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6b. Wasi (2 points). Fatigue cracking susceptibility is not caused by

Q2. Sullivan (15 points). In class, we discussed the effects of gradation, particle texture, clay content, angularity, and specific gravity on fine aggregate testing and their effects on mix design and ultimate mixture performance. Discuss factors to be mindful of when measuring and interpreting the following properties of fine aggregates and how these properties may affect mix performance: fine aggregate angularity, sand equivalency, and specific gravity.  

4f. Optimum asphalt content for Superpave mix design is selected at:

Q3. Sullivan (15 points). Briefly describe the Superpave mix design method. In your answer, highlight how the Superpave mix design method addresses rutting and cracking performance. In your opinion, what are Superpave’s biggest strengths and areas where the most improvement is needed?

6a. Wasi (2 points). Rutting susceptibility is not caused by

Which statements about integrated rate laws are correct?

This question is about reaction kinetics, integrated rate laws, and temperature dependence. A reaction A -> products was studied by measuring [A] over time. The data are: time (min): 5, 10, 15 [A] (M): 0.38090, 0.23103, 0.14013 A separate first-order reaction B -> products has k = 9.60 x 10^-3 s^-1 at 45 degrees C. A second-order reaction C -> products has k = 1.80 x 10^-3 M^-1 s^-1 at 27 degrees C. Finally, for another reaction, increasing the temperature from 298 K to 310 K increases the rate constant by a factor of 2.50. A. Use the A data to decide whether the reaction is most consistent with zero, first, or second order. B. Calculate the first-order rate constant for A -> products using the data. C. For B -> products, calculate the time required for [B] to fall to 6.25 percent of its initial value. D. For the second-order reaction C -> products, calculate [C]0 if the half-life is 214 s. E. Estimate the activation energy for the reaction whose rate constant increases by a factor of 2.50 from 298 K to 310 K. F. Interpret why a reaction with a larger activation energy is more temperature-sensitive. G. Explain whether a catalyst would change the equilibrium constant for A -> products.   Please do not enter anything in the text box below, but rather answer in writing on paper.

Lysine can be described as a molecule with three ionizable groups. Use the following pKa values for the sequential deprotonation states: Lys2+ Lys+ + H+, pKa1 = 2.2 Lys+ Lys0 + H+, pKa2 = 9.0 Lys0 Lys- + H+, pKa3 = 10.5 A buffer at 25 degrees C has pH = 9.80 and total lysine concentration Ctotal = 0.150 M. Assume ideal behavior.   A. Calculate [H+] and [OH-]. B. Calculate the ratios [Lys+]/[Lys2+], [Lys0]/[Lys+], and [Lys-]/[Lys0]. C. Calculate the fractional abundance of each protonation state. D. Calculate the concentration of each protonation state. E. Calculate the average charge per lysine molecule at pH 9.80. F. Estimate the Na+ concentration needed for electroneutrality if NaOH was used to adjust the pH. Explain what this value means. G. Which two protonation states dominate at pH 9.80, and why?   Please do not enter anything in the text box below, but rather answer in writing on paper.

Mettez les verbes entre parenthèses au présent. Cherchez tous les mots que vous ne connaissez pas dans le dictionnaire. 100 POINTS  ô  é  è  ê  à  â  ç  ï  î  ù  û  œ  Le soleil (briller) [1] et les enfants (jouer) [2]. Tu (guérir) [3], mais tu (maigrir) [4]. Le professeur (parler) [5] et les étudiants (écouter) [6]. Ma sœur (montrer) [7] à mes parents qu’elle (dessiner) [8]. À quelle heure (atterrir) [9] ton avion ? Le professeur (expliquer) [10] la leçon et les étudiants (étudier) [11]. Nous (habiter) [12] dans une grande maison à Paris. On (rougir) [13] quand on (parler) [14] à une personne qu’on (aimer) [15]. Qui (bénir) [16] les repas dans ta famille ? Dieu (pardonner) [17] nos péchés. Chaque vendredi, je (rencontrer) [18] mes amis et nous (déjeuner) [19]. Les parents (punir) [20] leurs enfants quand ils (désobéir) [21]. On (choisir) [22] des classes faciles à l’université. Tu (quitter) [23] ta maison et tu (monter) [24] dans ta voiture. Quand je (manger) [25] beaucoup, je (grossir) [26] vite. Nous (fermer) [27] nos livres et nous (laisser) [28] tout sur la table. On (réussir) [29] toujours quand on (travailler) [30] beaucoup. Il (pleurer) [31] quand il ne (réussir) [32] pas. Les voitures (ralentir) [33] quand les gens (passer) [34] la rue. Vous (saluer) [35] tous vos amis dans la classe de français. Quand le spectacle (finir) [36], tous les spectateurs (applaudir) [37]. Le professeur (enseigner) [38] la leçon et les étudiants (écouter) [39]. Mes enfants (grandir) [40] vite.

When lead aprons are worn, and only one OSL dosimeter, the radiation monitoring device should be placed at the: