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101.
102.
One methodology is proposed to estimate the quantification and composition of building-related construction and demolition (C&D) waste in a fast developing region like Shanghai, PR China. The varieties of structure types and building waste intensities due to the requirement of progressive building design and structure codes in different decades are considered in this regional C&D waste estimation study. It is concluded that approximately 13.71 million tons of C&D waste was generated in 2012 in Shanghai, of which more than 80% of this C&D waste was concrete, bricks and blocks. Analysis from this study can be applied to facilitate C&D waste governors and researchers the duty of formulating precise policies and specifications. As a matter of fact, at least a half of the enormous amount of C&D waste could be recycled if implementing proper recycling technologies and measures. The appropriate managements would be economically and environmentally beneficial to Shanghai where the per capita per year output of C&D waste has been as high as 842 kg in 2010.  相似文献   
103.
对峨眉拟单性木兰的果实、种子性状及种子内部结构进行了初步研究,并对其种子进行了离体培养.结果表明,峨眉拟单性木兰果实近卵圆形,红褐色;种子约扁,卵圆形似豆子,具假种皮,橘红色,含油脂;种皮黑褐色,坚硬光滑,具深浅不同的纹理;种子内含胚乳,种子萌发缓慢且萌发率低.  相似文献   
104.
在含油污水水质分析的基础上,采用烧杯实验和分光光度法研究絮凝剂的絮凝效果。筛选出以无机絮凝剂硫酸铝与两性高分子聚合物CE-3090的复配体系,同时研究了影响絮凝效果的因素并探究了其影响机理。结果表明:在温度为40℃,pH为7.72,170 r/min时高速搅拌1 min,然后50 r/min低速搅拌5 min,硫酸铝的加量为90 mg/L、CE-3090的加量为0.5 mg/L,絮凝沉降30 min后其絮凝效果较好。实验证明:该复配处理剂处理含油污水后,含油量和杂质含量都达到了SY/T 5329-94《碎屑岩油藏注水水质推荐指标及分析方法》油田污水回注的要求。  相似文献   
105.
我国体制转轨时期,面对当前的腐败,究其原因除了腐败本身具有的顽固性尚未得到根本遇制外,缺少科学的廉政考核体系也是一个重要原因.本文从我国公务员康政概念开始,通过一系列指标体系的测量,充分利用现代科技不断进行制度和方法的创新,不断完善我国公务员康政考核的指标体系.  相似文献   
106.
为了研究运动对2,3,7,8-四氯二苯并二恶英(2,3,7,8-TCDD)急性暴露大鼠肝组织酶活性的影响,将40只雄性Wistar大鼠随机分为正常对照组(NC)、染毒组(NT)、运动对照组(EC)、运动染毒组(ET)。染毒组(NT组与ET组)腹腔注射10μg·kg-1(以单位体重计)的TCDD,对照组(NC组与EC组)腹腔注射等量的玉米油;NT、NC组静养4周,ET、EC组运动(尾部负重5%游泳30分钟)4周。4周后,称重并宰杀大鼠,分离肝组织,称重后-80℃保存待测7-乙氧基异吩恶唑酮脱乙基酶(EROD)、7-乙氧基香豆素-O-脱乙基酶(ECOD)及芳香烃羟化酶(AHH)的活性。将数据进行多因素方差分析(MAVONA)处理,结果表明,染毒可降低大鼠体重,增加肝湿重和肝相对重量、增加EROD、ECOD活性;运动可增加大鼠肝相对重量、增加AHH的活性;染毒后运动可降低EROD、ECOD的活性。结论:急性10μg·kg-1(以单位体重计)TCDD染毒后4周可增加大鼠肝相对重量;4周的运动能有效降低TCDD对EROD、ECOD活性的激活作用。  相似文献   
107.
A pot experiment was conducted to study the allelopathic effects of initial decomposing leaf litter of Cinnamomum camphora on growth and physiology of Impatiens balsamina. Three leaf litter treatments included 20, 40 and 80 g of C. camphora leaf litter mixed with 8 kg of soil, namely T1, T2, and T3, respectively. In order to test the effect of leaf litter addition on the permeability and ventilation of soil simultaneously, a parallel trial with steamed leaf litter was conducted with the three treatments of the leaf litter. The leaf litter was steamed for 2 d to remove the secondary metabolites as much as possible, dried, and then mixed with 8 kg of soil, namely Z1, Z2, and Z3, respectively. No leaf litter was added in control (CK). The growth parameters of I. balsamina were determined at the 20 d, 60 d, 100 d and 120 d after sowing and the main physiology indicators were determined at the 60 d. The results indicated that: (1) The ground surface diameter and height of I. balsamina were inhibited significantly at 60 d (P < 0.05). Photosynthetic pigments and gas exchange parameters of I. balsamina were inhibited significantly at 60 d, and the inhibition effect was stronger with increased amount of leaf litter addition. The chlorophyll content, Pn and Ls decreased significantly with increased amount of leaf litter (P < 0.05). The activity of superoxide dismutase (SOD) and peroxidase (POD) in leaves of I. balsamina decreased with the increase of leaf litter addition. The content of MDA in treatments T1, T2 and T3 were all higher than that in CK, which indicated that I. balsamina suffered oxidative damage in a certain degree. The content of free proline (Pro) and soluble sugar (SS) in leaves of I. balsamina decreased significantly with the increase of the leaf litter (P < 0.05), while the content of soluble protein (SP) increased. (2) In the parallel trial, 60 d after sowing, no obvious difference was observed between CK and any steamed leaf litter treatment in terms of the morphological and physiological features stated above (P > 0.05). It indicated that the soil physical properties were not greatly influenced by leaf litter addition in the dose interval designed, or that the release of secondary metabolites from decomposing leaf litter was probably a better reason to explain the inhibition of leaf litter treatment to I. balsamina growth. (3)The compound effect (CE) of leaf litter decomposition on I. balsamina was enhanced with increase of the leaf litter, to 0.169, 0.354, and 0.497, respectively, in treatments of T1, T2 and T3. The study indicated that initial decomposition of C. camphora leaf litter in soil reduces the content of photosynthetic pigments, inhibits photosynthetic capacity and resistance physiology of I. balsamina, weakens its adaptability to the environment, and restrains growth of the plant. © 2015, Science Press. All rights reserved.  相似文献   
108.
