Environmental Science

环境科学
  • 文章类型: Journal Article
    清洁供暖政策旨在减少空气污染,并可能为个人带来健康益处。基于以北京为中心的固定效应模型,这项研究发现,空气污染开始后,每日门诊就诊,住院天数,空气污染发生后几天,住院费用增加。在男性和女性以及三个不同年龄段中观察到了这些住院变化。建立了差异差异(DID)模型,以确定更清洁的供暖政策对健康后果的影响。研究表明,这项政策对健康结果有积极影响,所有疾病的诊所平均减少3.28万。总住院天数和费用趋于减少0.22万日和34万元人民币(人民币),分别。此外,实施该政策大大减少了呼吸系统疾病的日常诊所就诊次数,哮喘,中风,糖尿病,和慢性阻塞性肺疾病(COPDs)。
    Cleaner heating policies aim to reduce air pollution and may bring about health benefits to individuals. Based on a fixed-effect model focusing on Beijing, this study found that after the onset of air pollution, daily clinic visits, hospitalization days, and hospitalization expenses increased several days after the occurrence of air pollution. These hospitalization changes were observed in males and females and three different age groups. A difference-in-differences (DID) model was constructed to identify the influences of cleaner heating policies on health consequences. The study revealed that the policy positively affects health outcomes, with an average decrease of 3.28 thousand clinic visits for all diseases. The total hospitalization days and expenses tend to decrease by 0.22 thousand days and 0.34 million CNY (Chinese Yuan), respectively. Furthermore, implementing the policy significantly reduced the number of daily clinic visits for respiratory diseases, asthma, stroke, diabetes, and chronic obstructive pulmonary diseases (COPDs).
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  • 文章类型: Journal Article
    聚对苯二甲酸乙二醇酯(PET)微塑料和纳米塑料以大气和空气传播形式(PET-aMPs)普遍存在于大气中。使用第一原理计算,我们分析了主要空气污染物在PET-AMPs上的吸收,专注于他们的稳定性,吸附机制,和热化学。结果表明,PET-aMPs对CO的自发吸附具有选择性,CO2,NO,N2O,NO2,NH3和SO2,达到每分子6-20kcal/mol的稳定吸附能,具有与碳基材料相当的吸收能力,金属/准金属,和金属氧化物表面。然后,PET-aMPs成为大气中共存空气污染物的载体,根据气态分子的分子极性(偶极矩)和原子组成(电负性),通过内部或外部吸附进行吸附。此外,大气中的H2O和O2不是竞争性分子,由于表面氧化和结构破坏,臭氧可以增强吸附。静电(46-61%)和分散力(21-58%)的相互作用驱动了吸附机制,低极性污染物几乎显示出平衡的静电与色散贡献,而高极性分子显示出更高的静电稳定性。通过强分散达到外部吸附,氢键,和偶极-偶极感应对,而孤对电子相互作用出现在内部吸附状态中。这些结果扩大了对大气和空气中的微塑料/纳米塑料的危害和风险的理解,他们的影响,共同运输能力,与环境的互动。
    Polyethylene terephthalate (PET) microplastics and nanoplastics are ubiquitously present in the atmosphere as atmospheric and airborne forms (PET-aMPs). Using first-principles calculations, we analyze the uptake of primary air pollutants onto PET-aMPs, focusing on their stabilities, adsorption mechanisms, and thermochemistry. The results show that PET-aMPs are selective for the spontaneous adsorption of CO, CO2, NO, N2O, NO2, NH3, and SO2, reaching stable adsorption energies of 6-20 kcal/mol per molecule, with comparable uptake ability than carbon-based materials, metals/metalloids, and metal oxide surfaces. Then, PET-aMPs become a vector for coexisting air pollutants in the atmosphere, which adsorb by inner or outer adsorption depending on the molecular polarity (dipole moment) and atomic constitution (electronegativity) of gaseous molecules. Also, atmospheric H2O and O2 are not competitive molecules, and ozone could enhance adsorption due to surface oxidation and structure breakdown. The interplay of electrostatic (46-61%) and dispersion forces (21-58%) drives the adsorption mechanism, where low-polar pollutants display almost a balanced electrostatic vs. dispersion contribution, while high polar molecules display a higher electrostatic stabilization. The outer adsorption is reached by strong dispersion, hydrogen bonding, and dipole-dipole-induced pairs, while lone-pair-π interactions appear in the inner adsorption regime. These results expand the understanding of the hazards and risks of atmospheric and airborne microplastics/nanoplastics, their impacts, co-transport ability, and interaction with the environment.
