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[en] This PhD thesis is consisted of two major parts: precursor development for ALD and MOCVD applications as well as thin film deposition using ALD and MOCVD with self developed precursors. The first part of this work presents the synthesis, characterization and detailed thermal property investigations of different novel group IV and rare earth precursor classes (guandinate, guanidine and ketoiminate). The second part of this work presents the ALD and MOCVD depositions using various guanidinate precursors for forming corresponding metal oxide thin films. The overall motivation of this work is to fulfill the lack of precursors of rare earth and group IV elements for ALD and MOCVD applications that satisfy the stringent requirements for the modern microelectronic and optoelectronic technologies. The aspect of the precursor engineering part is focusing on influence of ligand sphere on precursors' chemical and thermal properties. In this way, we successfully introduced guanidine and ketoiminate as potential ligands for the precursor design. The thin film deposition part of this work is ALD of rare earth oxides and group IV oxides employing literature known compounds which were previously developed in our research group. The main focus was dedicated to the process optimization, the characterization of the structural, morphological, compositional and functional properties of the deposited thin films. Certain film properties were discussed comparatively with the corresponding thin films deposited with literature known precursors. It was already shortly demonstrated in Chapter 6 that the guanidine ligand showed potential interest as suitable ligand for precursor engineering. This titan guanidine precursor [Ti(NC(NMe2)2)4] (GD1) possesses higher thermal stability compared to its parent amide, [Ti(NMe2)4], while reactivity against water is not significantly affected. It could be very interesting to transfer this ligand for the precursor development of rare earth elements for ALD applications. A possible synthesis route is the salt metatheses route. It could be expected that the monodentate guanidine ligand would provide increased reactivity towards water, where the bulky guanidine ligands will shield the RE center providing self-limiting growth behavior. In Chapter 4 and 7, ALD of rare earth oxides and hafnium oxide using corresponding guanidinate precursors are in detail investigated. According to the measurements, these processes are true ALD processes with broad ALD windows, high growth per cycle in the saturated area. Furthermore, the rare earth guanidinate and hafnium guanidinate precursors exhibit matching ALD window in the temperature range of 200 - 225 C. This motivated us to deposite trinary oxide thin films (HfREOx) using corresponding precursor combinations.
[en] Objective: To investigate expression and clinical significance of hypoxia-inducible factor-1 alpha (HIF-1α) after TACE on rabbit VX2 liver neoplasms, and the correlation with tumor angiogenesis. Methods: Twenty four rabbits implanted liver VX2 tumors were randomly divided into 3 groups. Control group was administrated with 2 ml saline. TAE group was embolized with 0.5 to 0.8 ml ultra-fluid lipiodol. TACE group was embolized with 0.5 to 0.8 ml ultra-fluid lipiodol mixed with 2 mg Pirarubicin. Two weeks after treatment, HIF-1α, VEGF expression was detected by immunohistochemistry, and microvessel density(MVD) of the section marked with CD34 antibody was calculated. Results: The expressions of HIF-1α, VEGF and MVD in TAE group and TACE group were stronger than those in control group (P<0.05) . HIF-1α was positively correlated with VEGF and MVD (r=0.537, P<0.01; r=0.423, P<0.05). Conclusion: Significant overexpression of HIF-1α was found after TAE and TACE. HIF-1α plays an important role in the prognosis of liver neoplasms by up-regulating the expression of VEGF and increasing MVD. (authors)
[en] Objective: to analyze the technique success rate of endovascular stent-graft therapy in treating type B aortic dissection and to discuss the occurrence of both mild and severe complications including stroke, paraplegia, etc. Methods: The medical documents concerning endovascular stent-graft therapy for type B aortic dissection published from 1999 to 2009 were searched for through Medline. A total of 12 academic papers with 761 cases were collected. After making inclusion and exclusion criteria, the data obtained from the literature analyzed. Results: The analysis of all the available data showed that the technical success rate of endovascular stent-graft therapy for type B aortic dissection was 97.66%. The occurrence of minor complications, sever complications, stroke and paraplegia was 17.44%, 4.02%, 1.29% and 1.30%, respectively. The mortality was 3.55% within 30 days, and it was 4.08% during follow-up period (ranging from 12 months to 48.3 months). The occurrence of aortic rupture or retrograde aortic dissection formation in follow-up period was 3.06%. Conclusion: Endovascular stent-graft therapy for type B aortic dissection is technically feasible with fewer complications, nowadays it becomes the treatment of first choice. Nevertheless, as the follow-up time is rather short and the randomly controlled studies are lack, whether or not this technique carries statistically significant difference in therapeutic results when compared to other treatments needs to be further studied. (authors)
