价值与指导意义.     

Relating Ozone Uptake in Forest Trees to Risk Assessment

This paper reviews the importance of ozone uptake through plant stomata in understanding plant response to ozone and discusses challenges in quantifying ozone uptake in forest trees. Uncertainties in spatial and temporal scaling of ozone uptake from the leaf to the landscape level, insufficient monitoring of ozone in forested areas, and tremendous variability in the composition and structure of forest ecosystems of the United States prevent the current use of ozone uptake in large-scale risk assessments and regulatory decisions.     

Novel Comparative Efficiency of Ozone and Gamma Sterilization on Fungal Deterioration of Archeological Painted Coffin,Saqqara Excavation,Egypt

An archeological wooden painted coffin was excavated in Tety tomb from Saqqara excavation. It belonged to the Ministry of Antiquities. This coffin was discovered in a bad state of conservation with many destroyed big and small pieces in Saqqara stores. Analyses and investigation study were performed on the ground layer of the coffin by X-ray diffraction (XRD), Energy dispersive X ray analysis (EDX) equipped with environmental scanning electron microscopy (ESEM) and Fourier transform infrared spectroscopy (FTIR). Results confirmed that the degradation factors affecting the wooden painted coffin are essentially attributed to direct effects of microbial phenomena, which have lead to many deterioration forms as: macro- and microcracks, hydrated salts, flaking, coloration, scaling and defoliation microbiological spots. Nine deteriorating fungal species were isolated from the painted and ground layers of the tested coffin. Fusarium moniliforme followed by Aspergillus flavus able to significantly solublize calcium salts as major components of the ground layer of archeological wooden coffin. Effect of ozone and Gamma sterilization on growth; lipid, tryptophan oxidation and protein, nucleic acid leakage in the most dominant toxigenic deteriorated fungal species were detected. No mycelial growth was observed at 4 ppm of ozone at all exposure times. As Gamma radiation dose increased over 250 Gy, the growth parameter gradually decreased to reach the lethal dose at 2000 Gy. The production of mycotoxins by the tested toxigenic fungi was completely disappeared under the exposure to 3 ppm and 90 min to ozone.     

臭氧水对荔枝采后若干生理生化指标的影响

用不同浓度臭氧水对荔枝果实进行采后处理,测定其花色素苷、类黄酮、可滴定酸和糖含量以及多酚氧化酶和过氧化物酶活性。结果显示,处理后荔枝果皮中花色素苷、类黄酮含量下降速度低于对照,PPO活性低于对照,POD活性高于对照,而果汁中可滴定酸及糖含量与对照相比无显著变化。表明一定浓度臭氧水对荔枝果实保色护色有一定效果,并有防褐变作用。     

臭氧对生态系统地下过程的影响

对流层中高浓度的臭氧是一种严重危害植物的大气污染物,臭氧浓度的升高会对作物、林木等产生一系列的损害。本文综述了大气臭氧浓度升高对生态系统地下过程的影响,包括植物根系、根系分泌物、菌根、土壤-根呼吸、土壤酶以及土壤微生物的影响研究进展;阐述了目前研究中存在的争论以及今后需要研究的领域和方向。     

A Historical Overview of the Ozone Exposure Problem

Ozone can be found in essentially all locations in the troposphere. Too much exposure of vegetation and humans to this potent oxidizing gas can prove toxic. Reports of human toxicity to ozone first appeared in the 1800's from accidental occupational exposures when ozone was first discovered. Ozone was recognized as damaging field vegetation with a report of altered leaf morphology in grapes in the 1950s. Ozone is the major oxidant component in photochemical smog, and is produced by reactions of volatile organic compounds and oxides of nitrogen with sunlight present. Soon after the inception of the U.S. Environmental Protection Agency (US EPA), the Agency set a general “oxidants” standard (which included ozone) in 1971. A primary standard was created to protect human health and a secondary standard to protect against agricultural losses, ecological damage, and other losses. Ozone concentrations have decreased steadily over the last two decades in some areas of the U.S., but have increased in other areas. Several aspects of ozone exposure need further characterization, including better determination of rural concentrations and the relationship of outdoor to indoor concentrations. Ozone is one of the six criteria air pollutants requiring a formal reexamination of the new findings of effects on health and vegetation on a periodic basis, a process that leads to the publication of an US EPA criteria document. As a result of further study concerning ozone effects, significant changes were made to pollution standards in 1979 and 1997. This toxicant has remained a major air pollutant of concern in the U.S. despite regulation and intense study over several decades.     

