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371.
城乡能源消费格局是应对气候变化的重要议题,也是低碳治理的关键对象。市域尺度城乡能耗空间定量化研究对区域可持续发展及规划决策具有重要支撑作用。基于山东省潍坊市行业部门综合能源消耗量,结合兴趣点(point of interest,POI)大数据和土地利用等多源空间数据,统筹考虑企业数量、人口密度、车流量及耕地面积等关键因素,量化分析工业、生活、交通及农业部门的能耗格网空间分布。研究发现:工业、交通及生活用能的空间分布具有相似性;能源总消费量在各区域间具有差异性,呈现不同的热点分布特征,以团簇热点式分布为主;核心城区的能耗需求强烈,高强度用能区覆盖率显著高于其他地区。通过分析市域尺度上的能源消费格网格局特征,探索公里格网尺度下融合多源数据的空间可视化比较分析方法,可为区域低碳规划、国土空间规划以及可持续发展提供理论支持。 相似文献
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固体水造林效果试验研究 总被引:1,自引:0,他引:1
本文研究了达拉特旗固体水试验区固体水对土壤含水量、造林成活率、保存率和树木生长情况的影响及效果。结果表明,在鄂尔多斯干旱半干旱地区施用固体水,可以明显地改善土壤水分状况,施用固体水的三个树种的土壤含水量均比对照有不同程度的提高。尤其放置固体水的30-40cm土层,即植物根系的主要分布层的土壤含水量明显高于对照,与对照相比提高1.4%-3.6%;固体水处理对柠条、沙柳、杨树成活和保存均有明显的作用,与对照相比,分别提高了14.6%、19.6%、10.5%和14.2%、24.3%和13.5%;固体水对沙柳、杨树的植株生长也均有明显的促进作用,尤其生物量达到了对照的3倍左右。 相似文献
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实验采用Fenton反应-中和-厌氧菌法处理某高盐度工业废水,考察了各因素对COD去除率的影响。实验结果表明,Fenton反应处理该工业废水的最佳条件是:n(H2O2):n(COD)=2:1,n(H2O2):n(Fe2+)=4:1,pH=3,反应时间采用120 min。Fenton处理后废水COD由24 230 mg/L下降到13 020 mg/L,去除率达到46.26%;所得反应液用Ca(OH)2中和沉淀后COD值降低到11 060 mg/L,去除率为15.05%;最后废水经稀释后进行厌氧菌降解处理,COD为1 625 mg/L的废水经厌氧菌6天处理后降为466 mg/L,去除率为71.32%,达到GB8978-1996中规定的COD三级排放标准。 相似文献
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Shuangde Li Jiajia Gao Yiqing He Liuxu Cao Ang Li Shengpeng Mo Yunfa Chen Yaqun Cao 《环境科学学报(英文版)》2017,29(1):157-164
Particulate matter(PM) from cooking has caused seriously indoor air pollutant and aroused risk to human health.It is urged to get deep knowledge of their spatial-temporal distribution of source emission characteristics,especially ultrafine particles(UFP 100 nm) and accumulation mode particles(AMP 100-555 nm).Four commercial cooking oils are auto dipped water to simulate cooking fume under heating to 255℃ to investigate PM emission and decay features between 0.03 and 10 μm size dimension by electrical low pressure impactor(ELPI) without ventilation.Rapeseed and sunflower produced high PM_(2.5) around5.1 mg/m~3,in comparison with those of soybean and corn(5.87 and 4.55 mg/m~3,respectively)at peak emission time between 340 and 450 sec since heating oil,but with the same level of particle numbers 6-9 × 10~5/cm~3.Mean values of PM_(1.0)/PM_(2.5) and PM_(2.5)/PM_(10) at peak emission time are around 0.51-0.55 and 0.23-0.29.After 15 min naturally deposition,decay rates of PM_(1.0),PM_(2.5) and PM_(10) are 13.3%-29.8%,20.1%-33.9%and 41.2%-54.7%,which manifest that PM_(1.0) is quite hard to decay than larger particles,PM_(2.5) and PM_(1.0).The majority of the particle emission locates at 43 nm with the largest decay rate at 75%,and shifts to a larger size between137 and 555 nm after 15 min decay.The decay rates of the particles are sensitive to the oil type. 相似文献
379.
Development of a PCR strategy for thraustochytrid identification based on 18S rDNA sequence 总被引:4,自引:0,他引:4
The identification and characterization of the thraustochytrids, an emerging economically and biotechnologically important group of marine heterotrophic protists, is usually based on morphological characters. In this research we used molecular markers to identify thraustochytrids. We designed three sets of primers based on the 18S rDNA sequence alignment of known strains and employed a PCR (polymerase chain reaction) strategy to identify unknown thraustochytrid isolates. DNA from 26 thraustochytrids (three isolated from primary cell cultures of the tunicate Botryllus schlosseri and 23 from a coral holding aquarium) were amplified by these primers, revealing 21 isolates with three bands each, which were assigned to two groups according to PCR fragment sizes. Taxonomic characterizations were deduced by comparing with GenBank data. Four isolates were further studied by sequencing their 18S rDNA. Sequence alignments and phylogenetic analysis revealed that isolates from the coral aquarium (7-5 and 8-7) were highly similar to each other and 95.0-97.0% similar to Thraustochytrium multirudimentale and Schizochytrium minutum. Isolates from the tunicate primary cell cultures (BS1 and BS2) were also closely related to each other and 84.3-86.0% similar to labyrinthulid quahog parasite and Thraustochytrium pachydermum. AFLP (amplified fragment-length polymorphism) analysis revealed 2.5-3.6% differences within the genomic DNA of each group, showing that each isolate is different, although isolates within each group may belong to the same species, in spite of differences found in the general morphology. 相似文献
380.
Agnieszka Mościcka-Teske Marcin Butlewski Agnieszka Misztal Aleksandra Jacukowicz 《International journal of occupational safety and ergonomics》2013,19(4):510-518
This article shows the results of research on psychosocial risks for a group of machine and plant operators (n?=?1014) from the construction, chemical, energy, mining, metal and food industries in Poland. The Psychosocial Risk Scale designed in Nofer Institute of Occupational Medicine (NIOM) by Moscicka-Teske and Potocka was used to indicate the occurrence of general and specific occupational stressors and the level of their stressfulness. The results revealed that the studied machine and plant operators experience job context stress – related to working environment features concerning work organization – more frequently than job content stressors – related to the type of tasks they perform. Moreover, a correlation analysis between work features and the health and occupational functioning of the respondents revealed significant but weak relationships between the variables (from ?0.08 to ?0.23). Comparative analysis revealed the differences between the studied sectors. Such a comparison makes it possible to set goals for each sector and to attempt to improve the distinctive areas. 相似文献