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981.
卷烟包装材料及滤嘴的生物降解性能研究   总被引:1,自引:0,他引:1  
本研究以目前几种常见的卷烟包装用商标纸、卡纸、铝箔内衬纸、透明塑料薄膜以及卷烟滤嘴为实验材料,采用ATSMD-5338标准方法,进行了为期25天实验。结果表明商标纸、铝箔纸内衬纸和卡纸的生物降解性能比较好,而滤嘴和透明塑料薄膜的生物降解性能比较差。今后研究开发可降解卷烟包装材料应该把重点放在滤嘴和透明塑料薄膜上面。  相似文献   
982.
983.
植物挥发性物质成分分析及抑菌作用研究   总被引:3,自引:0,他引:3  
张薇  程政红  刘云国  吴际友  贺迪 《生态环境》2007,16(5):1455-1459
对植物挥发性物质的化学成分及其抵抗微生物的能力以及与生态学相关可能产生的增效作用进行了研究。通过采用活体采气法收集20种园林植物的挥发性物质,利用气质联用仪测定物质成分结果,再进一步做抑菌作用研究。根据测定结果,实验最终确定的抑菌化学成分有:间羟基苯甲酸(m-hydroxybenzoic acid),水杨酸甲酯(methyl salicylate),邻苯二酚(catechol),乙酸(acetic acid),乙醚(acetaldehyde),丙烯酸(acrylic acid),乙硫醚(diethyl sulphide),莰酮-〔2〕(camphanone-2),莰醇-〔2〕(borneol-2)。同时,采用纸片扩散法和MIC(最小抑菌浓度)法对药品进行抑菌实验。结果表明:莰酮-〔2〕(樟脑)的抑菌效果最显著也最全面,水杨酸甲酯的抑菌效果最不显著也最不全面。丙烯酸、邻苯二酚、莰酮—[2]的最佳抑制细菌是金黄色葡萄球菌和酵母菌,质量浓度为0.156×10-3 mg.L-1时即可有效抑制这些微生物的繁殖,可根据这一特点,在医疗、食品中加以运用。从环境生态学角度看,在某些以空气传播的流行性疾病的多发地,特别是在呼吸道疾病曼延的地区,多栽种一些抑菌作用较强的植物(如银杏、香樟、枫香、海桐等),对疾病的控制有很强的现实意义。  相似文献   
984.
Three specialized cell types constitute the heterogeneous population present in the coelomic cavity fluid of sea urchins. The list includes: phagocytes, which undergo a stress-induced petaloid-filopodial transition, white or red amoebocytes and vibratile cells. As a whole, they act as the immune defense system of the sea urchin and respond to environmental and experimental challenge triggering specific stress markers. Here we extended our studies on coelomocytes short-term cultures by describing the morphology and occurrence of each cell type and analyzing their response to UV-B radiation at the biochemical level and with respect to DNA damage. The effects of different doses, ranging from 500 to 2,000 J/m2, on cells, which were then cultured in vitro for 1–6 h were tested. As early as 1 h after irradiation we found an increase in the levels of the heat shock protein70 (hsp) stress marker. A peak at 1,000 J/m2 corresponding to a 3.4-fold hsp70 increase over the levels of control coelomocytes was observed. Concurrently, we found an increase in the number of apoptotic nuclei detected by Hoechst staining, which varied from 7.1 to 15.6% in cells that were exposed to 500 and 2,000 J/m2, respectively. On the basis of our findings we confirm sea urchin coelomocytes as a sensitive cell culture system for environmental studies and propose their use for the analysis on the effects of UV-B radiation. Physical and Chemical Impacts on Marine Organisms, a Bilateral Seminar Italy-Japan held in November 2004. This paper is dedicated to the memory of Aurelia Koros, Ph. D., University of Pittsburg, who committed her scientific life to the study of natural killer cell antigens expressed in small lung carcinoma cells and sea urchin coelomocytes.  相似文献   
985.
Within the context of the EU Water Framework Directive (EUWFD), there is a demand for a holistic quality improvement of aquatic systems. Therefore, it is obvious that biodiversity is one of the quality components and hence has to be considered in detail. The ranking of habitats, based on biodiversity indices, depends on the specific measurement selected. It is postulated that a ranking of habitats by means of a biodiversity index may be ambiguous. Concepts to resolve this dilemma are demonstrated, and a graphical formalism is introduced which up to now has only been used in quantum mechanics, statistical mechanics, and theoretical chemistry: The YOUNG-diagram technique.  相似文献   
986.
In the coastal karstic region of SW Sardinia, from Capo Pecora in the north to Nebida in the south, many interesting geological monuments, ecotopes and several places of social and cultural interest that deserve preservation and valorization can be found. This mostly rocky coastline is characterized by the presence of a Cambrian sequence prevalently composed of limestones and dolostones and only locally of phyllites. A correct use of the many environmental and cultural monuments is necessary both to preserve and to valorize them; therefore they have to be properly managed in order to preserve their original natural conditions. Here, we describe and classify these monuments with the aim to propose an integrated model of sustainable development of this exceptional coastal landscape. Our model is based on several thematic maps according to which we propose the establishment of a natural reserve with specific geological and geomorphologic sites and the creation of several touristic circuits that are the basis for a further valorization of this territory.  相似文献   
987.