 以鲤鱼为实验生物,应用流动式摄取及释放装置,进行了2,6-二硝基甲苯(2,6-DNT)的生物浓缩与释放研究。取得了2,6-DNT在鲤鱼(全鱼)、肝及肠部的生物浓缩曲线。全鱼的浓缩曲线可以稳态(平台式)曲线描述,但是肝、肠部浓缩曲线均呈峰形。肝部峰快速下降后渐趋稳态,肠部峰下降未得稳态。峰形,肝在先,肠在后。对比2,6-DNT在全鱼及肝、肠的生物浓缩曲线,并参照报道(1,2)指出,全鱼摄取曲线上各点所表现的浓度值为各时刻鱼体内各组织摄取化学品总重对全鱼重量的比值。肝、肠部峰形曲线预示了在肝、肠内生物浓缩过程发生了生物转化作用。对全鱼的生物浓缩过程应用单区一级动力学模型,求得BCF值与消除速率常数K1与K2,由K1/K2计算得到的BCF值与实测值相符。释放较慢,释放曲线呈双曲线形,半减期为4.8h。  相似文献   
109.
The spatial concentrations, seasonal trends, profiles and congener pairs of ambient polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) were investigated within a seasonally active sampling scheme during Jun 2008 and Jan 2009 in Tianjin City, northern China. The PCDD/F concentrations ranged 14.2-172 fg I-TEQ/m3 (average 69.3 fg I-TEQ/m3) in summer and (89.8-1.01) × 103 fg I-TEQ/m3 (average 509 fg I-TEQ/m3) in winter, respectively, except for the E-waste dismantling site where much higher values were observed (1.04 × 103 fg I-TEQ/m3 in summer and 7.123 × 103 fg I-TEQ/m3 in winter). The results indicated a significantly seasonal trend with higher TEQ values in winter as compared with summer, which could be related to increased emission sources and seasonal variations of the atmospheric boundary layer height. 2,3,4,7,8-PeCDF was the dominant contributor to the total PCDD/F toxic equivalents, and 2,3,7,8-TCDD was detected at almost all the sampling sites in winter. Most of the similarly substituted PCDD/F congener pairs exhibited high correlations, suggesting that they might have similar environmental fate or sources. But different seasonal and spatial distributions of PCDD/F concentrations indicated that the emission sources might be intermittent.  相似文献   
110.
• Effects of metabolic uncoupler TCS on the performances of GDMBR were evaluated. • Sludge EPS reduced and transformed into dissolved SMP when TCS was added. • Appropriate TCS increased the permeability and reduced cake layer fouling. • High dosage aggravated fouling due to compact cake layer with low bio-activity. The gravity-driven membrane bioreactor (MBR)system is promising for decentralized sewage treatment because of its low energy consumption and maintenance requirements. However, the growing sludge not only increases membrane fouling, but also augments operational complexities (sludge discharge). We added the metabolic uncoupler 3,3′,4′,5-tetrachlorosalicylanilide (TCS) to the system to deal with the mentioned issues. Based on the results, TCS addition effectively decreased sludge ATP and sludge yield (reduced by 50%). Extracellular polymeric substances (EPS; proteins and polysaccharides) decreased with the addition of TCS and were transformed into dissolved soluble microbial products (SMPs) in the bulk solution, leading to the break of sludge flocs into small fragments. Permeability was increased by more than two times, reaching 60–70 L/m2/h bar when 10–30 mg/L TCS were added, because of the reduced suspended sludge and the formation of a thin cake layer with low EPS levels. Resistance analyses confirmed that appropriate dosages of TCS primarily decreased the cake layer and hydraulically reversible resistances. Permeability decreased at high dosage (50 mg/L) due to the release of excess sludge fragments and SMP into the supernatant, with a thin but more compact fouling layer with low bioactivity developing on the membrane surface, causing higher cake layer and pore blocking resistances. Our study provides a fundamental understanding of how a metabolic uncoupler affects the sludge and bio-fouling layers at different dosages, with practical relevance for in situ sludge reduction and membrane fouling alleviation in MBR systems.  相似文献   
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