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191.
192.
本研究基于垃圾车、分类投放点、回收服务点、垃圾中转站4类硬件投入要素,以上海市垃圾分类政策实施效果作为研究对象,利用数据包络DEA分析方法,针对2020年1月~2021年6月上海市强制性垃圾分类具体的实施效果逐月展开分析和评测.结果表明,条例颁布后,上海市生活垃圾分类总体实施成效较为良好,综合效率、纯技术效率和规模效率平均值分别为0.957、0.993、0.963,均处于相对有效状态,但部分月份存在投入冗余及产出不足情况,仍有很大的进步空间.建议将投入要素均衡地作用到可回收物、干垃圾、湿垃圾以及有害垃圾的城市生活垃圾处理方面,进而提升上海市可回收物、干垃圾、湿垃圾以及有害垃圾的处理水平,提高政策实施效率. 相似文献
193.
Yan Mi Prabowo Bayu He Lei Fang Zhumin Xu Zhang Hu Yanjun 《Journal of Material Cycles and Waste Management》2017,19(3):1279-1287
Journal of Material Cycles and Waste Management - A study for producing low moisture content sludge cake was performed by adding NaCl, CaCl2, Ca(OH)2, or FeCl3 to excess sewage sludge under... 相似文献
194.
Haiyan Chen Fei Wang Huilun Chen HongDa Fang Weiying Feng Yuan Wei FanFan Wang HaiLei Su YiDong Mi Min Zhou XinRu Li Serena Doni Andrea Corti 《环境科学学报(英文版)》2021,33(7):150-162
Eco-toxicity investigation of polymer materials was considered extremely necessary for their potential menace, which was widely use as mulching materials in agricultural. In this study, polyethylene (PE), polystyrene (PS) and synthetic biomaterials-Ecoflex and cellulose were applying into soil cultivated with two potential indicator plants species: oat (Avena sativa) and red radish (Raphanus sativum). Variety of chemical, biochemical parameters and enzyme activity in soil were proved as effective approach to evaluate polymers phytotoxicity in plant-soil mesocosm. The F-value of biomass, pH, heavy metal and electoral conductivity of Raphanus behaved significant different from T0. Significant analysis results indicated biodegradation was fast in PE than PS, besides, heavy metals were dramatically decrease in the end implied the plant absorption may help decrease heavy metal toxicity. The increase value at T2 of Dehydrogenase activity (0.84 higher than average value for Avena & 0.91 higher for Raphanus), Metabolic Index (3.12 higher than average value for Avena & 3.81 higher for Raphanus) means during soil enzyme activity was promoted by biodegradation for its heterotrophic organisms’ energy transportation was stimulated. Statistics analysis was carried on Biplot PC1 (24.2% of the total variance), PC2 (23.2% of the total variance), versus PC3 (22.8% of the total variance), which indicated phosphatase activity and metabolic index was significant correlated, and high correlation of ammonium and protease activity. Furthermore, the effects were more evident in Raphanus treatments than in Avena, suggesting the higher sensitivity of Raphanus to polymers treatment, which indicate biodegradation of polymers in Raphanus treatment has produced intermediate phytotoxic compounds. 相似文献
195.
以白腐真菌的中的黄孢原毛平革菌(Phanerochaete chrysosporium)为实验菌种,考察不同环境条件因素对P.chrysosporium降解磷酸三苯酯(TPhP)的影响以及TPhP降解过程中菌体细胞特性的变化.结果表明,当孢子液的接种量为4%(V/V),葡萄糖浓度为5g/L,pH值为5~6时,经过6d的处理P.chrysosporium对5mg/L TPhP的降解率可达到60%以上.菌体的细胞色素P450酶在TPhP的降解转化过程中发挥了重要的作用,抑制P450酶的活性会导致TPhP降解率下降.在降解反应的前期,为加快TPhP的代谢转化,菌体胞内蛋白含量以及ATP酶活性出现明显升高.在TPhP胁迫下,菌体SOD和CAT的活性随降解反应的进行呈现先升高后降低的趋势,2种抗氧化酶协同作用维持TPhP降解过程中菌体胞内的氧化还原平衡. 相似文献
196.
研究多点阵列冲击片雷管装药的热安全性。方法针对φ3 mm×3 mm、φ4 mm×4 mm、φ5 mm×5 mm、φ4mm×8mm共四种不同尺寸的HNS多点阵列装药开展慢速烤燃试验研究,得到HNS多点阵列装药在3.3℃/h、5、10℃/min三种不同升温速率下的响应特性。结果同规格装药情况下,随着升温速率的提高,其热烤响应剧烈程度有加剧趋势;同升温速率条件下,试样药量越大,反应剧烈程度有加剧趋势。结论阵列装药有利于分散HNS装药在热烤条件下的热积累,降低热烤试验的响应强度,提升装药的热安全性。 相似文献
197.
