Laser ablation in liquid of Germanium in externally applied electric fields

Title from PDF of Title page, viewed on March 10, 2014VitaThesis advisor: Michael KrugerIncludes bibliographic references (pages 42-45)Thesis (M.S.)--Dept. of Physics. University of Missouri--Kansas City, 2013Laser ablation in liquids has been proven to be an effective path to synthesize nanomaterials.1 Laser ablation in liquids provides unique advantages since materials are fabricated under nonequilibrium, high-pressure, high-temperature conditions. In addition, it allows for varying many parameters (e.g. laser fluence, liquid) to help control synthesis. Laser ablation in liquids with an externally applied electric field extends the traditional Laser ablation in liquids approach, and in the only published report on this topic, has been shown to control the morphology, size, chemical composition and structure of the samples.2 In this thesis, the effect of electric fields on Laser ablation in liquids of germanium targets is studied. The aim is to better understand the role of an externally applied electric field in the ablation process and on the ablation products.Abstract -- Approval -- Illustrations -- Tables -- Acknowledgements -- Introduction -- Experiment procedures -- Fundamental theories -- Data collection and analysis -- Conclusion -- Bibliograph

Coordination of UFLS and UFGC by Application of D-SMES

In this paper, the authors studied the coordination of under frequency load shedding (UFLS) and under frequency governor control (UFGC) by applying the distributed superconducting magnetic energy storage (D-SMES) devices. The active power of D-SMES device is controlled to eliminate the initial rapid frequency drop and allow time for the full action of UFGC to take over. The reactive power of D-SMES is controlled to stabilise the local bus voltage. The research results show that D-SMES devices can damp the quick dropping of system frequency and hold it waiting for the full activation of system spinning reserve. D-SMES can help the governors output their maximum reserve before UFLS drops more load

Growth of Semiconductor Thin Films by Pulsed Laser Deposition

Title from PDF of title page, viewed on January 27, 2017Dissertation advisor: Jerzy M. WrobelVitaIncludes bibliographical references (pages 90-95)Thesis (Ph.D.)--Department of Physics and Astronomy and Department of Chemistry. University of Missouri--Kansas City, 2016Pulsed ultraviolet light from a XeF excimer laser was used to grow thin films of zinc oxide and tin dioxide on (111) p-type silicon wafers within a versatile high vacuum laser deposition system. This pulsed laser deposition system was self-designed and self-built. Parameters such as pressure, target temperature, and distance from the target to the substrate can be adjusted in the system. Scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction spectroscopy, Raman spectroscopy and ellipsometry were used to analyze the structures and properties of ZnO and SnO2 thin films. The critical temperature required to fabricate a crystalline ZnO thin film by pulsed laser deposition was found and has been confirmed. For the SnO2 thin film, the critical temperature required to generate a crystalline structure could not be found because of the temperature limit of the substrate heater used in the experiment. In SnO2 thin films, thermal annealing has been used to convert into crystalline structure with (110), (101) and (211) orientations. After fabricating the amorphous SnO2 thin films, they were put into an oven with specific temperatures to anneal them. The minimum annealing temperature range was found for converting the amorphous SnO2 thin films into SnO2 thin films with a crystalline structure. Thermal annealing has also been applied to some amorphous ZnO thin films which were fabricated under the critical temperature required to produce crystalline ZnO thin films. The minimum annealing temperature range for amorphous ZnO thin films was found and only one orientation (002) shown after annealing. Laser annealing technology has also been applied for converting both amorphous ZnO and SnO2 thin films, and results show that this method was not well suited for this attempt. ZnO thin films and SnO2 thin films with a crystalline structure have inportant widely used in industry, for example, application in devices such as solar cells and UV or blue-light-emitting devices. The aim of this research is to help improving the manufacturing process of ZnO and SnO2 thin films.Introduction -- Background -- Data collection and analysi

Faster randomized partial trace estimation

We develop randomized matrix-free algorithms for estimating partial traces. Our algorithm improves on the typicality-based approach used in [T. Chen and Y-C. Cheng, Numerical computation of the equilibrium-reduced density matrix for strongly coupled open quantum systems, J. Chem. Phys. 157, 064106 (2022)] by deflating important subspaces (e.g. corresponding to the low-energy eigenstates) explicitly. This results in a significant variance reduction for matrices with quickly decaying singular values. We then apply our algorithm to study the thermodynamics of several Heisenberg spin systems, particularly the entanglement spectrum and ergotropy

