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11.
生态等值分析法（简称HEA法）作为一种对自然资源损坏后做出准确损失效果评估,从而制定恢复实施方案的方法,其特点是原理清晰、参数较少、简单易用、实施便捷,所以在国外应用的领域比较广泛,也得到科学研究领域和社会法制界的认同,但目前在我国应用的较少。文章首先介绍了生态等值分析的概念和基本原理及组成部分,其次对该方法的相关因素进行了梳理和总结,然后以案例的方式分别从开始恢复时间、完成恢复时间和最大恢复服务水平三个角度的数据调整对该方法做了初步的探索应用,最后从实施、技术、经济三个方面对该方法在我国能否实际应用进行了讨论。结果表明,由于在技术条件、产权环境、经济背景等方面国内与国外存在一定的差异,所以HEA法在我国的确认和应用还需要一个探索的过程,并会随着生态补偿问题研究的深入而显得更加迫切。 相似文献
12.
腈纶废水的微波处理研究 总被引：1，自引：0，他引：1
应用微波技术对腈纶废水进行了降解处理,考察了反应时间、微波功率、溶液的酸碱性及催化剂对降解反应的影响,并考察了最佳反应条件下腈纶废水的可生化性能．实验结果表明,微波法处理腈纶废水的最佳条件为:反应时间为20s,功率为中档,初始pH=3-5;二氧化锰和二氧化钛两种催化剂对降解反应的催化效果比较明显,当每1L废水中加入1g此催化剂,pH=3-6时,化学需氧量(COD)去除率可达60％． 相似文献
13.
以钛酸四丁酯为钛源,硝酸银为银源,采用溶胶-凝胶法制备了掺银的纳米Ti02。用X射线衍射和透射电子显微镜对材料进行了表征,以掺银TiO2为催化剂对甲基橙进行了光催化降解实验。考查了催化剂掺银量、催化剂总用量、甲基橙溶液浓度及降解时间对甲基橙降解率的影响。结果表明,制得的样品颗粒细小均匀,3％掺银Ti02样品比表面积高达132．2m^2／g。掺银Ti02中的银钛原子摩尔比以及催化剂用量均影响光催化活性,银的掺杂量为3％时,纳米TiO2光催化活性最高,3％掺银TiO2催化剂最佳用量为0．3g/L。降解率随甲基橙初始浓度的增加而降低,随光照降解时间的增加而提高,光照20-30min之间．降解速度最快。 相似文献
14.
通过量化计算得出了烯酰吗啉分子的电荷密度分布和最优几何构型,分析了不同酸碱条件下光催化剂表面对烯酰吗啉分子的吸附和氢键的形成。用十二烷基磺酸钠对光催化剂表面改性有利于催化剂上烯酰吗啉的吸附,并对烯酰吗啉的光催化降解有显著的影响。在紫外光条件下,以Ag沉积量为0.125%的纳米Ag/TiO2为催化剂对浓度为100mg·L-1的烯酰吗啉稀水溶液进行光催化降解,5h降解率为94%。根据降解过程对烯酰吗啉浓度的高效液相色谱分析,液-质联用色谱分析和紫外-可见光谱分析,探讨了DMM的可能分解路径。 相似文献
15.
《Journal of Cultural Heritage》2014,15(3):227-233
Leaves of common deciduous trees: the horse chestnut (Aesculus hippocastanum) and linden (Tilia spp.) from the park, near one of the most important cultural institutions, the National Library of Serbia, were studied as bioaccumulators of heavy metal (Cr, Fe, Ni, Zn, Pb, Cu, V, As and Cd) air pollution. The leaf samples were collected from the urban park exposed to the exhaust of heavy traffic. The May–September heavy metal accumulation in the leaves, and their temporal trends, were assayed in a multi-year period (2002–2006). Comparing the obtained concentration of the investigated elements from the beginning to the end of growing seasons, a significant rate of accumulation was determined for a majority of measured elements, and it was concluded that these tree species (horse chestnut and linden) can be used as bioaccumulators of the investigated heavy metals. The SEM-EDAX analysis of individual particles deposited on the leaves showed that the 50–60% belong to a class of fine particles (D < 2 μm), mainly of anthropogenic origin. Thus, the investigated tree species could be grown as a natural barrier against urban air pollution in the vicinity of libraries, museums and other buildings for cultural heritage storage. 相似文献
16.