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  • 文章类型: Journal Article
    在广义上,科学可以理解为科学期刊上发表的科学手稿中包含的知识。科学数据库仅索引达到某些质量标准的期刊。因此,科学知识的研究和传播是科学本身发展的重要活动。本手稿的目的是评估文献计量文献中医学和环境科学的状况,并将其与所有科学领域的总体文献计量出版物结合起来。出版文献计量手稿的主要国家是中国,美国和西班牙。根据Scopus和WoS数据库,后者在前五名机构中排名第三。在这两个数据库中,排名前20位的机构的平均科学合作提供了相同的结果,41%。根据Scopus的说法,这项研究属于的主要学科类别是社会科学(38%),计算机科学(26%)和医学(23%),而环境科学类别则占8%。仅在医学类别的分析中,据观察,有136个国家在这一领域做出了贡献。主要国家是美国,中国和英国。在医学领域,研究的主要领域是:流行病学,儿科,骨科,心脏病学,神经外科,放射学,眼科,肿瘤学,整形外科和精神病学。关于环境科学,国际传播较少,只有83个国家在这一领域工作过。主要是中国,西班牙和美国。关于十大机构,可以说,只有西班牙和中国是相关的。西班牙注重可持续性,中国注重环境。对所有已出版的文献计量手稿进行独立关键字分析的结果表明,主要聚类是:制图科学(29%),研究生产率(23%),医药(20%)环境科学(12%),心理学(7%)护理(6%)和工程(4%)。总之,医学和环境科学是继社会科学和计算机科学之后,文献计量学领域最相关的领域。
    In a broad sense, science can be understood as the knowledge contained in scientific manuscripts published in scientific journals. Scientific databases index only those journals that reach certain quality standards. Therefore, research and dissemination of scientific knowledge are essential activities for the growth of science itself. The aim of this manuscript is to assess the situation of medicine and environmental sciences among the bibliometric literature and to put it in perspective with the overall bibliometric publications in all scientific fields. The main countries publishing bibliometric manuscripts are China, USA and Spain. The latter country is ranked three out of the top five institutions according to the Scopus and WoS databases. In both databases, the average scientific collaboration of the top 20 institutions offers the same result, 41%. According to Scopus, the main subject categories in which this research falls are social sciences (38%), computer science (26%) and medicine (23%), while the environmental sciences category has 8%. In the analysis of the Medicine category alone, it has been observed that 136 countries have contributions in this field. The main countries are the United States, China and the United Kingdom. In the field of medicine, the main areas studied were: Epidemiology, Pediatrics, Orthopedics, Cardiology, Neurosurgery, Radiology, Ophthalmology, Oncology, Plastic Surgery and Psychiatry. With respect to environmental sciences, less international dissemination has been found, with only 83 countries having worked in this field. The main ones are China, Spain and the United States. Regarding the top 10 institutions, it can be stated that only Spain and China are relevant. Spain focuses on sustainability and China on the environment. The result of an independent keyword analysis of all published bibliometric manuscripts has shown that the main clusters are: Mapping Science (29%), Research Productivity (23%), Medicine (20%), Environmental Sciences (12%), Psychology (7%), Nursing (6%) and Engineering (4%). In short, medicine and environmental sciences are the most relevant areas in the field of bibliometrics after social sciences and computer sciences.
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  • 文章类型: Journal Article
    这项研究的目的是通过开发整体元模型(MM)来开发受海水入侵威胁的沿海Talar含水层的准确可靠的数值模型。与以前的方法相比,所开发的模型具有以下优势:(1)通过使用四种不同的元建模框架开发集成MM,即,人工神经网络,支持向量回归,径向基函数,遗传编程和进化多项式回归;(2)比较了基于16个集成的四个元建模框架的不同MM的精度;(3)含水层异质性对MM的影响。使用受海水入侵的说明性案例含水层评估了拟议的MM的性能。获得的结果表明,结合了所有四个元建模框架的集成MM优于GP和ANN模型,相关系数为0.98。此外,所提出的MM使用SVR-EPR的非线性学习集成实现了更好和鲁棒的预测性能。因此,它可以被认为是在变密度流中不同抽象模式下预测盐度水平的精确和鲁棒的模拟器。不确定性分析的结果表明,鲁棒性值和泵送率成反比,鲁棒性度量约为12%的场景更可靠。
    The aim of this study is to develop an accurate and reliable numerical model of the coastal Talar aquifer threatened by seawater intrusion by developing an ensemble meta-model (MM). In comparison with previous methodologies, the developed model has the following superiority: (1) Its performance is enhanced by developing ensemble MMs using four different meta-modelling frameworks, i.e., artificial neural network, support vector regression, radial basis function, genetic programing and evolutionary polynomial regression; (2) The accuracy of different MMs based on 16 integration of four meta-modeling frameworks is compared; and (3) the effect of aquifer heterogeneity on the MM. The performance of the proposed MM was assessed using an illustrative case aquifer subject to seawater intrusion. The obtained results indicate that the ensemble MM that combines all four meta-modeling frameworks outperformed the GP and ANN models, with a correlation coefficient of 0.98. Moreover, the proposed MM using nonlinear-learning ensemble of SVR-EPR achieves a better and robust forecasting performance. Therefore, it can be considered as an accurate and robust simulator to predict salinity levels under different abstraction patterns in variable density flow. The result of uncertainty analyses reveals that robustness value and pumping rate are inversely proportional and scenarios with a robustness measure of about 12% are more reliable.
