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1.
攀有火种,暂收缴.带手机,要关掉。要害部,最重要,出入人,登记好。交接班,要做好,各项事.记录到、守纪律,不违章,图省事,责难逃。摩托车,自行车,定地点,要放好。付油区.要做到,提油车,检查好.车进库,戴火帽、虽俪烦,不能少。收发油,操作好,按程序,必做勃。有静电、着不着,导静电.最可靠.化绷浸_,撇丁鞋,进汕库.要换掉,静电线,要传导,」妾卸油,要夹牢。搞维修,为安全,用电器,要防爆。要动火.开“火票,’,需批准,最重要,有措施,有监护.各环节.不减少。灭火器,保完好,灭火液,不失效。消防队,训练好,俏防泵,保养好,几砂钟,发动着,有火警,诅速到.…  相似文献   

2.
通过在一维煤粉燃烧炉上进行无烟煤添加高岭土吸附剂的燃烧实验,研究了无烟煤及其燃烧产物中18种环境有害微量元素的含量和分布;计算了高岭土在不同燃烧工况条件下对每种环境有害微量元素的吸附率.结果表明,高岭土对环境有害微量元素Cd, Pb, Sb, Sn, Ba, Co, Be, Cr, Ni, Mo, Tl, V, U, Mn, Th具有不同的吸附作用,吸附率为11.6%~500%;吸附效率与元素种类、燃烧工况等因素有关,环境有害微量元素Cd, Pb, Zn, Sb, Ba, Co, Be, Cr, Ni, Mo, Tl, V, U, Mn, Th的吸附能力,分级燃烧比不分级燃烧吸附效果更好,总吸附率差为8.4%~481%.  相似文献   

3.
Trace elements in atmospheric particulate matter play a significant role in air quality, human health, and biogeochemical cycles. In this study, the trace elements(Ca, Al, K, Fe, Na,Mg, Zn, Pb, Mn, Ti, Cu, Cr, Sr, Ni) in PM2.5samples collected at the summit of Mt. Lushan were analyzed to quantify their abundance, source, transport, and health risks. During the whole sampling period, the major trace elements was Ca, Al, and K. While the trace metals with the lowest concentrations were Sr, Ni, Rb,...  相似文献   

4.
乾隆的风扇     
过去的房子采光不好,避暑一流,民宅也好,官署也罢,尤其皇帝寝宫,都是很节能的。第一,墙体厚,晒不透,冬天暖,夏天凉;第二,屋顶大,窗户小,既挡寒,又遮阴;第三,材料多用土木,不用水泥,比热很高,温度难变,不会太热,也不会太冷。因为以上缘故,古人过夏天是不用开空调的。  相似文献   

5.
The principal objective of this study was to compare bioaccumulative properties of two terrestrial moss species Hylocomium splendens and Pleurozium schreberi from the Kielce area (south-central Poland), using various statistical techniques. Forty-six moss samples from 23 sampling sites located within the city limits were analyzed for 33 trace elements. The results indicated that 17 elements (Ba, Ce, Co, Cu, Eu, Fe, Gd, Hg, La, Mo, Nd, Ni, Pb, Pr, Sm, V, Y) dominated in H. splendens, whereas only three elements (Mn, Sr, Zn) occurred in excessive amounts in P. schreberi. No differences in the distribution pattern of Dy, Er, Ho, Sn, Tb, Th and Yb were observed. The element concentration ratio (PI/Hy) varied from 0.50 to 1.19. For 14 elements (Ce, Co, Cu, Fe, Gd, Hg, La, Mo, Nd, Ni, Pb, Sm, Th, V), PI/Hy < 1; for 4 elements (Cd, Mn, Sr, Zn), PI/Hy > 1; for 7 elements (Ba, Dy, Er, Eu, Pr, Y, Yb), PI/Hy = equalled 1. Czekanowski’s method showed similarities in rare earth element concentrations for both moss species. The cluster analysis exhibited three significant clusters at D link /D max × 100 < 50 for both moss species. Strong positive Spearman correlations between both moss species were recorded for the following pairs:Ba-Ba, Co-Co, Er-Er, Eu-Eu, Gd Gd, Mn-Mn, Ni-Ni, Pb-Pb, Pr-Pr, Sm-Sm, Th-Th, Y-Y, and Yb-Yb. Nonparametric tests (Sign test, Wilcoxon tests) showed statistically significant differences only for Cd, Ce, Co, Cu, Hg, Mo, Ni, Pb and Sr. The scanning electron microscope study of H. splendens and P. schreberi revealed a different morphology of these species with no injuries.  相似文献   