The objective of this study was to assess corrosivity of the atmospheric environment in the former Auschwitz I and Auschwitz II-Birkenau concentration and extermination camp, and to identify the protective properties of existing corrosion products in order to estimate the actual corrosion rate of original steel elements located there. The current atmospheric corrosivity of the former Auschwitz camp, specified during one year of exposure of steel samples according to the EN ISO 12944-2 (1998) standard, was determined and it can be described as a boundary between the low C2 and medium C3. The steel corrosion rate in these conditions was in the range of 14–34?µm/year with the average rate of 27?µm/year. A layer of corrosion products formed on uncovered original reinforcement steel rods during ca. 70 years of atmospheric exposure was examined in terms of their protective properties with respect to steel. The microstructure, chemical composition, and elemental chemical state were analyzed by means of scanning electron microscopy equipped with energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and X-ray diffraction. Potentiodynamic polarization and electrochemical impedance spectroscopy methods were employed to investigate the corrosion resistance of the carbon steel covered with a layer of corrosion products. It has been estimated that this layer slows down the corrosion rate of steel by about five times. Hence, it can be concluded that the corrosion rate of the original steel parts under the layer of corrosion products should not exceed 7?µm/year. 相似文献
17.
The impact of the spectral composition of light on the discoloration of paint pigments has been investigated for the case of lead chromate sulfate, an unstable yellow pigment used by Vincent van Gogh and other painters. With LEDification, museum lighting is moving from using halogen to LED lamps. LED light sources have a significantly different spectral composition than halogen lamps. To understand the impact of these differences on pigment stability, the wavelength dependence of pigment discoloration was determined. Contrary to the expectation that lower wavelength photons induce more damage than higher wavelength ones, UV (394?nm), blue, and cyan light all lead to similar levels of discoloration of a pigment for the same level of radiant power. By understanding this wavelength dependence, it becomes possible to create white light LED lamps with a spectral composition tuned to minimize the degradation effect. An existing LED solution with a modified emission indeed resulted in 30% less color change in the experiment than halogen. Furthermore, a method is proposed to optimize the LED spectra by tuning to the properties of each specific artifact. Simulations show that this can reduce the damage of the light source by 45% in specific cases. 相似文献
18.
Yvonne Shashoua 《文物保护研究》2016,61(3):208-213
Analysis suggests that progress in conservation of plastics objects and artworks can be described by a series of overlapping mesocycles. Focus has been placed for periods of 5–10 years each on determining the degradation pathways in the 1990s, developing strategies to inhibit those pathways from the late 1990s and, since 2006 on actively stabilizing and treating the symptoms of degradation. The primary driving forces behind the direction and rate of progress within each of these three mesocycles have been different and specific. The controlling factor in understanding degradation pathways for heritage plastics has been the origin of the data describing lifetimes. By contrast, mesocycles in developing suitable storage and display microclimates for plastics have mirrored preventive conservation practices for natural polymeric materials. The rate of the third mesocycle, interventive conservation, has been driven by the need to balance the requirements for reversibility in conservation practices with the artist's intent and significance. Developments within each of the three mesocycles from the 1990s to date are discussed in this article. Environmental science and toxicology of waste plastics offer a novel source of information about real time degradation in terrestrial and marine microenvironments that seems likely to contribute to the conservation of similar materials in contemporary artworks. 相似文献
19.
本文用碱性降解和表面活性剂作增敏剂 ,建立了一种新的测定土霉素的荧光法 ,土霉素和 0 .1mol/LNaOH反应产生具有更强荧光的物质 ,再加入CTMAB(十六烷基三甲基溴化铵 ) ,其荧光强度约增强 4.5倍 ,在 8.0× 1 0 - 9～ 1 .0× 1 0 - 6mol/L浓度范围内 ,其荧光强度与土霉素的浓度成正比 ,在尿液和血清中土霉素的测定有很满意的回收率 相似文献
20.
章介绍了具有合成H2O2和光催化性能的双功能新型复合电极，并用X－射线衍射，SEM等方法进行了表征，双功能复合电极是将TiO2/C光催化剂负载在具有合成H2O2性能的新型载体上形成的，在光反应器中，复合电极作阴，钌－钛不溶性电极作阳极，低压汞灯作光源，实现了光化学氧化与光催化氧化在同一电极／溶液界面上的联合作用，实验结果表明，复合电极对提高偶氮染料分子活性艳红（K－2BP）的氧化降解速度起到了重要作用，仅反应3min，脱色率可达49％，80min，偶氮染料分子可降解47％。 相似文献