Characterization of Gaseous Ozone Decomposition in Soil

Laboratory scale batch experiments were performed to investigate the decomposition characteristics of gaseous ozone in porous media. The decomposition rates of gaseous ozone in several solid media were determined, and the relationship of moisture content with sorbed ozone molecules was evaluated. Ozone decomposition in control and glass beads packed columns followed second-order reaction kinetics, while ozone consumption in a sand-packed column demonstrated first-order kinetics with a rate constant of 0.0109 min^?1 and half-life of 1.0 h. The presence of typical metal oxides in the soil resulted in ozone consumption rates in the following order: hematite (Fe₂O₃) > silica-alumina (SiO₂Al₂O₃) > alumina (Al₂O₃) > silica (SiO₂). Ozone decomposition was highly dependent upon soil moisture content. Over 90% of the total ozone mass decomposed in the field soil with moisture content at less than 1 wt%, whereas as low as 5–15% of the total ozone mass degraded with moisture content at more than 2 wt%. In conclusion, ozone decomposition in soils was primarily controlled not only by soil organic matter but also by reactive metal oxides on the soil surface. These two factors were shown to be highly dependent upon soil moisture content.     

Complexities in Understanding Ecosystem Response to Ozone

Ecological risk assessment of O₃ impact requires consideration of many factors that, perhaps, are not of concern in human health risk assessment. The episodic nature of O₃ exposure, functional complexity of species assemblages, and the broad spatial and temporal scales characteristic of natural ecosystems make ecological risk assessment extremely difficult. The majority of exposure studies using plants have examined the sensitivity of individual species, growing under controlled conditions. Research has shown that individuals growing in plant mixtures may not respond the same way to O₃ as when growing alone. In addition, other naturally occurring stresses can modify plant response to O₃. Understanding the effect of O₃ on natural systems and protecting vegetation resources represent significant scientific and regulatory challenges. Here we review several factors that need to be considered when evaluating ecosystem response to O₃. Then we briefly present two examples of controlled seedling studies that were conducted to better understand mechanisms of tree response to O₃. In the first example controlled exposure studies revealed responses in tree roots that led to hypothesis testing in the field in ponderosa pine ecosystems. Field experiments have confirmed a similar response in root biomass and carbohydrates across a natural O₃ gradient in S. California, suggesting at least a partial role for O₃ in the response. The second example illustrates the difficulty of understanding mechanistic interactions to O₃ stress even in controlled chamber studies. The second example also illustrates the difficulty of using chamber studies to understand responses in the field. While our knowledge of vegetation response to O₃ is extensive and compelling, important questions remain about how to quantify these effects in the field, assess their magnitude, and establish a suitable standard that is protective of ecosystems.     

臭氧对原位条件下冬小麦叶片光合色素、脂质过氧化的影响

运用开顶式气室(OTC-1)研究了O3胁迫对原位条件下冬小麦叶片的光合色素、脂质过氧化和抗氧化系统的影响.结果表明:随着O3浓度的升高,各个生育期小麦叶片中叶绿素含量下降,叶绿素组成发生改变,且在灌浆期变化明显;叶片相对电导率(REC)增大,丙二醛(M DA)含量增加;过氧化氢酶(CAT)、过氧化物酶(POD)活性和类胡萝卜素(C ar)含量降低,超氧化物歧化酶(SOD)活性在O3浓度低于1×10-7(φO3)时逐渐升高,而后急剧降低.可见O3促进了小麦叶片老化,加剧了膜脂过氧化,破坏了抗氧化系统功能,影响了叶片的正常生理代谢.