6.
入秋之后,早晚凉爽,气候多变,正是各种疫病的高发期。预防各种传染性疾病是秋季保健的第一要务,要注意个人卫生,养成良好的卫生习惯,增强保健意识。其次,是要注意饮食卫生。经过夏天的消耗,人体的消化功能下降,胃肠道抗病能力减弱,易患腹泻和肠胃炎,稍有不慎,就会染疾病而损伤健康。秋天气候干燥,要多吃水果和蔬菜,橙子、柠檬、乌梅能清热退火,是极佳的选择。饮食以清淡为主,“早餐”一碗粥,晚餐一碗汤,大鱼大肉等容易生火的食物尽量少吃。再者,在养生方面,要注意保暖,不要贪凉,夏季时,不少人习惯于敞开门窗睡觉,入秋后昼夜温差大,夜晚风凉,…  相似文献   

7.
为切实加强对中央和省级环保专项资金项目的管理,科学提炼项目,促进建设进度,提高资金使用效率,扎实推进环境改善和污染减排,近年来,山东省根据环保部要求,结合自身实际,按照"注重项目统筹,规范申报程序,严格审核审批,强化跟踪管理,做好绩效评价,确保发挥效益"的总体思路,大胆探索,逐步完善,采取一系列措施,积极推动和加强了环保资金项目绩效管理工作.  相似文献   

8.
1949年全国解放后,蒋家王朝留下来的是一个支离破碎的烂摊子,民生凋蔽,百业待兴,国外是帝国主义的军事威胁和经济封锁,国内是兵匪燹乱,部分地区连年灾荒,农业欠收,可谓是雪上加霜,人民生活极度困难。在这种形势下,党和政府为了休养生息,恢复生产,发展经济,富国强兵,在全国范围内,依靠人民群众,开展生产自救,共度难关。  相似文献   

9.
在语文教学中建构阅读课堂,加强阅读情感体悟,萌生良好阅读语感,积累丰富阅读信息,探究高效研读成果,获得有益的认知体验,滋养内心世界,熏陶美好情操,形成个性文化。眼下,阅读是学生语文学习的一个大难题,急需语文教师建构语文阅读高效课堂,创设语文情境,优化阅读方法,在阅读中,训练学生思维和想象力,丰富情感,增长智慧,使他们爱阅读,会学习,提升能力。  相似文献   

10.
In recent years, Dechloranes have beenwidely detected in the environment around the world. However, understanding and knowledge of Dechloranes in remote regions, such as the Arctic, remain lacking. Therefore, the concentrations of 5 Dechloranes in surface seawater, sediment, soil, moss, and dung collected from Ny-Ålesund in the Arctic were measured with the concentrations 93 pg/L, 342, 325, 1.4, and 258 pg/g, respectively, which were much lower than those in Asian and European regions. The mean ratios of anti-Dechlorane Plus (DP) to total DP (fanti) in seawater, sediment, soil, moss, dung, and atmospheric samples were 0.36, 0.21, 0.18, 0.27, 0.66, and 0.43, respectively. Results suggested that the main source of DP in seawater, sediment, soil, andmosswas long-range atmospheric transport. However, the ratio identified in dung was different, for which the migration behavior of the organism is probably themain source of DP.  相似文献   

