Browsing by Author "Zhang, Li"
Now showing 1 - 4 of 4
Results Per Page
Sort Options
Item A general kinetic model: Kinetics and atomic-scale mechanisms of feldspar dissolution(2008) Zhang, Li; Luttge, AndreasThis thesis presents a general kinetic model and its application to feldspar dissolution. In the framework of Monte Carlo methods, the model simulates the stochastic processes of feldspar dissolution by incorporating bond breakage, bond formation, surface diffusion, and the detachment and attachment of various mineral-forming ions. Quantum mechanical calculations are implemented to quantify the energies required to break and form Si-O-Si and Si-O-Al bonds. Empirical interatomic potential modeling is used to examine the relaxation of the feldspar's surface structure from the ideal bulk structure. The kinetic model incorporates the proper crystallographic surface structures, emphasizing the essential role of dynamics of neighboring sites on the crystal surface. The application of the general kinetic model to feldspar dissolution elucidates the kinetic patterns observed in experimental observations and improves our fundamental understanding of feldspar dissolution. In addition, we use the model with the appropriate change in parameterization to investigate the morphological evolution of a (001) surface of barite etched in pure water. The generation of two sets of oppositely-oriented triangular etch pits in consecutive atomic layers validates the model's efficiency. It is the first stochastic treatment out of numerous studies concerning barite dissolution to address this unique pit morphology. We further extend the model from abiotic water-mineral interactions and apply it to microbe-water-rock interactions in order to explore this subject as a complementary approach.Item Dynamic Spin-Lattice Coupling and Nematic Fluctuations in NaFeAs(American Physical Society, 2018) Li, Yu; Yamani, Zahra; Song, Yu; Wang, Weiyi; Zhang, Chenglin; Tam, David W.; Chen, Tong; Hu, Ding; Xu, Zhuang; Chi, Songxue; Xia, Ke; Zhang, Li; Cui, Shifeng; Guo, Wenan; Fang, Ziming; Liu, Yi; Dai, PengchengItem The origin of bladder cancer from mucosal field effects(Cell Press, 2022) Bondaruk, Jolanta; Jaksik, Roman; Wang, Ziqiao; Cogdell, David; Lee, Sangkyou; Chen, Yujie; Dinh, Khanh Ngoc; Majewski, Tadeusz; Zhang, Li; Cao, Shaolong; Tian, Feng; Yao, Hui; Kuś, Paweł; Chen, Huiqin; Weinstein, John N.; Navai, Neema; Dinney, Colin; Gao, Jianjun; Theodorescu, Dan; Logothetis, Christopher; Guo, Charles C.; Wang, Wenyi; McConkey, David; Wei, Peng; Kimmel, Marek; Czerniak, BogdanWhole-organ mapping was used to study molecular changes in the evolution of bladder cancer from field effects. We identified more than 100 dysregulated pathways, involving immunity, differentiation, and transformation, as initiators of carcinogenesis. Dysregulation of interleukins signified the involvement of inflammation in the incipient phases of the process. An aberrant methylation/expression of multiple HOX genes signified dysregulation of the differentiation program. We identified three types of mutations based on their geographic distribution. The most common were mutations restricted to individual mucosal samples that targeted uroprogenitor cells. Two types of mutations were associated with clonal expansion and involved large areas of mucosa. The α mutations occurred at low frequencies while the β mutations increased in frequency with disease progression. Modeling revealed that bladder carcinogenesis spans 10–15 years and can be divided into dormant and progressive phases. The progressive phase lasted 1-2 years and was driven by β mutations.Item Weaker nematic phase connected to the first order antiferromagnetic phase transition inᅠSrFe2As2ᅠcompared toᅠBaFe2As2(American Physical Society, 2019) Tam, David W.; Wang, Weiyi; Zhang, Li; Song, Yu; Zhang, Rui; Carr, Scott V.; Walker, H.C.; Perring, Toby G.; Adroja, D.T.; Dai, PengchengUnderstanding the nature of the electronic nematic phase in iron pnictide superconductors is important for elucidating its impact on high-temperature superconductivity. Here we use transport and inelastic neutron scattering to study spin excitations and in-plane resistivity anisotropy in uniaxial pressure detwinned BaFe2As2 and SrFe2As2, the parent compounds of iron pnictide superconductors. While BaFe2As2 exhibits weakly first-order tetragonal-to-orthorhombic structural and antiferromagnetic (AF) phase transitions below Ts>TN≈138K, SrFe2As2 has strongly coupled first-order structural and AF transitions below Ts=TN≈210K. We find that the direct signatures of the nematic phase persist to lower temperatures above the phase transition in the case of SrFe2As2 compared to BaFe2As2. Our findings support the conclusion that the strongly first-order nature of the magnetic transition in SrFe2As2 weakens the nematic phase and resistivity anisotropy in the system.