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  • 文章类型: Journal Article
    在加纳,棕榈仁壳作为木炭生产中可再生能源的潜力尚未得到充分开发。使用由当地资源建造的低成本仪器(窑炉和压缩机箱),我们用棕榈仁(Elaeisguineensis)壳生产木炭压块。Further,我们在海岸角测量并比较了使用淀粉作为粘合剂与传统木炭和常用薪材(相思)的效率。遵循美国测试和材料标准(ASTM),对所有燃料进行了近似分析,结果表明生产的棕榈仁壳(PKS)团块的水分含量为1.08%,相比之下,木炭和薪材分别为9.25%和16.00%。挥发性物质,灰分含量和固定碳记录为71.80%,0.06%,PKS型煤中的27.07%,86.00%,0.78%,木炭占3.97%,80.50%,2.04%,薪材中分别为1.46%。烧焦的PKS的热值在结合形成其他燃料中具有最高价值的PKS团块后增加。其他燃料的热值为17.5MJ/kg的木炭,对于烧焦的PKS,18.72MJ/kg,PKS型煤为18.72MJ/kg。我们还进行了点火测试,燃烧试验,燃料燃烧率(FBR),以及PKS型煤和木炭的特定燃料消耗(SFC),以确定其作为烹饪燃料的适用性。与燃料质量分别为5.08g和25.5g的PKS团块相比,木炭易于点燃。所得团块具有理想的燃烧特性,例如无烟排放和灰分形成。与木炭相比,PKS煤块中的FBR和SFC最高。记录的值分别为2.84g/min和20.05g/ml,而木炭的值分别为0.42g/min和3.48g/ml。本研究生产的PKS型煤显示出高热值,低水分含量,和一个快速的燃烧速度在其他优异的性能。这些特性是潜在的指标,表明在加纳适当利用和生产PKS型煤作为可再生能源将有助于解决现有的能源危机。此外,减少气候变化的影响,通过减少家庭和商业供暖对薪材和木炭的过度依赖。
    In Ghana, the potential of palm kernel shells as renewable energy in charcoal production has not been exploited adequately. Using a low-cost instrument (kiln and compressor box) built from local resources, we produced charcoal briquette from palm kernel (Elaeis guineensis) shells. Further, we measured and compared its efficiency using starch as a binder to traditional charcoal and commonly used fuelwood (Acacia) in Cape Coast. Following the American Standards for Testing and Materials (ASTM), the proximate analysis was conducted for all fuels with results indicating that palm kernel shell (PKS) briquette produced had a moisture content of 1.08 %, as compared to 9.25 % in charcoal and 16.00 % in fuelwood. The volatile matter, ash content and fixed carbon recorded were 71.80 %, 0.06 %, and 27.07 % in PKS briquette, 86.00 %, 0.78 %, and 3.97 % in charcoal and 80.50 %, 2.04 %, 1.46 % in fuelwood respectively. The calorific values for charred PKS increased after binding to form the PKS briquette with the highest value among the other fuels. The calorific value for the other fuels were 17.5 MJ/kg for charcoal, 18.72 MJ/kg for charred PKS, and 18.72 MJ/kg for PKS briquette. We also conducted an ignition test, combustion test, fuel burning rate (FBR), and specific fuel consumption (SFC) on PKS briquette and charcoal to determine their suitability as cooking fuels. Charcoal readily ignited as compared to PKS briquette with respective fuel mass of 5.08 g and 25.5 g. The resultant briquette possesses desirable combustion characteristics such as no smoke emissions and ash formation. The FBR and SFC in PKS briquette recorded the highest in comparison with charcoal. The values recorded were 2.84 g/min and 20.05 g/ml respectively while that of charcoal was 0.42 g/min and 3.48 g/ml respectively. PKS briquette produced from this study showed high calorific value, low moisture content, and a fast burning rate amongst other excellent properties. These properties are potential indicators that the proper utilization and production of PKS briquette as renewable energy in Ghana would contribute to solving the existing energy crisis. Additionally, reduce climate change impacts, via the reduction in the over-dependence on fuelwood and charcoal for domestic and commercial heating.