11.
A hydroponic experiment was carried out to study intraspecific differences in the effects of different concentrations of cadmium (Cd)(0-10 mg/L) and arsenate (As(V)) (0-8 mg/L) on the growth parameters and accumulation of Cd and As in six wheat varieties Jing-9428, Duokang-1, Jingdong-11, Jing-411, Jingdong-8 and Zhongmai-8. The endpoints of wheat seedlings, including seed germination,biomass, root length and shoot height, decreased with increasing the Cd and As concentrations. Significant differences in seed germination, biomass, root length, shoot height and the accumulation of Cd and As were observed between the treatments and among the varieties (p < 0.05). The lethal dosage 50% were about 20, 80, 60, 60, 80 and 20 mg As/L for Jing-9428, Duokang-1, Jingdong-11,Jing-411, Jingdong-8 and Zhongmai-8, respectively, and the corresponding values for Cd were about 30, 80, 20, 40, 60 and 10 mg Cd/L, respectively. Among the six varieties, Duokang-1 was found to be the most resistant to Cd and As toxicity, and Zhongmai-8 was the most sensitive to Cd and As co-contamination. The resistance of the six varieties was found dependant on the seedling uptake of Cd and As. Duokang-1 was the most suitable for cultivation in Cd and As co-contaminated soils.  相似文献   

12.
The effects of arbuscular mycorrhizal (AM) fungus (Glomus mosseae) and phosphorus (P) addition (100 mg/kg soil) on arsenic (As) uptake by maize plants (Zea mays L.) from an As-contaminated soil were examined in a glasshouse experiment.Non-mycorrhizal and zero-P addition controls were included.Plant biomass and concentrations and uptake of As,P,and other nutrients,AM colonization,root lengths,and hyphal length densities were determined.The results indicated that addition of P significantly inhibited root colonization and development of extraradical mycelium.Root length and dry weight both increased markedly with mycorrhizal colonization under the zero-P treatments,but shoot and root biomass of AM plants was depressed by P application.AM fungal inoculation decreased shoot As concentrations when no P was added,and shoot and root As concentrations of AM plants increased 2.6 and 1.4 times with P addition,respectively.Shoot and root uptake of P,Mn,Cu,and Zn increased,but shoot Fe uptake decreased by 44.6%,with inoculation, when P was added.P addition reduced shoot P,Fe,Mn,Cu,and Zn uptake of AM plants,but increased root Fe and Mn uptake of the nonmycorrhizal ones.AM colonization therefore appeared to enhance plant tolerance to As in low P soil,and have some potential for the phytostabilization of As-contaminated soil,however,P application may introduce additional environmental risk by increasing soil As mobility.  相似文献   

13.
To demonstrate the existence of light thresholds in plant growth and to examine the effects of elevated CO2 on the shade tolerance of a tree species, an experiment consisting of a completely randomized design for a total of 96 yellow birch (Betula alleghaniensis Britton) seedlings was conducted with 3 light levels (2.9%, 7.7%, 26.1% of full sunlight)×2 CO2 levels (350 and 700±10 ppm) with 4 replications in a phytotron. The study proved that thresholds exist and they vary in different plant organs. In ambient CO2, the thresholds were 13.3%, 18.7%, 15.0%, 15.2%, and 15.6% of full sunlight for stem, leaf, root, total plant biomass, and the averaged value, respectively. In 700 ppm CO2, the corresponding thresholds were 16.7%, 21.3%, 18.1%, 21.7% and 19.5% for stem, leaf, root, total plant biomass, and the averaged value, respectively. The lowest threshold in the stem is an indicator of the minimal light intensity for regular growth for seedlings of this species. Below this threshold, light-stressful growth occurs. The result of a paired t-test indicated that the thresholds in elevated CO2 were significantly higher than in ambient CO2. This suggests that yellow birch will lose its moderate shade tolerance, evolutionally becoming a shade-intolerant species, and that it may become more difficult to naturally regenerate in the future.  相似文献   

