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When bilingual teachers are first hired, many say they are pressured to teach material only in English (Menken, 2008). Removing instruction in a child’s native language is not likely to improve scores on English standardized tests (Rolstad, Mahoney, & Glass, 2005), and long term, English-Only instruction reduces academic success and reduces graduation rates (Iddings, Combs, & Moll, 2012). This chapter looks at bilingual classrooms in a Texas school district, through classroom observations, interviews, and a large-scale survey seeking to answer the question, what do officially bilingual classrooms look like when they operate monolingually? Results showed that administrators exerted pressure, and teachers used methods they expected not to work. Some bilingual classrooms had teachers who either could not speak Spanish, or chose not to. Because classrooms operated without the legally required amount of first-language instruction, the district’s “bilingual” programs undermined accountability data while harming emergent bilinguals. Teacher educators have not prepared bilingual teachers for the reality of anti-bilingual schools. New teachers need to know how to not only implement research-based instruction but also defend their instructional choices. Wherever lawmakers, agencies, and administrators have allowed transitional bilingual programs to become de facto monolingual, there may be a role for colleges of education to play, monitoring, assisting, and, if necessary, publicizing lack of compliance. Study findings are limited to one specific district; even in districts with similar phenomena, the manner in which a bilingual program ceases to be bilingual will vary substantially.

Conductive coatings form the basis of a common anode system used in the cathodic protection of steel in concrete. One of the properties required by such a coating is a low sheet resistance (square resistance). This, together with the protection current density and anode connection geometry, determines the uniformity of the current distribution over the concrete surface. It is shown that the sheet resistance may be determined using a non‐destructive test employing a collinear four‐probe array. When a current (I), passed between the outer probes of an equally spaced four‐probe array, induces a voltage difference (δV) between the inner probes, the sheet resistance is given by (pgr;/ln2)x(dgr;V/I). The validity of the measured values may be assessed by the absence of any sensitivity to probe orientation and spacing. This technique may be used in the assessment of the quality of installed conductive coating anodes. The sheet resistance will depend on factors such as the thickness and age of the installed coating.

This work seeks to present a systematic study that aimed to provide quantitative understanding of the fundamental factors that influence the chloride threshold of pitting corrosion of steel in concrete, by conducting a set of laboratory tests to assess the corrosion potential (E_corr) and pitting potential (E_pit) of steel coupons in simulated concrete pore solutions.

With the aid of artificial neural network, the laboratory data were used to establish a phenomenological model correlating the influential factors (total chloride concentration, chloride binding, solution pH, and dissolved oxygen (DO) concentration) with the pitting risk (characterized by E_corr−E_pit). Three‐dimensional response surfaces were then constructed to illustrate such predicted correlations and to shed light on the complex interactions between various influential factors.

The results indicate that the threshold [Cl⁻]/[OH⁻] of steel rebar in simulated concrete pore solutions is a function of DO concentration, pH and chloride binding, instead of a unique value.

The limitations and implications of the research findings were also discussed.

This research could have significant practical implications in predicting the service life of new or existing reinforced concrete in chloride‐laden environments.

This study further advances the knowledge base relevant to the chloride‐induced corrosion of steel rebar in concrete.

This chapter discusses a family writing project that a third and fourth grade English Language Development (ELD) teacher created with and for her students and families. The project took place within a state with English-only mandates, restrictive curriculum, and harsh anti-immigrant politics. The author outlines the ways that the project worked to disrupt the restrictive policies to honor and celebrate the cultures, languages, and ways of knowing and students and families by inviting them to write and share stories from their lived experiences.

BY mid‐September when these words appear there may be the first touch of frost in the mornings : summer is irrecoverably over. There is yet, a week ahead, the Library Association Conference and not a few older librarians, who have a life‐long memory of Autumn conferences, are happy that we no longer hold them in May, that adolescent, variable month, but are able to catch again in the season of mists and mellow fruitfulness the pleasures we have had in our summer holidays this perfect year. The irony of it lies in the fact that there is precious little holiday in today's conference week ; we do not even have an excursion on the Friday. Such frivolities are beyond the great gatherings of multilateral interests that assemble. Time, too, has become almost sordidly precious.

The purpose of this paper is to provide a modeling perspective relevant to the use of cathodic prevention (CPre) for unconventional concrete in salt‐laden environment.

Based on the experimentally obtained concrete resistivity and chloride diffusion coefficient data, numerical studies with the Nernst‐Planck equations were conducted to investigate the influence of applied voltage (magnitude, direction, and interruption), surface chloride concentration, and concrete mix design on the effectiveness of cathodic prevention and the distribution of ionic species in protected concrete.

The modeling results revealed that the direction of applied electric voltage has significant effect on the distributions of electrical potential and hydroxyl ions in the reinforced concrete, confirming the benefits of cathodic prevention in significantly increasing hydroxyl concentration near rebar and in slowing down the ingress of chloride ingress into concrete. The performance of intermittent CPre was found to be constrained by the variations in concrete resistance from the anode to the cathode. The model was also useful in illustrating the temporal and spatial evolutions on rebar surface in terms of oxygen, hydroxyl and chloride concentrations and electrical potential of top rebar, as well as such evolutions in concrete domain in terms of concrete resistivity and current density for each mix design.

