用GC-三级四极杆MS/MS一次进样筛选鱼和飞灰样品基质中四至八氯代PCDD/Fs的方法

用高分离能力的气相色谱-高分辨质谱(HRGC-HRMS)核实二噁英/呋喃是一项昂贵又费时的分析工作,需要高素质的仪器操作人员,而在认证分析前采用筛选法检查样品是检测不出还是浓度超出HRGC-HRMS方法定量范围,可以大大地减少HRGC-HRMS实验室的工作负荷.最新提供的信息表明约10%筛选过的样品需用HRGC-HRMS认证/核实.有些GC/MS/MS方法需要多次进样以获得有毒和无毒的PCDD/Fs,或用功能变换法[1-4]可以确保检测出所有的有毒的2,3,7,8-氯代PCDD/Fs,但损失某些无毒的PCDD/Fs(2,3,7,8氯代PCDD/Fs除外).     

Multi-drug resistance,integron and transposon-mediated gene transfer in heterotrophic bacteria from Penaeus vannamei and its culture environment

Environmental Science and Pollution Research - Multi-drug resistance (MDR) in bacteria is regarded as an emerging pollutant in different food production avenues including aquaculture. One hundred...     

SARS-CoV-2 phase I transmission and mutability linked to the interplay of climatic variables: a global observation on the pandemic spread

The study aims to determine the impact of global meteorological parameters on SARS-COV-2, including population density and initiation of lockdown in twelve different countries. The daily trend of these parameters and COVID-19 variables from February 15th to April 25th, 2020, were considered. Asian countries show an increasing trend between infection rate and population density. A direct relationship between the time-lapse of the first infected case and the period of suspension of movement controls the transmissivity of COVID-19 in Asian countries. The increase in temperature has led to an increase in COVID-19 spread, while the decrease in humidity is consistent with the trend in daily deaths during the peak of the pandemic in European countries. Countries with 65°F temperature and 5 mm rainfall have a negative impact on COVID-19 spread. Lower oxygen availability in the atmosphere, fine droplets of submicron size together with infectious aerosols, and low wind speed have contributed to the increase in total cases and mortality in Germany and France. The onset of the D614G mutation and subsequent changes to D614 before March, later G614 in mid-March, and S943P, A831V, D839/Y/N/E in April were observed in Asian and European countries. The results of the correlation and factor analysis show that the COVID-19 cases and the climatic factors are significantly correlated with each other. The optimum meteorological conditions for the prevalence of G614 were identified. It was observed that the complex interaction of global meteorological factors and changes in the mutational form of CoV-2 phase I influenced the daily mortality rate along with other comorbid factors. The results of this study could help the public and policymakers to create awareness of the COVID-19 pandemic.

     

Assessment of coal spontaneous combustion index gas under different oxygen concentration environment: an experimental study

Environmental Science and Pollution Research - Oxygen plays a crucial role in coal spontaneous combustion (CSC), and the magnitude of oxygen concentration determines the oxidation reaction...     

Do pilot free trade zones improve the green total factor productivity? Evidence from a quasi-natural experiment in China

China’s pilot free trade zone (PFTZ) is an important national strategy to achieve high-quality development, so it is necessary to discuss the effect of PFTZ implementation on green total factor productivity (GTFP). Based on the data from 279 cities in China from 2004 to 2018, this study takes the establishment of PFTZ as a quasi-natural experiment and uses the difference-in-differences (DID) method to systematically evaluate the effect of PFTZ on urban GTFP. The empirical results of this paper are shown as follows: Firstly, the construction of PFTZ has a significant effect on urban GTFP, and this effect has increased gradually over time. Secondly, the construction of PFTZ mainly promotes the urban GTFP by increasing the level of science and technology innovation, reducing government intervention and improving the level of human capital. Thirdly, the effect of PFTZ construction on GTFP is more pronounced in regions with earlier waves of PFTZ and in western regions where environmental concerns are higher. In addition, there is a significant positive linkage between the construction of the PFTZ and the Belt and Road Initiative to improve the urban GTFP. The findings of this paper enrich the relevant literature on PFTAs and sustainable development and provide a theoretical basis for further promotion of PFTZ construction.

     

Novel coronavirus (COVID-19) in environmental engineering perspective

Environmental Science and Pollution Research -     

Effects of tetracycline on the secondary metabolites and nutritional value of oilseed rape (Brassica napus L.)

Environmental Science and Pollution Research - Secondary metabolism, which helps a plant cope with external stress, is sensitive to environmental changes and plays a prominent role in maintaining...     

Weather integrated malaria prediction system using Bayesian structural time series model for northeast states of India

Environmental Science and Pollution Research - Malaria is an endemic disease in India and targeted to eliminate by the year 2030. The present study is aimed at understanding the epidemiological...     

Evaluation of physico-chemical and structural properties of biochar produced from pyrolysis of urban biowaste

Journal of Material Cycles and Waste Management - Understanding proper utilization and evaluation of biowaste materials in any metropolitan city across the world is crucial with respect to...