Polymer types

  • 文章类型: Journal Article
    本文研究了阿斯塔纳城市污水处理厂中MP的存在和去除,哈萨克斯坦首都。在100-5000μm大小的MP浓度在整个处理阶段进行了分析,采用改进的处理工艺方案,并对其去除效率进行了评价。污水处理厂出水的MP浓度较低(4.06±3.06MP/L至5.44±3.51MP/L),但考虑到每日废水排放量(253,900,000升/天),它可以显著促进水系统的MP污染。在进水中观察到季节性变化,夏季丰度较高,而在废水中没有观察到明显的趋势。污水处理厂达到88.6-93.0%的去除效率,机械处理和颗粒过滤是最有效的,其次是生物处理和紫外线消毒。在观察到的形状中,碎片最丰富(53.9-59.9%),黑色MPs占主导地位(44.7-67.5%)。聚乙烯(PE)是分析的MP中最普遍的聚合物类型(31.6-35.7%)。
    This paper investigated the MP presence and removal in the urban WWTP in Astana, the capital city of Kazakhstan. MP concentrations in the 100-5000 μm size were analyzed across treatment stages with a modified treatment process scheme, and their removal efficiencies were evaluated. The WWTP effluent displayed a low MP concentration (4.06 ± 3.06 MP/L to 5.44 ± 3.51 MP/L), but considering the daily wastewater discharge (253,900,000 L/day), it can significantly contribute to the MP pollution of aquatic systems. Seasonal variation was observed in the influent, with higher abundance during summer, while no significant trend was observed in the effluent. The WWTP achieved an 88.6-93.0 % removal efficiency, with mechanical treatment and granular filtration being the most effective, followed by biological treatment and UV disinfection. Fragments were the most abundant among the observed shapes (53.9-59.9 %) and black MPs dominated (44.7-67.5 %). Polyethylene (PE) emerged as the most prevalent polymer type among the MPs analyzed (31.6-35.7 %).
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  • 文章类型: Journal Article
    由于膨体灌溉的来源相似,有机肥,和污泥应用,微塑料(MPs)和抗生素在农业土壤中不可避免地共存。然而,不同聚合物类型和老化状态的MPs对土壤中共存抗生素的生物可及性的影响尚不清楚。因此,我们使用有机化合物器件(o-DGT)的扩散梯度膜来评估磺胺嘧啶(SDZ)在水稻土和用0.5%(w/w)MPs改良的盐渍土中的分布。四种聚合物类型(聚乙烯:PE,聚丙烯:PP,聚酰胺:PA,和聚对苯二甲酸乙二醇酯:PET)和MPs的两种老化状态(老化的PE和老化的PP)用于本研究。结果表明,土壤性质显著影响SDZ在土壤和土壤溶液中的分配,在盐渍土壤中,SDZ的降解速率较低,但迁移率较高。MPs对SDZ在水稻土和盐渍土之间的分配具有不同的影响。值得注意的是,PP将水稻土中不稳定的固相溶相分配系数(Kdl)降低了17.7%,而PE,PP,在盐渍土壤中,aPE使Kdl值分别增加了2.00、1.62和2.81倍。此外,在盐渍土壤中,所有的MP都降低了土壤溶液中的SDZ浓度,而在o-DGT阶段SDZ显著增加。相反,MPs不影响水稻土中SDZ的o-DGT浓度。此外,MPs增加了两种土壤中SDZ的R值,特别是在盐渍土壤中。这表明国会议员可能会增加SDZ从土壤到植物的再供应,特别是在盐水条件下。此外,与盐渍土壤中的原始MPs相比,老年MPs对这些指标的影响更为明显。因此,土壤中的国会议员对生物群吸收SDZ构成潜在风险,特别是在脆弱的环境中。此外,老年议员的风险加剧。
    Due to the similar sources of swage irrigation, organic fertilizer, and sludge application, microplastics (MPs) and antibiotics coexist inevitably in the agriculture soils. However, the impacts of MPs with different polymer types and aging status on the bio-accessibility of co-existing antibiotics in soils remained unclear. Therefore, we using the diffusive gradients films for organic compounds devices (o-DGT) to evaluated the distribution of sulfadiazine (SDZ) in both paddy soil and saline soil amended with 0.5 % (w/w) MPs. Four polymer types (polyethylene: PE, polypropylene: PP, polyamide: PA, and polyethylene terephthalate: PET) and two aging statuses (aged PE and aged PP) of MPs were used in this study. Results showed that soil properties significantly influence the partition of SDZ in soil and soil solution, and SDZ gained a lower degradation rate but higher mobility in saline soil. MPs pose different impacts on partition of SDZ between paddy soil and saline soil. Notably, PP reduced the labile solid phase-solution phase partition coefficient (Kdl) by 17.7 % in paddy soil, while PE, PP, and aPE increased the Kdl value by 2.00, 1.62, and 2.81 times in saline soil. Besides, in saline soil, all the MPs reduced the SDZ concentration in the soil solution, while significantly increased the SDZ in o-DGT phase. Conversely, MPs did not impact the SDZ\'s o-DGT concentration in paddy soil. Additionally, MPs increased the R value of SDZ in two soils, especially in saline soil. It suggested that MPs could potentially enhance the resupply of SDZ from soil to plants, particularly under saline conditions. Furthermore, aged MPs had a more pronounced effect on these indicators compared to virgin MPs in saline soil. Therefore, MPs in soil poses a potential risk for biota\'s uptake of SDZ, particularly in fragile environment. Moreover, the risk intensifies with aged MPs.