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  • 文章类型: Journal Article
    建筑物改造在实现可持续发展方面起着至关重要的作用,是改善现有空间室内空气质量(IAQ)的有效途径。教室中的IAQ对学生的健康和学业成绩有重大影响。然而,如果允许最小的建筑修改,改善现有教室的IAQ是具有挑战性的。约旦科技大学提出了不同的自然通风改造技术,以改善现有教室的IAQ,它位于炎热的干旱地区。使用计算机模拟来分析通风率,室内工作温度,相对湿度,和CO2浓度在基本案例课堂和实施后提出的改造技术。将模拟结果与基本情况下获得的结果进行比较,以确定最有效的自然通风改造技术。最好的结果是使用太阳能烟囱辅助风塔,这导致了占用时间内的舒适时间增加,月平均通风率范围的改善,二氧化碳浓度的降低,和相对湿度比的改善。与使用分体式空调系统相比,可以实现39%的节能。使用净现值对拟议系统进行经济评估表明正的经济可行性。
    Building retrofitting plays a critical role in achieving sustainable development and is an efficient way to improve the indoor air quality (IAQ) of existing spaces. The IAQ in classrooms has a significant impact on the health and academic achievement of students. However, improving the IAQ of existing classrooms is challenging if minimum architectural modifications are allowed. Different natural ventilation retrofitting techniques were proposed to improve the IAQ in existing classrooms at Jordan University of Science and Technology, which is located in a hot arid region. Computer simulations were used to analyze the ventilation rate, indoor operative temperature, relative humidity, and CO2 concentration in the base Case classroom and after the implementation of the proposed retrofitting techniques. Simulation results were compared with those obtained in the base case to determine the most efficient natural ventilation retrofitting technique. The best results were obtained by using a solar chimney to assist a wind tower, which resulted in an increase in the comfort hours during the occupation time, an improvement in the average monthly ventilation rate range, a decrease in the CO2 concentration, and an improvement in the relative humidity ratio. An energy-saving of 39% would be achieved compared with the use of split unit air condition systems. Economic assessment of the proposed system using net present value indicates positive economic viability.
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  • 文章类型: Journal Article
    Due to the energy turnaround in German politics, it is necessary to integrate more and more wind and solar energy into the existing energy system. In particular, power generation is changing from a previously centralized to a decentralized structure, which also has consequences for requirements for safe, reliable and efficient grid operation. Generation and utilization characteristics will become more dynamic and flexible in the future. Increased demand for the measurement, control and automation of voltage and electricity will require the further development of grid infrastructure, the expansion of storage capacity and the introduction of information and communication technology (ICT)-based energy management (Appelrath et al., 2012). Utilities therefore need to know what migration paths into the future of a smart energy grid could look like. And this against the background of which technologies have to be installed, in which order this can happen and which dependencies have to be considered. The aim is to create roadmaps to the modern Smart Grid for two case studies. Within the framework of the Green Access project (Projekt Green Access, 2019), and (Flore & Kumm, 2020), a maturity model and, based on this, migration paths were developed for this purpose, which describe a path from one development stage to the next. It describes the necessary development steps that have to be implemented in the context of migration paths. These migration paths have been developed for a specially designed maturity model and describe the technologies used to move from one maturity level to the next. Finally, there will be a comparison of the developed migration paths of the two case studies.
