345 research outputs found


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    This dissertation presents the findings of a qualitative study examining needs of Chinese families with children with intellectual and developmental disabilities. The purpose of this dissertation is to inform the process of further developing the family support programs and opportunities that already exist in China and to assist in establishing best practices, as authorized by existing or proposed policy, through a qualitative explication of the family needs of Chinese families of children with IDD. Through focus group discussions and interviews, Chinese families expressed a vast array of needs. Three types of family needs emerged: (a) survival needs, (b) sufficiency needs, and (c) enhancement needs. Overall, this study develops a conceptual framework explaining the relationship among factors influencing family perceptions of their needs, family needs, and the resulting types of family support that are aligned with family needs and, ultimately, the delivery of family support to families. A discussion of the findings is provided and implications for practice, policy, and future research are discussed

    A Review on Progress in QSPR Studies for Surfactants

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    This paper presents a review on recent progress in quantitative structure-property relationship (QSPR) studies of surfactants and applications of various molecular descriptors. QSPR studies on critical micelle concentration (cmc) and surface tension (γ) of surfactants are introduced. Studies on charge distribution in ionic surfactants by quantum chemical calculations and its effects on the structures and properties of the colloids of surfactants are also reviewed. The trends of QSPR studies on cloud point (for nonionic surfactants), biodegradation potential and some other properties of surfactants are evaluated

    Unravelling the Correlation of Electronic Structure and Carrier Dynamics in CuInS\u3csub\u3e2\u3c/sub\u3e Nanoparticles

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    In this work, we report the direct correlation of photoinduced carrier dynamics and electronic structure of CuInS2 (CIS) nanoparticles (NPs) using the combination of multiple spectroscopic techniques including steady-state X-ray absorption spectroscopy (XAS), optical transient absorption (OTA), and X-ray transient (XTA) absorption spectroscopy. XAS results show that CIS NPs contain a large amount of surface Cu atoms with ≪four-coordination, which is more severe in CIS NPs with shorter nucleation times, indicating the presence of more Cu defect states in CIS NPs with smaller size particles. Using the combination of OTA and XTA spectroscopy, we show that electrons are trapped at states with mainly In or S nature while holes are trapped in sites characteristic of Cu. While there is no direct correlation of ultrafast trapping dynamics with NP nucleation time, charge recombination is significantly inhibited in CIS NPs with larger particles. These results suggest the key roles that Cu defect sites play in carrier dynamics and imply the possibility to control the carrier dynamics by controlling the surface structure at the Cu site in CIS NPs