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Several methods have been proposed in recent years to counteract climate change and ocean acidification by removing CO2 from the atmosphere (Carbon Dioxide Removal). The most versatile and widely applicable of these methods is enhanced weathering of olivine, which is capable of removing billions of tons of CO2 from the atmosphere at moderate cost compared to the high cost of Carbon Capture and Storage (CCS). Despite its disadvantages, CCS is still the favored solution of many governments. Many misunderstandings of the potential of enhanced weathering persist. This paper addresses some of these misunderstandings, mainly caused by models which ignore established facts.

The regulations governing regional government today determine that the Deputy Regional Head is responsible to the Regional Head. The implication is that the financial position and protocol position of the Deputy Regional Head are often considered unbalanced compared to the Regional Head. A further consequence is the development of a less harmonious working relationship between the Regional Head and Deputy Regional Head. This tendency is reflected in, among others, the expression of the desire of the Deputy Regional Head to become a candidate for the Regional Head in the next election only moments after sitting in office. This situation makes the leadership of regional government not conducive. This paper tries to develop ideas regarding the importance of removing the position of Deputy Regional Head in question.

AbstractNitrate pollution in surface and groundwater is known to adversely affect human health, water quality and the health of aquatic ecosystems. Zero‐valent aluminium is a strong reductant for ions such as nitrate. In this study, its use in nitrate reduction efficiency was evaluated as a function of pH, aluminium dosage and aluminium particle size through a lab‐scale investigation. The most effective pH for complete nitrate removal, with an initial concentration of 14.0 ± 1.0 mg N/L, was found to be 13 ± 0.2. Under this condition, complete removal was achieved in 5 min, using aluminium particle size of 1–3 µm and aluminium‐to‐nitrate (NO3–‐N) ratio of 125. The 1–3 µm and 297–841 µm aluminium particles removed nitrate at a reaction rate constant (k) of 0.048 ± 0.017 (mg‐N/L)1.53/min and at 0.042 ± 0.014 (mg‐N/L)1.28/min, respectively. The use of smaller aluminium particles was found to be more effective for nitrate removal than large particles, and it was observed that for these particle sizes, aluminium dosages was less of a factor than any other experimental conditions evaluated.

AbstractEnvironmental regulation, increased pressure on water resources and rising cost for wastewater discharges make wastewater treatment for recycling an essential investment for many industries. Ammonia is a major pollutant in many industrial and agricultural wastewaters, and its elimination is essential for wastewater to be reused or meeting local discharge standards. In this study, the removal of ammonia from dilute aqueous solution has been investigated using sweep gas and vacuum membrane distillation (SGMD and VMD). Factors that affect the separation process such as feed and air flow rates, vacuum degree and feed temperature have been investigated. Overall, mass transfer coefficients (Kov) were calculated, and the results indicated that Kov for VMD is higher than that for SGMD under similar operation. Overall, ammonia mass transfer coefficient up to 12.06 × 10−5 and 5.63 × 10−5 m/s can be achieved for VMD and SGMD, respectively. The ammonia removal efficiency was enhanced by increasing sweep gas flow rate or by decreasing downstream pressure.

The analysis of policy-based party competition will not make serious progress beyond the constraints of (a) the unitary actor assumption & (b) a static approach to analyzing party competition between elections until a method is available for deriving reliable & valid time-series estimates of the policy positions of large numbers of political actors. Retrospective estimation of these positions in past party systems will require a method for estimating policy positions from political texts. Previous hand-coding content analysis schemes deal with policy emphasis rather than policy positions. We propose a new hand-coding scheme for policy positions, together with a new English language computer-coding scheme that is compatible with this. We apply both schemes to party manifestos from Britain & Ireland in 1992 & 1997 & cross validate the resulting estimates with those derived from quite independent expert surveys & with previous manifesto analyses. There is a high degree of cross validation between coding methods, including computer coding. This implies that it is indeed possible to use computer-coded content analysis to derive reliable & valid estimates of policy positions from political texts. This will allow vast volumes of text to be coded, including texts generated by individuals & other internal party actors, allowing the empirical elaboration of dynamic rather than static models of party competition that move beyond the unitary actor assumption. 4 Tables, 1 Figure, 21 References. Adapted from the source document.

