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Over the past several decades, green chemistry has gained prominence in chemistry education. However, the development of green chemistry curricula has not reached all levels of education equally, focusing mainly on elective and upper division courses. We deliberately focused our green chemistry curriculum redesign on a high enrollment introductory general chemistry laboratory course at the University of California, Berkeley. We developed over 30 new experiments that introduced students to green chemistry concepts and applications, while maintaining canonical general chemistry learning goals. The context of the curriculum and required course assignments encouraged students to use green chemistry principles to explore and solve real-world problems. After completing this redesigned course, we hypothesized that students would value green chemistry and feel more confident in their green chemistry knowledge. We developed new methods to measure students’ attitudes toward and understanding of green chemistry as a system instead of isolated reactions or processes. These assessments allowed us to better understand both the progression and limitations in student green chemistry and systems-thinking. Since over 2000 students complete the laboratory course each year, we used a combination of fixed response items and free response items from online surveys and in-class assignments and exams. This approach allowed efficient assessment of thousands of students, while still gaining valuable and nuanced views of student understanding and attitudes. These assessments indicated that the new general chemistry laboratory curriculum succeeded in providing an environment in which students learned green chemistry concepts and realized that chemistry has connections to their future courses and professions.

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CCQM-K120.a comparison involves preparing standards of carbon dioxide in air which are fit for purpose for the atmospheric monitoring community, with stringent requirements on matrix composition and measurement uncertainty of the CO2 mole fraction. This represents an analytical challenge and is therefore considered as a Track C comparison. The comparison will underpin CMC claims for CO2 in air for standards and calibrations services for the atmospheric monitoring community, matrix matched to real air, over the mole fraction range of 250 μmol/mol to 520 μmol/mol. CCQM-K120.b comparison tests core skills and competencies required in gravimetric preparation, analytical certification and purity analysis. It is considered as a Track A comparison. It will underpin CO2 in air and nitrogen claims in a mole fraction range starting at the smallest participant's reported expanded uncertainty and ending at 500 mmol/mol. Participants successful in this comparison may use their result in the flexible scheme and underpin claims for all core mixtures This study has involved a comparison at the BIPM of a suite of 44 gas standards prepared by each of the participating laboratories. Fourteen laboratories took part in both comparisons (CCQM-K120.a, CCQM-K120.b) and just one solely in the CCQM-K120.b comparison. The standards were sent to the BIPM where the comparison measurements were performed. Two measurement methods were used to compare the standards, to ensure no measurement method dependant bias: GC-FID and FTIR spectroscopic analysis corrected for isotopic variation in the CO2 gases, measured at the BIPM using absorption laser spectroscopy. Following the advice of the CCQM Gas Analysis Working Group, results from the FTIR method were used to calculate the key comparison reference values. KEY WORDS FOR SEARCH FTIR, CO2, GC-FID, Carbon dioxide at background level, Carbon dioxide at urban level, Delta Ray, CO2 gas standards Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCQM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

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Let ϕ(z) = (ϕ1(z),…,ϕn(z)) be a holomorphic self-map of B and ψ(z) a holomorphic function on B, where B is the unit ball of ℂn. Let 0 < p, s < +∞, -n - 1 < q < +∞, q+s > -1 and α ≥ 0, this paper characterizes boundedness and compactness of weighted composition operator Wψ,ϕ induced by ϕ and ψ between the space F(p, q, s) and α-Bloch space [Formula: see text].

In this paper, we discuss some algebraic properties of Toeplitz operators with radial symbols on the Bergman space of the unit ball in C n . We first determine when the product of two Toeplitz operators with radial symbols is a Toeplitz operator. Next, we investigate the zero-product problem for several Toeplitz operators with radial symbols. Also, the corresponding commuting problem of Toeplitz operators whose symbols are of the form ξ k ϕ is studied, where k ∈ Z n and ϕ is a radial function. (2000). Primary 47B35; Secondary 32A36. Mathematics Subject Classification