14.
应用电子显微探针元素分析技术,对背角无齿蚌(Anodonta woodiana)的贝壳(棱柱层和珍珠层)进行了19种元素(Ag、Al、Au、Ca、Co、Cu、Fe、Hf、Mg、Mn、Mo、Na、Re、Se、Sn、Sr、Tl、V、Zn)分布特征的初步研究.元素面分布分析和定量线分析结果均直观而明显地表明:贝壳中Ca含量最高,Hf、Re、Mn、Al、Co、Fe、Sr、Cu和Na的含量较低,而Au、Mg、Tl、Zn、Sn、Ag、V、Mo和Se的含量甚少.Mn在珍珠层的分布高于棱柱层,壳顶区域的珍珠层的含量(0.087±0.045)%显著高于棱柱层(0.030±0.025)%(P<0.05),腹缘区域的珍珠层的含量(0.072±0.055)%亦显著高于棱柱层(0.044±0.025)%(P<0.05),而其余元素在贝壳中均匀分布.  相似文献   

15.
为探究青岛近海不同天气下气溶胶中金属元素的浓度分布特征,于2012年4~5月,2012年8月~2013年3月在青岛近海采集了总悬浮颗粒物(TSP)样品,利用电感耦合等离子体质谱法(ICP-MS)和电感耦合等离子体原子发射光谱法(ICPAES)分析了主要微量金属元素.结果表明,Al、Ca、Fe、Na、K和Mg是TSP中主要的金属元素,质量浓度占所测元素总浓度的94.2%.TSP及金属元素浓度月变化明显,Fe、Al、K、Ca、Mg、Zn、Ba、Mn、Ti、Sr和Li均在11月和1月浓度最高,Be、Sc、Co、Ni和Cr在1月最高,Na在8、11和2月较高,12月最低,Pb在1月和2月最高,8月和12月最低.富集因子表明Be、Co、Al、Ca、Fe、K、Mg、Mn、Sr和Ti主要受自然源影响,Li、Cr、Ni、Zn、Ba和Na除受自然源外,还受部分人为源影响,Pb主要来自人为源.不同天气状况对TSP及其金属元素浓度影响较大,除Ti外,所测元素浓度均在烟雾天最高.与晴天相比,烟雾天除Ti外,其余元素均升高,增幅为1~4倍,雾天Li、Be、Cr、Ni、Al、Fe、Mg和Mn变化不大,Pb和Na升高较多,Co、Ca和Ti降低较多,霾天Cr、Co和Ti降低,其余元素浓度升高,增幅为1~3倍.大部分元素在晴天富集因子最小,雾天富集因子最大.Ni、Zn、Ba、K、Na、Pb和Sr富集因子为晴<霾<烟雾<雾,Fe和Mn为晴<烟雾<霾<雾,Al和Mg为晴<雾<霾<烟雾,其余金属不同天气下富集因子的变化规律各不相同.  相似文献   

16.
In recent years, Dechloranes have been widely detected in the environment around the world. However, understanding and knowledge of Dechloranes in remote regions, such as the Arctic, remain lacking. Therefore, the concentrations of 5 Dechloranes in surface seawater, sediment, soil, moss, and dung collected from Ny-Ålesund in the Arctic were measured with the concentrations 93 pg/L, 342, 325, 1.4, and 258 pg/g, respectively, which were much lower than those in Asian and European regions. The mean ratios of anti-Dechlorane Plus (DP) to total DP (?anti) in seawater, sediment, soil, moss, dung, and atmospheric samples were 0.36, 0.21, 0.18, 0.27, 0.66, and 0.43, respectively. Results suggested that the main source of DP in seawater, sediment, soil, and moss was long-range atmospheric transport. However, the ratio identified in dung was different, for which the migration behavior of the organism is probably the main source of DP.  相似文献   