This book provides extensive information on high-temperature H2S removal for integrated gasification combined cycle (IGCC) coarse gas, together with briefly introductions to the concept of clean coal technology, and to the mechanism and kinetics of hot coal gas desulfurizers. Readers will gain a comprehensive understanding of available control methods for high-temperature H2S removal in IGCC coarse gas and how the technology has been adopted by industry. As such, the book offers a unique resource for researchers and engineers in the fields of energy science and technology, environmental science and technology, and chemical engineering.

Existing approaches to measuring political disagreement from text data perform poorly except when applied to narrowly selected texts discussing the same issues and written in the same style. We demonstrate the first viable approach for estimating legislator-specific scores from the entire speech corpus of a legislature, while also producing extensive information about the evolution of speech polarization and politically loaded language. In the Irish Dáil, we show that the dominant dimension of speech variation is government–opposition, with ministers more extreme on this dimension than backbenchers, and a second dimension distinguishing between the establishment and anti-establishment opposition parties. In the U. S. Senate, we estimate a dimension that has moderate within-party correlations with scales based on roll-call votes and campaign donation patterns; however, we observe greater overlap across parties in speech positions than roll-call positions and partisan polarization in speeches varies more clearly in response to major political events.

This review collects the most theoretical and experimental data about the fundaments of ultrasonic cavitation and its application in the domain of water and drinking water treatment. It is describing the most important mechanism of acoustic cavitation based on "Hot spot theory" which is based on free radicals, especially hydroxyl radicals. The experimental examples are focused on organic micropollutants removal from wastewater and drinking water. There are many organic pollutants resistant to classical treatment flows in wastewater and drinking water treatment plants which means there must be updated with new technologies like Advanced Oxidation Processes (AOPs). Ultrasonication and advanced ultrasonication is one of these new approaches. Ultrasonication was the base of a new chemistry domain - sonochemistry and its development led to new and modern degradation methods of natural and industrial organic pollutants: natural organic matter, phenols, organochlorinated compounds, surfactants, etc. with high mineralization degree. Some examples are described below.

Pharmaceuticals and personal care products (PPCPs) are widely used on a daily basis. After their usage they reach the wastewater treatment plants (WWTPs). These compounds have different physico-chemical characteristics, which makes them difficult to completely remove in the WWTPs, througth conventional treatments. Currently, there is no legislation regarding PPCPs thresholds in effluent discharge. But, even at vestigial concentrations, these compounds enclose environmental risks due to, e.g., endocrine disruption potential. There is a need of alternative techniques for their removal in WWTPs. The main goal of this work was to assess the use of electrodialytic (ED) process to remove PPCPs from the effluent to be discharged. A two-compartment ED cell was used testing (i) the effluent position in the cell (anode and cathode compartment); (ii) the use of anion (AEM) and cation exchange membrane (CEM); (iii) the treatment period (6, 12 and 24 hours); (iv) effluent recirculation and current steps; (v) the feasibility of sequential treatments. Phosphorus (P) removal from effluent and energetic costs associated to the process were also evaluated. Five PPCPs were studied – caffeine (CAF), bisphenol A (BPA), 17 β-estradiol (E2), ethinyl estradiol (EE2) and oxybenzone (MBPh). The ED process showed to be effective in the removal when effluent is in the anode compartment. Oxidation is suggested to be the main removal process, which was between 88 and 96%, for all the compounds, in 6 hours. Nevertheless, the presence of intermediates and/or by-products was also observed in some cases. Effluent recirculation should have a retention time in the ED cell big enough to promote removal whereas the current steps (effluent in anode compartment) slightly increased removal efficiencies (higher than 80% for all PPCPs). The sequential set of ED treatment (effluent in anode compartment) showed to be effective during both periods with a removal percentage between 80 and 95% and 73 to 88% in the case of AEM and CEM, respectively. Again, the main removal process is strongly suggested to be oxidation in the anode compartment. However, there was an increase of BOD5 and COD, which might be explained by effluent spiking, these parameters limiting the effluent discharge. From these treatments, the use of AEM, enhanced the P removal from effluent to minimize risk of eutrophication. Energetic costs of the best set-up (6 hours) are approximately 0,8€/m3 of wastewater, a value considered low, attending to the prices of other treatment processes.