Traditional corrosion inhibitors are not popular due to high toxicity. Instead, green corrosion inhibitors are appearing. Here, strictosamide as a green corrosion inhibitor was firstly separated from ...Uncaria laevigata, showing excellent solubility in hydrochloric acid solution. By means of electrochemical test, morphology measurement, and theoretical analysis, the corrosion inhibition ability of strictosamide on Q235 steel in corrosive medium was evaluated. Electrochemical results suggested that strictosamide revealed significant corrosion inhibition efficiency of 94.25% at 25 °C. Moreover, the inhibition effect was still strong with extension of immersion time, and the highest inhibition efficiency reached up to 94.90% for 48 h at 160 mgL−1. After the samples were immersed in the inhibited solution for 24 h, scanning electron microscopy and atomic force microscopy observations indicated that strictosamide was firmly attached to Q235 steel surface by making a protective film. Then, according to X-ray photoelectron spectroscopy results, Fe-N bonds existed on the steel showed the presence of chemisorption between metal ions and strictosamide molecules. Mainly because N atoms were complexed with Fe (II) to form stable complexes attached to the active position on steel. Hence, the stability and compactness of the adsorption film on metal surface were strengthened. Additionally, the inhibition mechanism of strictosamide was illustrated by molecular dynamics. Overall, strictosamide may exhibit the potential to replace the traditional toxic corrosion inhibitors in the industry.
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•Strictosamide was a novel green corrosion inhibitor for Q235 steel in acid medium.•After soaking in 160 mgL−1 for 48 h, the inhibition efficiency reached 94.90%.•Strictosamide showed good corrosion inhibition efficiency at high temperature.•The corrosion inhibition mechanism was discussed by molecular dynamics.
Adsorption is considered to be one of the most effective technologies widely used in global environmental protection areas. Modeling of experimental adsorption isotherm data is an essential way for ...predicting the mechanisms of adsorption, which will lead to an improvement in the area of adsorption science. In this paper, we employed three isotherm models, namely: Langmuir, Freundlich, and Dubinin-Radushkevich to correlate four sets of experimental adsorption isotherm data, which were obtained by batch tests in lab. The linearized and non-linearized isotherm models were compared and discussed. In order to determine the best fit isotherm model, the correlation coefficient (r2) and standard errors (S.E.) for each parameter were used to evaluate the data. The modeling results showed that non-linear Langmuir model could fit the data better than others, with relatively higher r2 values and smaller S.E. The linear Langmuir model had the highest value of r2, however, the maximum adsorption capacities estimated from linear Langmuir model were deviated from the experimental data.
Polymeric quaternary ammonium salts (polyquaternium-10 polymers, PQ-10) are extensively used as components of hair care products, lotions, and makeup and, therefore, are present in domestic sewage. ...Adsorption of these polymers by activated sludge was assessed to evaluate their removal by a commonly used wastewater treatment process. Activated sludge solids (ASS) were dosed with PQ-10 polymers with relatively high molecular mass (JR-125 and JR-30 M) and relatively low molecular mass (LR-400 and LR-30 M) and equilibrated for 2 h at 20 ± 2 °C. After equilibration, the vessels with the mixtures were centrifuged and the supernatants were analyzed with a phenol method.
The relationships between dosed amounts and equilibrium concentrations in the aqueous phase (dose-response curves) for each tested polymer indicated that at relatively low dosing solution concentrations were negligible (“total adsorption” region of the dose-response curve). Light absorbance of the samples prepared for determination of polymer concentration using a phenol method within this region was close to the absorbance of the blank (0 μg (a.i.)/mL) or below absorbance of the blank, resulting in calculated concentrations apparently below zero. At some level of dosing, a subsequent increase in polymer dosage resulted in a quantifiable increase in solution concentration (“solution concentration rising” region).