麻疯树胚乳类F-盒蛋白基因的克隆和载体构建   总被引:1,自引:0,他引:1  
通过随机测序从本实验室构建的麻疯树胚乳cDNA文库中获得了一条与多种植物、动物F-盒家族(F-box)序列相似的EST序列,并进一步克隆得到含有完整编码框的cDNA全长和基因组序列(Jc-Fbl1).Jc-Fbl1cDNA全长1672bp,开放阅读框为1224bp,编码的蛋白质含有407个氨基酸残基.Jc-Fbl1推导的氨基酸序列与拟南芥、水稻中的同源F-box蛋白相似性分别为52%和75%;与人、斑马鱼、线虫等动物的F-box蛋白的相似性达到48%~56%.应用Pfam Search寻找功能结构域,发现其除了含有F-盒家族类结构域外,还有富含亮氨酸重复单位(leucine-rich repeats,LRRs).比对Jc-Fbl1的基因组序列和cDNA序列,发现Jc-Fbl1有两个长度分别为331bp和893bp的外显子和一个长362bp的插入序列,符合内含子的GT-AG法则,认为是Jc-Fbl1的内含子.水稻、拟南芥基因组中的同源序列也出现了这种两个外显子、一个内含子的结构,且内含子位置较为保守.为了进一步研究麻疯树F-box蛋白的功能,构建了同时含有Jc-Fbl1完整开放阅读框序列和绿色荧光蛋白标签的真核表达载体pBI121-Jc-Fbl1-GFP,并经酶切鉴定构建成功.  相似文献   
988.
于2015年3月和7月,在南水北调江苏段沿线布设10个监测点,采集底栖动物30个分类单元,进行水生物学评价。结果表明,10个监测点底栖动物密度平均值为369个/m~2,优势种为霍甫水丝蚓、苏氏尾鳃蚓、克拉泊水丝蚓、梨形环棱螺、河蚬、铜锈环棱螺和方格短沟蜷,香农多样性指数均值为2. 14,BMWP指数均值为18,BI指数均值为7. 20。RDA分析结果显示,影响底栖动物的主要环境因子是DO、pH值和TN。指出,研究区总体水生态质量较好。  相似文献   
989.
Airborne particulate matter was collected and biomonitoring of workers was performed by sampling blood, urine and hair of 84 exposed subjects, 17 occasionally exposed employees, 21 controls from administrative offices and 25 unexposed people (external controls). Determination of Pd was performed using Quadrupole and High Resolution Inductively Coupled Plasma Mass Spectrometry. The Production of Catalysts Department and the Refining Service presented the highest levels of Pd in airborne matter collected by means of an area sampler. The highest level of soluble Pd (1.66 microg m(-3)) was found in the Production of Catalysts Department. The highest concentration of Pd in airborne matter, collected by means of personal devices (7.90 microg m(-3)) was found in the Refining Service. Hair showed a clear distribution pattern among departments, with values ranging from 0.60 to 5.54 microg g(-1). Administrative workers presented blood levels of Pd between 2 and 500 times higher than external controls. Only urine levels correlated with the measurements of airborne Pd collected with personal devices. A very strong association between airborne Pd collected by personal devices and Pd levels in hair (r(2)= 0.569, with p< or = 0.01) and urine (r(2)= 0.684, with p< or = 0.01) was found. On the basis of these findings: (i) blood results appear to be an unsuitable biological marker for occupational exposure to Pd; (ii) urine could be considered as a satisfactorily responsive bio-marker for occupational monitoring; and (iii) hair cannot be considered a good index of time-related exposure.  相似文献   
990.
Throughout Central America, the United States Agency for International Development (USAID), and the Zamorano Pan-American Agricultural School support a Safe Pesticide Use program. In 1993, a study of results was carried out among farmers and housewives in eastern Guatemala. Aspects of the methodology included: (1) participation of extension workers in all aspects of the study; (2) small, region-focused samples (eight cells, 30 interviews per cell); (3) comparison to control groups of untrained farmers and housewives; (4) a traditional questionnaire for studying acquisition of specific knowledge; and (5) a flexible instrument for building a cognitive map of knowledge and beliefs regarding pesticides. The cognitive map is a step toward applying modern psychocultural scaling, an approach already well developed for medicine and public health, to environmental problems. Positive results detected include progress at learning the meaning of colors on containers that denote toxicity and where to store pesticides. Pesticide application problems detected were mention by farmers of highly toxic, restricted pesticides as appropriate for most pest problems and of insecticides as the correct solution to fungus problems, and the widespread belief that correct pesticide dosage depends on number of pests seen rather than on land or foliage surface. Health-related problems detected were admission by a vast majority of housewives that they apply highly toxic pesticides to combat children's head-lice; low awareness that pesticides cause health problems more serious than nausea, dizziness, and headaches; and a common belief that lemonade and coffee are effective medicines for pesticide poisoning.  相似文献   
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