目的评估爆炸箔起爆器(EFI)在高空核电磁脉冲下的安全性。方法通过吉赫兹横电磁波室(GTEM)强电磁脉冲模拟系统,开展辐射方式下EFI电极塞在模拟高空核电磁脉冲(HEMP)下的感应电流试验测试。HEMP主要是通过电磁辐射方式在EFI脚线上耦合能量,在爆炸箔上产生感应电流,用光纤场强计监测模拟HEMP的电场强度,并在EFI爆炸箔电极塞脚线上套装电流环,通过示波器监测爆炸箔上的感应电流波形。结果在爆炸箔电极塞两根脚线上分别连接相同长度的导线,按导线长度不同分为5、10、20、30、40、50 cm共6组,使导线成180°状态,EFI的脚线可等效为偶极天线,感应电流随脚线长度增加而增大,两者呈线性关系。结论 EFI在HEMP下的感应电流远小于发火电流,对核电磁脉冲环境具有较高的耐受能力,具有较高的安全性。 相似文献
198.
The degradation of 2,2′,4,4′-tetrabromodiphenyl ether(BDE-47) by Pycnoporus sanguineus was investigated in order to explore the impact of the heavy metal Cu~(2+) on BDE-47 decomposition and the subsequent formation of metabolites, as well as to further elucidate the degradation mechanism of BDE-47. An increase in degradation rate from 18.63% to49.76% in the first four days and its stabilization at(51.26 ± 0.08)% in the following days of BDE-47 incubation were observed. The presence of Cu~(2+) at 1 and 2 mg/L was found to promote the degradation rate to 56.41% and 60.79%, respectively, whereas higher level of Cu~(2+) (≥ 5 mg/L) inhibited the removal of BDE-47. The similar concentration effects of Cu~(2+) was also found on contents of fungal protein and amounts of metabolites. Both intracellular and extracellular enzymes played certain roles in BDE-47 transportation with the best degradation rate at 27.90% and 27.67% on the fourth and third day, individually. During the degradation of BDE-47, four types of hydroxylated polybrominated diphenyl ethers(OH-PBDEs), i.e., 6′-OH-BDE-47, 5′-OH-BDE-47, 4′-OH-BDE-17, 2′-OH-BDE-28, and two bromophenols, i.e., 2,4-DBP and 4-BP were detected and considered as degradation products. These metabolites were further removed by P. sanguineus at rates of 22.42%,23.01%, 27.04%, 27.96%, 64.21%, and 40.62%, respectively. 相似文献
199.
Zhou Yingru Sun Kuangnan Mi Ying Luo Benxiang Xiang Jing Ma Taowu 《Environmental science and pollution research international》2022,29(11):15905-15914
Environmental Science and Pollution Research - Lead?zinc (Pb?Zn) processing and extraction activity generates large volumes of highly toxic and bare tailing (BT) wastelands which poses... 相似文献
200.
为探索原花青素对镉引起的鸡胚睾丸氧化损伤的缓解作用,本实验设置了对照组、镉、葡萄籽提取物原花青素(grape seed proanthocyanidin extract,GSPE)和镉+GSPE组,在胚胎期第6.5天(E6.5)注射0.05 mg·kg-1镉或2.5 mg·kg-1GSPE,统计孵化率和睾丸指数,并在E17.5检测睾丸形态、氧化指标、细胞凋亡和内质网应激相关基因的表达情况。结果表明:与对照组相比,镉处理组孵化率和睾丸指数均显著降低;睾丸组织结构出现了细胞核固缩、空泡化和染色质周缘化等变化,过氧化氢和丙二醛水平升高、超氧化物歧化酶活性显著降低、谷胱甘肽含量明显减少,凋亡细胞显著增多;睾丸中抗凋亡基因Bcl-2 mRNA表达水平下降,同时促凋亡基因Caspase3和内质网应激相关基因(XBP-1和HO-1)mRNA表达水平显著上升。然而,GSPE联合处理,明显缓解了镉引起的睾丸损伤,使孵化率和睾丸指数回升,抗氧化水平和内质网应激得到改善,凋亡细胞显著减少,睾丸形态趋于正常。结果表明:GSPE可通过其抗氧化作用降低XBP-1相关的内质网应激基因的表达,从而缓解镉引起的鸡胚睾丸生殖毒性。 相似文献