The relationships between concentrations of the polymers in the aqueous phase and concentrations of adsorbed polymers (adsorption isotherms) were non-linear. The ability of activated sludge solids to bind tested polymers may be characterized by apparent “threshold values” of the loading for each polymer. Below the “threshold value,” solution concentration of the polymer is close to zero and above this value it becomes measurable. “Threshold loading” for all polymers was from 50 to 100 mg (a.i.)/g, far above concentrations of these compounds expected to be present in the sewage.
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•Equilibration of PQ-10 polymers with ASS at dosing below 70–100 mg (a.i.)/g resulted in solution concentrations close to 0.•At higher dosing, increase in polymer dosage resulted in an increase of solution concentration.•The PQ-10 polymers adsorption isotherms were non-linear, “high-affinity type”.•“Threshold loadings” of PQ-10 providing solution concentrations close to 0 were higher than expected in sewage treatment.
Background: Proper biodiversity conservation and strategies for sustainability in environmental and public health are essential measures for addressing the problems of water-related and ...zoonotic-caused pandemics. It is generally assumed that a resurgence in an epidemic disease is directly linked to negligence in environmental protection policies, but there are sparse scientific publications supporting the claim. Methods: To address this issue, we collected data on the global pre- and post- industrialization scenarios and subjected it to multivariate analyses to investigate the relationship between the lack of proper environmental protection and the emergence of new diseases. Result: Our investigations found a statistically significant association between the loss of wildlife habitat and the emergence of novel diseases. The study also revealed that wildlife-related zoonotic disorders caused more than 220 million deaths amongst global pandemics. More than 30 million deaths were attributed to waterborne diseases due to improper waste management and wastewater treatment. Thus, it is recommended that other environmental parameters (e.g., pollution phase) need to be investigated to fully understand the complex relationship between environmental protection and emergence of new zoonotic diseases.
The safe, green, efficient and low-carbon coal mining is the common goal of surface coal mines around the world. The development intensity and ecological carrying capacity of surface coal mine ...resources in China show the reverse development characteristics, and the vulnerable ecological environment areas in northwest China have become the main surface coal production areas, which makes surface coal mining and ecological environment protection become important scientific problems, ecological problems and development problems to be solved urgently. On the basis of the development situation, natural conditions and main influencing factors of surface coal mines, the connotation characteristics and overall structure of realizing the safe-green-efficiency-low-carbon mining of surface coal mines were explained. Aiming at the characteristics of the whole life cycle of pre-mining, mid-mining and post-mining of surface coal mines, in terms of four levels: safe mining technology, green mining technology, efficient minin
Scientific research needs to get the most results with the lowest cost, hence how to modify the low-cost material to elevate its value is a valuable subject with both distinct scientific significance ...and extensive potential commercial application. This mini-review reports many achievements on this subject, in which amorphous silica is the starting material. Amorphous silica is a common porous oxide with a relatively low cost, but it can be modified to act as various new functional materials as long as the adopted strategy is smart and accurate. As these achievements are revealed in this review, silica can exert its versatility in environment protection as the efficient trapper of volatile nitrosamines, phenol and organophosphorus pesticide. Besides, silica plays the significant role of a solid strong base and thermal releaser of menthol, providing a clue on how to update the low-cost material into a specific new functional material.
This paper aims to highlight the development of international environmental protection standards with the emergence of environmental management systems aimed at managing the impact of the institution ...and ensuring its commitment to local and international environmental policies and laws. There are several criteria developed by governments and international bodies, as well as other indicators adopted by non-governmental organizations, all of which are considered non-binding but are considered modern mechanisms that contribute to improving environmental performance. So, environment protection has become one of the important factors that should be taken into consideration when making investment decisions.