The results reported herein shed light on the fundamental processes defining the performance of CPre for new unconventional concrete in salt‐laden environment.

The purpose of this paper is to present the results of a two-year long study carried out in order to evaluate the corrosion performance of mild steel bare bars (BB) and epoxy-coated rebar (ECR) in concrete under a simulated harsh environment of chlorides.

The blocks are subjected to Southern Exposure testing. The electrochemical impedance spectroscopy (EIS), linear polarization resistance (LPR) and Tafel plot are performed to measure the polarization resistance and corrosion current densities of these rebars. Knife-peel test was performed to assess the adhesion between epoxy and underlying steel after two years of exposure.

Mild steel BB showed a high corrosion current density of 1.24 µA/ cm² in Tafel plots and a very low polarization resistance of 4.5 kΩ cm² in LPR technique, whereas very high charge transfer resistance of 1672 and 1675 kΩ cm² is observed on ECR and ECR with controlled damage (ECRCD), through EIS technique, respectively. EIS is observed to be a suitable tool to detect the defects in epoxy coatings. After two years of immersion in 3.89 percent NaCl⁻ solution, the mild steel BB were severely corroded and a considerable weight loss was observed, whereas under heavy chloride attack, ECR showed no deterioration of epoxy coating and neither any corrosion of underlying steel. Results of this study show that the durability of reinforced concrete (RC) structures with respect to corrosion could be enhanced by using ECR, especially in harsh climatic conditions.

The corrosion performance of mild steel and ECR in concrete under a simulating splash zone environment is evaluated. EIS was used to evaluate the health of epoxy and corrosion state of underneath steel rebars. EIS was able to detect the defects in epoxy. The durability of RC structures could be enhanced in harsh climate regions by using ECR.

As it is widely known, corrosion constitutes a major deterioration factor for reinforced concrete (RC) structures which are located on coastal areas. This phenomenon combined with repeated loads, as earthquake events, negatively affects their service life. Moreover, microstructure of steel reinforcing bars has significant impact either on their corrosion resistance or on their fatigue life.

In the present manuscript an effort has been made to investigate the effect of corrosive factor on fatigue response for two types of steel reinforcement; Tempcore steel reinforcing bars and a new generation dual phase (DP) steel reinforcement.

The findings of this experimental study showed that DP steel reinforcement led to better results regarding its capacity to bear repeated loads to satisfactory degree after corrosion, although this type of steel has less stringent mechanical properties.

Additionally, a fatigue damage material indicator is proposed as a parameter that could rank material quality and its suitability for a certain application. The results of this investigation showed that the fatigue damage indicator can be used as an appropriate index in order to evaluate the overall performance of materials, in terms of strength and ductility capacity.

This work aims to demonstrate the use of electrochemical chloride extraction (ECE) to remove chloride ions away from the steel rebar in chloride-contaminated mortar and to mitigate the corrosion of the embedded steel.

To simulate salt contamination in concrete, sodium chloride was added at 0.5 per cent by weight of cement in the fresh mortar featuring a water-to-cement ratio of 0.45. The ECE treatments were varied at two electrical current densities (1 and 5 A/m²), using two electrolytes (0.1M NaOH and 0.1M Na₃BO₃ solutions) and for two periods (2 and 4 weeks). The average free chloride concentration in cement mortars before and after ECE treatment was quantified using a customized chloride sensor, whereas the spatial distribution of relevant elements was obtained using energy-dispersive X-ray spectroscopy. The effect of ECE treatment on the electric resistivity of mortar and the corrosion resistance of steel rebar was investigated by electrochemical impedance spectroscopy and potentiodynamic polarization measurements, respectively.

The experimental results reveal that the ECE treatment was effective in removing chlorides and in improving electric resistivity and compressive strength of the mortar, when using the sodium borate solution as the electrolyte. In this case, a 4-week ECE treatment at 1 A/m² decreased the free chloride content in the mortar by 70 per cent, significantly increased the Ca/Si ratio in the mortar near rebar, led to a more refined and less permeable microstructure of the mortar and significantly improved its compressive strength. The ECE treatment was able to halt the chloride-induced corrosion of steel rebar by passivation. A 4-week ECE treatment at 1 A/m² using sodium hydroxide and sodium borate solutions decreased the corrosion rate of rebar by 36 and 34 per cent, respectively.

This electrochemical rehabilitation of steel-reinforced concrete under chloride-contaminated condition is very effective in prolonging its service life.

This study aims to evaluate the protection performance of zinc as sacrificial anode for ABS A steel in the presence of H₂S under different temperatures, pH and salinities.

In this paper, weight loss measurements and electrochemical measurements are used to evaluate the corrosion degree of zinc and ABS A steel.

Under the conditions involved in this work, it is shown that zinc is a nice sacrificial anode with the reason of its stable potential and excellent anode current efficiency according to the relevant standard. And it is also found that the hydrogen evolution does not occur on ABS A steel specimens. The potential difference between cathode and anode is suitable; thus, it can be concluded that each steel is well protected.

To the best of the authors’ knowledge, no other study has analyzed the protection mechanism and effect of zinc as sacrificial anode in H₂S-containing environments under high temperature at present.