EAF Voltage Flicker Mitigation by FACTS/ESS

One of the problems caused by an electrical arc furnace (EAF) is voltage fluctuation from the variations of the active and reactive furnace load, which are known as voltage flickers. In this paper, voltage flicker mitigation results by different FACTS and energy storage systems (ESS) were presented. The system X/R ratio looking from the point of common coupling, which has a special impact on the effectiveness of active compensation, was discussed. The study has clarified the misunderstanding of how the system X/R ratio should be calculated. The study showed that FACTS with ESS could play a better role than reactive power alone in mitigating EAF voltage flickers

Plant buffering against the high-light stress-induced accumulation of CsGA2ox8 transcripts via alternative splicing to finely tune gibberellin levels and maintain hypocotyl elongation

Ajuts: this study was supported by The National Key Research and Development Program of China (2019YFD1000300), the International Postdoctoral Exchange Fellowship Program from the China Postdoctoral Council (20170053), the Technology System Construction of Modern Agricultural Industry of Shanghai (19Z113040008), and the Presidential Foundation of Guangdong Academy of Agricultural Sciences (BZ201901).In plants, alternative splicing (AS) is markedly induced in response to environmental stresses, but it is unclear why plants generate multiple transcripts under stress conditions. In this study, RNA-seq was performed to identify AS events in cucumber seedlings grown under different light intensities. We identified a novel transcript of the gibberellin (GA)-deactivating enzyme Gibberellin 2-beta-dioxygenase 8 (CsGA2ox8). Compared with canonical CsGA2ox8.1, the CsGA2ox8.2 isoform presented intron retention between the second and third exons. Functional analysis proved that the transcript of CsGA2ox8.1 but not CsGA2ox8.2 played a role in the deactivation of bioactive GAs. Moreover, expression analysis demonstrated that both transcripts were upregulated by increased light intensity, but the expression level of CsGA2ox8.1 increased slowly when the light intensity was >400 µmol·m −2 ·s −1 PPFD (photosynthetic photon flux density), while the CsGA2ox8.2 transcript levels increased rapidly when the light intensity was >200 µmol·m −2 ·s −1 PPFD. Our findings provide evidence that plants might finely tune their GA levels by buffering against the normal transcripts of CsGA2ox8 through AS

Single cell and bulk transcriptome analysis identified oxidative stress response-related features of Hepatocellular Carcinoma

Background: Hepatocellular Carcinoma (HCC) is a common lethal digestive system tumor. The oxidative stress mechanism is crucial in the HCC genesis and progression.Methods: Our study analyzed single-cell and bulk sequencing data to compare the microenvironment of non-tumor liver tissues and HCC tissues. Through these analyses, we aimed to investigate the effect of oxidative stress on cells in the HCC microenvironment and identify critical oxidative stress response-related genes that impact the survival of HCC patients.Results: Our results showed increased oxidative stress in HCC tissue compared to non-tumor tissue. Immune cells in the HCC microenvironment exhibited higher oxidative detoxification capacity, and oxidative stress-induced cell death of dendritic cells was attenuated. HCC cells demonstrated enhanced communication with immune cells through the MIF pathway in a highly oxidative hepatoma microenvironment. Meanwhile, using machine learning and Cox regression screening, we identified PRDX1 as a predictor of early occurrence and prognosis in patients with HCC. The expression level of PRDX1 in HCC was related to dysregulated ribosome biogenesis and positively correlated with the expression of immunological checkpoints (PDCD1LG2, CTLA4, TIGIT, LAIR1). High PRDX1 expression in HCC patients correlated with better sensitivity to immunotherapy agents such as sorafenib, IGF-1R inhibitor, and JAK inhibitor.Conclusion: In conclusion, our study unveiled variations in oxidative stress levels between non-tumor liver and HCC tissues. And we identified oxidative stress gene markers associated with hepatocarcinogenesis development, offering novel insights into the oxidative stress response mechanism in HCC