China is considered to be one of the most drought prone countries. This study is dedicated to analyzing the regionalization and spatiotemporal variations of drought based on the Standardized ...Precipitation Evapotranspiration Index, which covers the period 1961–2013 across 810 stations in China. Using Spatial “K”luster Analysis by Tree Edge Removal method, China was divided into eight regions: southwest (SW), northeast (NE), north (N), southeast (SE), Yangtze River (YR), northwest (NW), central China (C), and Tibet Plateau (TP). The spatiotemporal variations of drought characteristics indicated that the drought count in NE and C was generally high. Southern China and NW had suffered long drought duration and extreme severity. The MK test results show that stations with significant drying trends mainly locate in SW, N, NW, and C. The severe drought frequency was very high in 1990s and 2000s. Furthermore, more attention should be paid to abnormal less precipitation in summer and abnormal high temperature in spring in SW, NE, N, and C. Besides, abnormal less precipitation is the main factor of drought in SE and YR in whole year. This study is anticipated to support the water resources management, and to promote the realization of environmental protection and agricultural production.
At the 62nd Meeting (2011) of the Marine Environment Protection Committee (henceforth MEPC), the IMO had adopted the proposed amendment adding to the MARPOL Annex Chapter Ⅵ making it mandatory the ...EEDI (Energy Efficiency Design Index) for new ships as well as the SEEMP (Ship Energy Efficiency Management Plan) for all ships. This was eventually for reducing GHG emissions from international shipping vessels, and has been effective since the 1st of January 2013 for ships weighing 400GT.
Notably, at the 70th MEPC, the plan to develop a roadmap for the comprehensive IMO strategy on reducing GHGs from ships was approved, and as such, the plans including its short-term, mid-term and long-term measures have been arranged in order to adopt the pertinent strategy by 2023.
Following the approved roadmap, at the 72
nd
MEPC (April, 2018), the first stage of reducing GHG emissions from ships was selected/passed as the Initial IMO strategy for the reduction of GHGs from ships (henceforth Initial IMO GHG Strategy), and at the 73
rd
MEPC (October, 2018), subsequent programs following the Initial IMO GHG Strategy were arranged.
In this paper, the following issues will be introduced and discussed 1) the initial IMO strategy for the reduction of GHG from ships, 2) the contents of the 73 ~ 74 MEPC meeting regarding the follow-up actions related GHG reduction programs until 2023 to be executed (including specific matters concerning the execution of potential short-term, mid-term and long-term measures) 3) the GHG reduction strategies, GHG response policies of IMO member states and 4) finally, trends in technological developments for GHG reduction from ships.
We demonstrate the hydrothermal synthesis of three dimension (3D) peony-like morphology of zinc gallate (ZnGa2O4), dominated by assembled nanosheets and applied as electrode material in ...electrochemical detection of N,N-dimethylmethanamide chemical. The crystalline, structural and compositional characterizations deduced the formation of high quality ZnGa2O4 with spinal crystal structure. Peony-like 3D ZnGa2O4 was benefited by a high surface area of ~62.3 m2 g−1, good pore distribution (mean pore diameter of ~23.3 nm) and large pore volume of ~0.3622 cm3 g−1. N,N-dimethylmethanamide chemical sensor based on peony-like 3D ZnGa2O4 electrode presented a linear curve in the working dynamic range of 1 nM−10 mM. Significantly improved chemical sensitivity of ~154.2 mA mM−1 cm−2 with low detection limit value of ~0.14 μM were achieved. The fabricated sensor based on peony-like 3D ZnGa2O4 electrode endorsed real sample analysis and ascertained the selectivity towards N,N-dimethylmethanamide chemical by analyzing a range of interfering analytes, viz. ethanol, tetrahydrofuran, methyl amine chemical.
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•Peony-like 3D ZnGa2O4 is applied as electrocatalytic material for N,N-dimethylmethanamide detection.•Peony-like 3D ZnGa2O4/SPE chemical sensor shows a good sensing behavior of ~154.2 mA mM−1 cm−2.•Fabricated sensor exhibits a high selectivity, reproducibility, and a long-term stability.
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