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  • 文章类型: Journal Article
    聚合物驱是一种提高采油率(EOR)的方法,用于提高油藏的采油率,超过一次和二次采油率。虽然它是最成熟的EOR方法之一,这种方法仍在不断有新的发展和评价。这主要归因于所使用的各种聚合物,这种方法在应用方面的扩展,以及由于实验室测试和现场应用的增加,与该主题有关的知识增加。在这项研究中,我们对实验室研究和现场应用中影响聚合物驱的因素进行了审查,以便就设计聚合物驱研究或应用时应包括的参数制定指南。初步探讨了聚合物驱油的主要机理,以及可用于聚合物驱油的聚合物类型。然后,我们讨论设计聚合物驱油项目时应包括的最突出的参数,基于以前的实验室研究和实地项目,讨论这些参数如何影响聚合物本身和驱油过程。这项研究可以为研究人员和工程师提供未来聚合物驱油研究或现场应用的指南。
    Polymer flooding is an enhanced oil recovery (EOR) method used to increase oil recovery from oil reservoirs beyond primary and secondary recovery. Although it is one of the most well-established methods of EOR, there are still continuous new developments and evaluations for this method. This is mainly attributed to the diverse polymers used, expansion of this method in terms of application, and the increase in knowledge pertaining to the topic due to the increase in laboratory testing and field applications. In this research, we perform a review of the factors impacting polymer flooding in both laboratory studies and field-based applications in order to create guidelines with respect to the parameters that should be included when designing a polymer flooding study or application. The main mechanism of polymer flooding is initially discussed, along with the types of polymers that can be used in polymer flooding. We then discuss the most prominent parameters that should be included when designing a polymer flooding project and, based on previous laboratory studies and field projects, discuss how these parameters impact the polymer itself and the flooding process. This research can provide guidelines for researchers and engineers for future polymer flooding research or field applications.