[en] To investigate the microbial community characteristics, antibiotic resistance genes (ARGs), and bioreactor effluent quality change under tetracycline (TC) and sulfamethoxazole (SMX) selection pressure, sequencing batch reactors (SBRs) were used with environmentally relevant concentration and high-level of TC and SMX concentrations (0, 5 ppb, 50 ppb and 10 ppm). Chemical oxygen demand (COD) and ammonia nitrogen (NH_4"+−N) removals appeared unchanged (p > 0.05) with 5 and 50 ppb, but decreased significantly with 10 ppm (p < 0.05). Extracellular polymeric substances (EPS) concentrations increased significantly with increasing TC or SMX concentrations (p < 0.05). High-throughput 16S rRNA gene sequencing results suggested that Proteobacteria, Actinobacteria and Bacteroidetes were the three most abundant phyla in sludge samples. The Actinobacteria percentages increased with increasing TC or SMX concentration, while Proteobacteria and Bacteroidetes decreased. The microbial diversity achieved its maximum at 5 ppb and decreased with higher concentrations. The total ARGs abundances in sludge increased with addition of TC or SMX, and the higher relative abundances were in the order of sul1 > tetG > sul2 > tetA > intI1 > tetS > tetC. Pearson correlation analysis showed most ARGs (tetA, tetC, tetG, tetK, tetM, sul1) were significantly correlated with intI1 (p < 0.01). - Highlights: • COD and NH_4"+−N removals significantly decrease under 10 ppm TC or SMX. • Activated sludge EPS concentrations increase with increasing TC or SMX concentrations. • TC and SMX affect the microbial community diversity of activated sludge. • Actinobacteria abundances increase with increase of TC or SMX concentration. • ARGs abundance increases with addition of TC or SMX.
[en] Organic photovoltaic (OPV) cells based on a poly(3-hexylthiophene) (P3HT):fullerene derivative [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) active layer with a bathocuproine (BCP)/8-hydroxyquinoline lithium (Liq) electron transport layer were fabricated to enhance their power conversion efficiency (PCE). Absorbance spectra showed that the absorbance intensity of the spectra for the P3HT:PCBM active layer with a Liq layer in the wavelength between 500 and 600 nm was enhanced due to the damage of the active layer. The PCE of the fabricated OPV cells with a Liq/BCP layer was significantly enhanced by up to 4.29% in comparison with that of OPV cells with a BCP or a Liq layer. - Highlights: • Organic photovoltaic cell with a bathocuproine (BCP)/8-hydroxyquinoline lithium (Liq) layer. • The BCP layer prevented the performance deterioration. • The efficiency of the photovoltaic cell with a BCP/Liq layer was enhanced
[en] Objective: To explore the effect of interventional ward to the development of interventional radiology. Methods: Investigation of the first class of the third grade hospitals in northeast region of China for the development status of interventional radiology in 2005 through questionnaires was undertaken. The hospitals were divided into two groups according to setting up interventional ward or not, together with comparative studies of number of doctors, sorts of interventional techniques and number of cases. Results: Altogether 52 3rd grade, 1st class hospitals have established interventional therapy, including with ward of 29 (55.8%)and no ward of 23 (44.2%); furthemore the average numbers of doctors in the forementioned two kinds of hospitals were 4.8 ± 1.7 vs 2.8 ± 1.5 (P<0.01) and the average numbers of procedure done were 481 vs 150(P<0.01), together with various sorts of technique 8 vs 5 (P<0.01), respectively. Conclusion: Establishment of interventional ward will benefit the development of interventional radiology. (authors)