17.
Earthworm toxicity tests are useful tools for terrestrial risk assessment but require a hierarchy of test designs that differ in effect levels (behavior, sublethal, lethal). In this study, the toxicity of chlorpyrifos contaminated soil on earthworms was assessed. In addition to the acute and chronic tests, an avoidance response test was applied. Earthworms were exposed to sublethal and lethal concentration of chlorpyrifos, and evaluated for acute toxicity, growth, fecundity and avoidance response after a certain exposure period. The test methods covered all important ecological relevant endpoints (acute, chronic, behavioral). Concentration of 78.91 mg/kg, chlorpyrifos caused significant toxic effects in all test methods, but at lower test concentrations, only significant chronic toxic effects could be observed. In the present study, chlorpyrifos had adverse effect on growth and fecundity in earthworm exposed to 5 mg/kg chlorpyrifos after eight weeks. The avoidance response test, however, showed significant repellent effects concentration of 40 mg/kg chlorpyrifos. For chlorpyrifos, concentration affecting avoidance response was far greater than growth and fecundity, it seemed likely that earthworms were not able to escape from pesticide-contaminated soil into the clean soil in field and hence were exposed continuously to elevated concentrations of pesticides.  相似文献   

18.
IntroductionAswangovernorate ,Egypt ,isfamousforbymonuments (Ancient,CopticandIslamic) .Thefoundationareofthefirstimportanceandcareshouldbetakentoseethattheyareconsolidatedandprotectedasforaspossiblefromtheinfiltrationofwater.Waterisamajorcauseofdamage ,no…  相似文献   

19.
通过大气环流向海洋大气边界层传输的人为源和陆源物质,明显改变了海洋气溶胶中痕量金属的组成.但基于开阔海域岛屿连续观测研究海洋气溶胶中痕量金属元素组成及其来源的研究较少.2010年3—5月在我国台湾北部东海海域彭佳屿岛采集了60个TSP(总悬浮颗粒物)样品,采用电感耦合等离子体质谱仪(ICP-MS)分析了19种痕量金属(Al、Fe、Ti、Y、Mn、Ba、Sr、Co、Cr、V、Ni、Tl、Zn、Sn、Pb、As、Cd、Sb、Se)的质量浓度.基于TSP中Al浓度、气团后向轨迹分析和美国国家宇航局CALIPSO卫星星载激光雷达扫描图像,将采集的TSP分为非沙尘TSP(不受沙尘影响的TSP)和沙尘TSP(受沙尘影响的TSP).沙尘TSP中所有痕量金属的浓度都高于非沙尘TSP,表明沙尘对彭佳屿岛TSP中痕量金属有贡献.结合富集因子、相关性分析和PMF模型研究结果表明,彭佳屿岛春季非沙尘TSP中Al、Fe、Ti和Y主要来源于地壳矿物,Mn、Ba、Sr、Co和Cr同时受地壳矿物和人为源的影响;沙尘TSP中Al、Fe、Ti、Y、Mn、Ba、Sr、Co和Cr主要来源于地壳矿物.V和Ni在彭佳屿岛春季非沙尘TSP中主要来源于燃料油燃烧,而在沙尘TSP中同时受燃料油燃烧和地壳矿物的影响.非沙尘TSP和沙尘TSP中,Tl、Zn、As、Sn、Pb、Cd、Sb和Se的来源相似.Tl主要源于交通和煤燃烧,Zn、Sn、Pb、Cd和Sb同时来源于交通、煤和燃料油燃烧,As主要来源于煤燃烧,Se则主要来源于煤和燃料油燃烧.研究显示,人为源释放到大气中的Tl、Zn、As、Sn、Pb、Cd、Sb和Se可以通过大气环流长距离传输至开阔海域.   相似文献   

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