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  • 文章类型: Journal Article
    农业土壤的微塑料污染是全球环境关注的问题,因为其对粮食安全和人类健康的潜在风险。尽管许多研究已经测试了微塑料对ErucasativaMill生长的直接影响。,在田间管理实践中,对于这些影响是否受施肥和杂草竞争的调节知之甚少。这里,我们进行了一项温室实验,将紫花苜蓿作为目标物种进行三因子设计,并采用两种施肥水平(低与。高),两个级别的杂草竞争处理(杂草竞争与无杂草竞争)和五个级别的微塑料处理(无微塑料,聚己二酸丁二醇酯-共对苯二甲酸酯[PBAT],聚丁二酸丁二醇酯[PBS],聚己内酯[PCL]或聚丙烯[PP])。与没有微塑料的土壤相比,PBS和PCL降低了紫花苜蓿的地上生物量和叶片数。PBS还导致紫花苜蓿的根分配增加和根增厚。此外,施肥显著减轻了PBS和PCL对紫花苜蓿地上生物量的负面影响,但杂草竞争显著促进了这些影响。尽管施肥减轻了PBS对地上生物量的负面影响,在杂草竞争下,这种缓解变得比紫花苜蓿单独生长时更弱。结果表明,特定聚合物类型对紫花苜蓿生长的影响可能受到施肥的调控,杂草管理,甚至他们的互动。因此,合理的农场管理措施可能有助于减轻微塑料污染对农田中苜蓿生长的负面影响。
    Microplastics pollution of agricultural soil is a global environmental concern because of its potential risk to food security and human health. Although many studies have tested the direct effects of microplastics on growth of Eruca sativa Mill., little is known about whether these effects are regulated by fertilization and weed competition in field management practices. Here, we performed a greenhouse experiment growing E. sativa as target species in a three-factorial design with two levels of fertilization (low versus. high), two levels of weed competition treatments (weed competition versus no weed competition) and five levels of microplastic treatments (no microplastics, Polybutylene adipate-co-terephthalate [PBAT], Polybutylene succinate [PBS], Polycaprolactone [PCL] or Polypropylene [PP]). Compared to the soil without microplastics, PBS and PCL reduced aboveground biomass and leaf number of the E. sativa. PBS also resulted in increased root allocation and thicker roots in E. sativa. In addition, fertilization significantly mitigated the negative effects of PBS and PCL on aboveground biomass of E. sativa, but weed competition significantly promoted these effects. Although fertilization alleviated the negative effect of PBS on aboveground biomass, such alleviation became weaker under weed competition than when E. sativa grew alone. The results indicate that the effects of specific polymer types on E. sativa growth could be regulated by fertilization, weed management, and even their interactions. Therefore, reasonable on-farm management practices may help in mitigating the negative effects of microplastics pollution on E. sativa growth in agricultural fields.
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  • 文章类型: Journal Article
    微塑料(MP)由于其无处不在和出色的稳定性而受到越来越多的关注。我们检查了丰度,色散,以及孟加拉国图拉格河沉积物和鱼类中的MP属性,将工业城市加济普尔与特大城市达卡分开。将收集的样品消化并使用ATR-FTIR光谱法鉴定化学结构。沉积物中MP的浓度范围为10至35颗粒kg-1,平均丰度为19.2±2.44颗粒kg-1,碎片类型的MP占所有颗粒的34%。大多数MP在3-5mm尺寸范围内发现。来自图拉格河的淡水鱼肠道中的MPs浓度范围为0.63±0.18至7.0±1.1微塑料个体-1。纤维被发现是最常见的摄入MP类型(43%),其次是碎片(41%),电影(12%),和泡沫(4%)。最常见的MP类型是透明(34%),其次是红色(28%)。白色(20%),绿色(9%)和黑色(8%)。结果表明,底栖(1.87±0.39项个体-1)和底栖(1.5±0.26项个体-1)鱼类的MPs比中上层鱼类(0.63±0.18项个体-1)更多。发现聚丙烯(PP)是沉积物样品中最主要的聚合物类型,鱼样本中的PS(39%)。在沉积物和鱼类样品中发现聚乙烯(PE)占30%,PP占25%,分别。其他通常检测到的聚合物类型包括聚酰胺(PA),聚苯乙烯(PS),醋酸纤维素(CA),和聚对苯二甲酸乙二醇酯(PET)。在图拉格河沿岸的不同采样点,发现MP污染的污染负荷指数(PLI)处于I类风险水平。PLI值反映了城市的人为影响。这项研究的结果可用于为孟加拉国广阔的淡水生态系统中的MP污染建立基线。
    Microplastics (MPs) are a growing concern due to its ubiquitous presence and exceptional stability. We examined the abundance, dispersion, and attributes of MPs in the sediment and fish species of the Turag River in Bangladesh, which separated the industrial city Gazipur from the Mega-city Dhaka. Collected samples were digested and the chemical structure was identified using ATR-FTIR spectroscopy. The concentration of MPs in the sediment ranged from 10 to 35 particles kg-1, with a mean abundance of 19.2 ± 2.44 particles kg-1and MPs of the fragment type account for 34 % of all. The majority of MPs were discovered in the 3-5 mm size range. MPs concentrations in freshwater fish gut from the Turag River ranged from 0.63 ± 0.18 to 7.0 ± 1.1 microplastics individual-1. Fiber was found to be the most commonly ingested MPs type (43 %), followed by fragments (41 %), film (12 %), and foam (4 %). The most common type of MPs was transparent (34 %) followed by red (28 %), white (20 %), green (9 %) and black (8 %). The results showed that demersal (1.87 ± 0.39 items individual-1) and benthopelagic (1.5 ± 0.26 items individual-1) fish species had more MPs than pelagic fish (0.63 ± 0.18 items individual-1) species. Polypropylene (PP) was found to be the most dominant polymer type in the sediment sample, and PS (39 %) in the fish sample. Polyethylene (PE) was discovered to be 30 % and PP 25 % in sediment and fish samples, respectively. Other commonly detected polymer types include polyamide (PA), polystyrene (PS), cellulose acetate (CA), and polyethylene terephthalate (PET). In different sampling sites along the Turag River, the pollution load index (PLI) of MPs contamination was found to be in the risk level category I. The PLI values reflected the city\'s anthropogenic influence. The findings of the study could be used to establish a baseline for MPs pollution in Bangladesh\'s vast freshwater ecosystem.