[en] Objective: To evaluate the middle-long term effect of transcatheter arterial embolization (TAE) with pingyangmycin-lipiodol emulsion (PLE) in the treatment of hepatic hemangioma. Methods: Collected 116 hepatic hemangioma cases underwent interventional treatment with PLE in our hospital from April 2000 to September 2010. According to WHO solid tumors reference standard, evaluate clinical efficacy by the reduction rate of tumor; the changes of the clinical symptoms and complications were all recorded in the follow-up data. Results: 139 lesions of 116 cases were treated successfully. Follow-up 6 months to 10 years, the clinical symptoms disappeared in 79 cases, relieved in 6 cases and no change in 2 cases, effective rate is 97.7%. The size of the lesions reduced in different degrees. The effective rate of 6 months to 1 year, 1 to 3 years, 3 to 5 years and 5 to 10 years were 84.2%, 85.4%, 88.1% and 96.4% respectively. The largest cross-sectional areas of long-term follow-up 28 lesions were (30.54±23.98) cm2, (24.89±19.48) cm2, (20.73±17.78) cm2, (17.30±15.21) cm2 respectively, compared with preoperative [(89.44±67.93) cm2] respectively with a significant difference (P<0.05). There were no serious complications in all cases. Conclusion: TAE with PLE in hepatic hemangioma proves to be effective, safe and little side-effects. It has broad indications and is an ideal method in the treatment of hepatic hemangioma. (authors)
[en] This study investigated the reduction of antibiotic resistance genes (ARGs), intI1 and 16S rRNA genes, by advanced oxidation processes (AOPs), namely Fenton oxidation (Fe"2"+/H_2O_2) and UV/H_2O_2 process. The ARGs include sul1, tetX, and tetG from municipal wastewater effluent. The results indicated that the Fenton oxidation and UV/H_2O_2 process could reduce selected ARGs effectively. Oxidation by the Fenton process was slightly better than that of the UV/H_2O_2 method. Particularly, for the Fenton oxidation, under the optimal condition wherein Fe"2"+/H_2O_2 had a molar ratio of 0.1 and a H_2O_2 concentration of 0.01 mol L"−"1 with a pH of 3.0 and reaction time of 2 h, 2.58–3.79 logs of target genes were removed. Under the initial effluent pH condition (pH = 7.0), the removal was 2.26–3.35 logs. For the UV/H_2O_2 process, when the pH was 3.5 with a H_2O_2 concentration of 0.01 mol L"−"1 accompanied by 30 min of UV irradiation, all ARGs could achieve a reduction of 2.8–3.5 logs, and 1.55–2.32 logs at a pH of 7.0. The Fenton oxidation and UV/H_2O_2 process followed the first-order reaction kinetic model. The removal of target genes was affected by many parameters, including initial Fe"2"+/H_2O_2 molar ratios, H_2O_2 concentration, solution pH, and reaction time. Among these factors, reagent concentrations and pH values are the most important factors during AOPs. - Highlights: • AOPs including Fenton oxidation and UV/H_2O_2 process could reduce ARGs effectively. • Fenton oxidation is slightly more effective than UV/H_2O_2 process in ARG reduction. • Removal of ARGs by AOPs follows the first-order reaction kinetic model. • Selected ARGs and 16S rRNA genes exhibit similar change trends during AOPs.
[en] Acesulfame (ACE) is listed as an emerging contaminant due to its environmental persistence and wide occurrence in the environment. ACE can be degraded partially in the regular UV disinfection process but the eco-toxicity of its irradiation products remains unclear. This study focused on the possible oxidative status change in the liver of Carassius auratus exposed to ACE and its irradiation products. The UV degradation of ACE follows pseudo-first-order kinetics, and eight irradiation products were identified. Fish were exposed 7 days to 0.1 and 10 mg/L ACE (ACE group) and ACE after UV irradiance (ACE-UV group). The oxidative stress in fish liver exposed to ACE group had no distinct change. However, in the ACE-UV group, the quantity of ·OH was induced by 17.96–55% and the MDA content increased by 16.28–68.28% compared to control. Time-effect exposure in the ACE-UV group showed that in the first 3 days the quantity of ·OH reached its peak, causing severe inhibition of SOD and continuous inducement of GPx. GSH helped scavenge ·OH and decreased below control after 3 days. An increased toxicity of ACE after UV irradiance was observed and its transfer after into aquatic environment needs to be recognized as an environmental risk. - Highlights: • The oxidative status in liver of Carassius auratus exposed to ACE had no distinct change. • An increased oxidative stress of Crassius auratus was observed by exposed to ACE UV irradiance products. • ACE after UV irradiance is more eco-toxicity than ACE itself by inducing the accumulation of OH. • Eight UV irradiation products of ACE were identified.
[en] The methods of diagnostic imaging for pulmonary embolism is diversified. However, the different characteristic features of diagnostic imaging and diagnostic accuracy impressive influenced the choice of selection by clinicians. Furthermore, the principle and indication of interventional therapy would have great impending force on the outcomings. This article presents a comprehension of diagnostic imagings and interventional therapy for pulmonary embolization. (authors)