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  • 文章类型: Journal Article
    综合方法,颗粒大小和形状,剂量优化,纳米肥料的毒性研究在其田间应用之前至关重要。这项研究调查了使用辣木和大块FeCl3在夏玉米(Zeamays)上的化学合成和生物合成的氧化铁纳米棒(NRs)的比较响应。发现FeCl3盐和化学合成的氧化铁NRs在高于25mg/L的浓度下会导致生长迟缓和植物生理和抗氧化活性受损,这是由于过度积累引起的毒性所致。虽然从生物合成的NRs中释放的铁由于其低毒性甚至在50mg/L时也显示出显著的阳性结果,叶面积改善(13%),单株叶片数(26%),获得具有生物合成NRs的总叶绿素含量(80%)和硝酸盐含量(6%)。此外,植物抗氧化活性在用生物合成的NRs处理时也增加,因为它们能够与金属离子形成络合物。这些发现表明,生物合成的氧化铁NRs是一种有效的铁源,可以持续很长时间。因此,证明纳米肥料需要具有特定的表面化学才能以适当的浓度释放养分,以改善植物生长。
    The synthesis methodology, particle size and shape, dose optimization, and toxicity studies of nano-fertilizers are vital prior to their field application. This study investigates the comparative response of chemically synthesized and biologically synthesized iron oxide nanorods (NRs) using moringa olefera along with bulk FeCl3 on summer maize (Zea mays). It is found that FeCl3 salt and chemically synthesized iron oxides NRs caused growth retardation and impaired plant physiological and anti-oxidative activities at a concentration higher than 25 mg/L due to toxicity by over accumulation. While iron released form biologically synthesized NRs have shown significantly positive results even at 50 mg/L due to their low toxicity, an improved leaf area (13%), number of leaves per plant (26%), total chlorophyll content (80%) and nitrate content (6%) with biologically synthesized NRs are obtained. Moreover, the plant anti-oxidative activity also increased on treatment with biologically synthesized NRs because of their ability to form a complex with metal ions. These findings suggest that biologically synthesized iron oxides NRs are an efficient iron source and can last for a long time. Thus, proving that nanofertilizer are required to have specific surface chemistry to release the nutrient in an appropriate concentration for better plant growth.
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  • 文章类型: Journal Article
    The Bangkok Metropolitan Area is an example of urban sprawl that has undergone rapid expansion and major changes in urban composition and building configuration. This city is now faced with the urban heat island phenomenon. Initial observations of land surface temperature (LST) in recent years have indicated that LST has tended to increase in both urban and suburban areas. The purposes of this study were to: (1) assess different land cover types and combinations of land cover composition along an LST gradient, and (2) investigate effect of building configuration types on the LST in densely urban areas. We analyzed the urban composition variation of 4,960 land cover samples using a 500 m × 500 m grid and configuration metrics in spatial patterns from Landsat 8 data and a high-resolution database of buildings obtained from GIS data of the Bangkok Metropolitan Area. The results indicated that the fraction of land cover composition was strongly related to LST. Our results suggested that LST can be effectively mitigated by using below green (shrubs, grasses, and yards), above green (trees, orchards, mangroves, and perennial plants) and water land cover. By increasing tree canopy to around 20%, water body to around 30% or green yard/shrub to around 40% of the built-up areas, it is possible to reduce LST significantly. Urban configurations (edge density, patch density, large patch, mean patch size, building height, compactness of building, building type, and building use) affecting on LST were studied. Increased edge density, patch density of buildings, and building height caused reductions in LST. Distribution of LST patterns can be significantly related with urban composition or land configuration features. The results of this study can increase understanding of the interaction between urban composition and configuration metrics. Moreover, our findings may be useful in the mitigation of the impact of LST in urban-sprawl cities.
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  • 文章类型: Journal Article
    An approach engaging Vertical Electrical Sounding (VES) and remote sensing data was carried out with a view to developing groundwater potential and aquifer vulnerability maps of the study area. One hundred and one (101) depth sounding data were acquired using Schlumberger array, with half maximum current electrode separation (AB/2) of 100 m. The VES were quantitatively interpreted using partial curve matching and computer aided iteration to determine the geoelectrical parameters of each station. The remote sensing data were processed using the application of Geographic Information System-based multi-criteria technique ArcGIS software. Eight (8) parameters namely lineament density, drainage density, slope, transmissivity, hydraulic conductivity, coefficient of anisotropy, aquifer thickness and resistivity were used to produce the groundwater potential model while five (5) parameters namely, lineament density, slope, longitudinal conductance, hydraulic conductivity and thickness of layer overlying the delineated aquifer were also used to produce the vulnerability model. The final output of overlay parameters for estimating the groundwater potential gave an index that ranged from 1-5. The zone categorised as low groundwater potential covered about 80% of the area. The majority of the area falls within low (about 80%) vulnerability and low groundwater potential rating while being relatively protected from potential contaminants infiltrating from the surface. The prediction accuracy of the groundwater potential model was established via existing hand-dug well correlation analysis.
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