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  • 文章类型: Journal Article
    在水生和陆地环境中,没有人为污染物比微塑料更普遍;然而,关于它的起源有很大的知识差距,命运,或者海洋中的时间变化。在这项研究中,我们在长期记录(2003-2015年)中分析了来自深亚热带东北大西洋(2000米)的沉积物陷阱物质,以评估深海作为微塑料潜在汇的作用.在所有110个分析样品中均鉴定出微塑料颗粒,通量率为1.13-3146.81项d-1m-2。计算出的微塑料质量通量介于0.10和1977.96μgd-1m-2之间,占颗粒通量的8%。几年之间,不同聚合物的组成发生了显著变化,以聚乙烯为主,其数量与成岩输入相关。聚乙烯与成岩部分之间的相关性归因于东北非洲和周边地区的航空运输途径。在我们的研究中检测到的第二丰富的聚合物是聚氯乙烯,与成岩或生物颗粒通量分数无关。相反,我们观察到聚氯乙烯的季节性,在浮游生物盛开之前的冬季反复出现高通量,而在夏季则显着降低。确定的其他聚合物是聚丙烯,聚对苯二甲酸乙二醇酯,和较低数量的聚苯乙烯和聚甲基丙烯酸甲酯。所有样品和聚合物的平均微塑料粒径为88.44±113.46μm,其中聚乙烯和聚氯乙烯具有最高比例的小颗粒(<100μm)。我们的发现为下沉的微塑料的时间变化提供了初步的见解,这对于理解海洋中塑料的命运至关重要。
    No anthropogenic pollutant is more widespread in the aquatic and terrestrial environment than microplastic; however, there are large knowledge gaps regarding its origin, fate, or temporal variations in the oceans. In this study, we analyzed sediment trap material from the deep subtropical Northeast Atlantic (2000 m) in a long-term record (2003-2015) to assess the role of the deep ocean as a potential sink of microplastics. Microplastic particles were identified in all 110 analyzed samples with flux rates of 1.13-3146.81 items d-1 m-2. Calculated microplastic mass fluxes ranged between 0.10 and 1977.96 μg d-1 m-2, representing up to 8% of the particle flux. Between years, the composition of the different polymers changed significantly, dominated by polyethylene, whose amount was correlated with the lithogenic input. The correlation between polyethylene and the lithogenic fraction was attributed to an air transport pathway from northeast Africa and surrounding regions. The second most abundant polymer detected in our study was polyvinyl chloride, which is not correlated with lithogenic or biogenic particle flux fractions. Instead, we observed seasonality for polyvinyl chloride with recurring high fluxes in winter before the plankton bloom and significantly lower amounts in summer. Other polymers identified were polypropylene, polyethylene terephthalate, and lower numbers of polystyrene and polymethyl methacrylate. The average microplastic particle size for all samples and polymers was 88.44 ± 113.46 μm, with polyethylene and polyvinyl chloride having the highest proportion of small particles (<100 μm). Our findings provide first insights into temporal variations of sinking microplastics, which are crucial for understanding the fate of plastic in the oceans.
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  • 文章类型: Journal Article
    黄色和深色粉虫(黄粉虫和黄粉虫)以高速率生物降解商业聚乙烯(PE)材料。我们使用高纯度微塑料(MPs)研究了物理和化学性质对生物降解的影响。其中包括高密度聚乙烯(HDPE),低密度聚乙烯(LDPE),和线性低密度聚乙烯(LLDPE),所有这些都具有不同的重均分子量(Mw)和不同的结晶度。两种粉虫的生物降解程度相似,但强烈依赖于聚合物的类型。因为LDPE>LLDPE>HDPE(各自的Mw为222.5、110.5和182kDa)。当测试Mw为0.84、6.4和106.8kDa的LDPEMP和Mw为52、105和132.7kDa的HDPE时,具有较低Mw的PEMP表现出更大程度的解聚。优势分析结果表明,较少的支化结构和较高的结晶度对解聚和生物降解产生负面影响。Py-GC/MS分析证实在所有测试的PE材料通过粉虫肠后,大分子主链的断裂以及氧化官能团的形成。结果表明,分子量,PE型,分支,结晶度显著影响粉虫对PE的生物降解能力,可能还有其他生物系统。
    Yellow and dark mealworms (Tenebrio molitor and Tenebrio obscurus) biodegrade commercial polyethylene (PE) materials at a high rate. We examined the impact of physical and chemical properties on biodegradation using high purity microplastics (MPs). These included high-density polyethylene (HDPE), low-density polyethylene (LDPE), and linear low-density polyethylene (LLDPE), all with different weight average molecular weights (Mw) and different crystallinity degrees in T. molitor and T. obscurus larvae. The biodegradation extent in the two mealworms was similar but strongly depended on the polymer type in sequence, since LDPE > LLDPE> HDPE (with respective Mw of 222.5, 110.5 and 182 kDa). When LDPE MPs with Mw of 0.84, 6.4 and 106.8 kDa and HDPE with Mw of 52, 105 and 132.7 kDa were tested, the PE MPs with lower Mw showed a greater extent of depolymerization. The results of dominance analysis indicated that less branching structure and higher crystallinity degree negatively impacted depolymerization and biodegradation. Py-GC/MS analysis confirmed the breaking of the macromolecule backbone as well as the formation of oxidized functional groups after all the tested PE materials passed through the mealworm intestine. The results demonstrated that molecular weight, PE type, branching, and crystallinity degree significantly affect the biodegradation capability of PE by the mealworms, and possibly by other biological systems as well.
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  • 文章类型: Journal Article
    Microplastics pollution in freshwater has attracted global attentions, but when microplastics are broken into nanoplastics, they may present higher toxicity mainly due to their greater potential to cross biological membranes. So far almost no work has been done on the separation and identification of nanoplastics in tap water. Herein we removed large particles from tap water by 0.45 μm filter and then sequentially screened nanoparticles in filtrate by Anopore with pore size of 200, 100, and 20 nm, the most frequent particle sizes of which concentrate at 255 nm, 148 nm, and 58 nm, respectively. Based on characterization of FTIR, AFM-IR and Pyr-GC/MS, the polymers were identified to be polyolefins, polystyrene, polyvinyl chloride, polyamide, and some plastic additives. The abundance of nanoplastics with the most frequent particle sizes in range of 58-255 nm was 1.67-2.08 μg/L in tap water. This work provides a feasible method for separation and identification of nanoplastics in tap water, and manifests the existence of nanoplastics, which poses a potential threat to the health of residents.
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  • 文章类型: Journal Article
    Plastic plays a major role in today\'s human life; moreover, it becomes a part of our life, yet it is a most challenging threat for the freshwater ecosystems in the future. The present study identifies, characterizes, and quantifies the microplastics in groundwater samples around Perungudi and Kodungaiyur municipal solid waste dumpsites in South India. To evaluate and assess the microplastic abundance, characteristics (composite, size, colour, shape, and surface morphology), detection methods of plastic particles, and potential risk factors from the absorption of microplastic in groundwater. Further, the microplastic particle classification was performed using LB-340 Zoom Stereo Microscope with LED Illumination, ATR-FTIR fitted with SEM with EDX analyzer. The groundwater samples (n = 20) were found contaminated with microplastic particles in the range of 2-80 items/L with coloured particles, white (38%), black (27%), green (8%), red (18%), blue (6%), and yellow (2%). The polymer type was found to occur in the following order: nylon (70%), pellets (18%), foam (6%), fragments (3%), fibers/PVC (2%), and polythene (1%). In both sampling sites, 90% of microplastics are derived from the buried plastics and waste fragmentation which are predominantly of polypropylene (PP), polystyrene (PS). Micro and nano plastics abundance in groundwater is of paramount importance as it has a major impact on human health. This study throws light on the characteristics and quantification of the microplastics in groundwater that initiates further research by which microplastics enter into the environment.
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