High-voltage direct current (HVDC) is a commonly used technology for long-distance power transmission, due to its low resistive losses and low costs. In this paper, a novel distributed controller for multi-terminal HVDC (MTDC) systems is proposed. Under certain conditions on the controller gains, it is shown to stabilize the MTDC system. The controller is shown to always keep the voltages close to the nominal voltage, while assuring that the injected power is shared fairly among the converters. The theoretical results are validated by simulations, where the affect of communication time-delays is also studied.

QC 20150519

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A series of dinuclear cycloplatinated(II) complexes with general closed formula of [Pt 2 Me 2 (C^N) 2 (μ-P^P)] (C^N = 2-vinylpyridine (Vpy), 2,2′bipyridine N-oxide (O-bpy), 2-(2,4-difluorophenyl)pyridine (dfppy); P^P = 1,1bis(diphenylphosphino)methane (dppm), N,N-bis(diphenylphosphino)amine (dppa)) are reported. The complexes were characterized by means of NMR spectroscopy. Due to the presence of dppm and dppa with short backbones as bridging ligands, two platinum centres are located in front of each other in these complexes so a Pt…Pt interaction is established. Because of this Pt…Pt interaction, the complexes have bright orange colour under ambient light and are able to strongly emit red light under UV light exposure. These strong red emissions originate from a 3 MMLCT (metal-metal-to-ligand charge transfer) electronic transition. In most of these complexes, the emissions have unstructured bell-shaped bands, confirming the presence of large amount of 3 MMLCT character in the emissive state. Only the complexes bearing dfppy and dppa ligands reveal dual luminescence: a high-energy structured emission originating from 3 ILCT/ 3 MLCT (intra-ligand charge transfer/metal-to-ligand charge transfer) and an unstructured low-energy band associated with 3 MMLCT. In order to describe the nature of the electronic transitions, density functional theory calculations were performed for all the complexes. /journal/aoc 1 of 11 3 J PtH = 41.6 Hz, 2 J PH = 10.6 Hz, 2H, CH 2 of dppm), 6.28 (t, 3 J HH = 6.7 Hz, 2H, H 5 ), 6.38 (m, 3 J FH = 10.6 Hz, 4 J HH = 1.5 Hz, 2H, H 3' ), 6.67 (m, 3 J PtH = 62.4 Hz, 2H, H 5' ), 7. 28-7.34 (m, 12 H, H m and H p of dppm), 7.43 (t, 3 J HH = 7.9 Hz, 2H, H 4 ), 7.68 (d, 3 J PtH = 19.3 Hz, 3 J HH = 5.8 Hz, 2H, H 6 ), 7.73 (d, 3 J HH = 7.9 Hz, 2H, H 3 ), 7.78-7.81 (m, 8H, H o of dppm); δ ( 19 F{ 1 H}) −110.1 (m, 4 J PtF = 78 Hz, 2F, F 2' ), −110.5 (m, 4 J PtF = 51 Hz, 2F, F 4' ); δ ( 31 P{ 1 H}) 22.9 (m, 1 J PtP = 2202 Hz, 3 J PtP = 34 Hz, 2 J PP = 54 Hz, 2P, dppm).

Background The extent to which patients with End-stage renal disease (ESRD) are at a higher risk of COVID-19-related death is still unclear. Therefore, the aim of this study was to identify the ESRD patients at increased risk of COVID-19 -related death and its associated factors. Methods This retrospective cohort study was conducted on 74 patients with ESRD and 446 patients without ESRD hospitalized for COVID-19 in Alborz province, Iran, from Feb 20 2020 to Apr 26 2020. Data on demographic factors, medical history, Covid-19- related symptoms, and blood tests were obtained from the medical records of patients with confirmed COVID-19. We fitted univariable and multivariable Cox regression models to assess the association of underlying condition ESRD with the COVID-19 in-hospital mortality. Results were presented as crude and adjusted Hazard Ratios (HRs) and 95% confidence intervals (CIs). In the ESRD subgroup, demographic factors, medical history, symptoms, and blood parameters on the admission of survivors were compared with non-survivors to identify factors that might predict a high risk of mortality. Results COVID-19 patients with ESRD had in-hospital mortality of 37.8% compared to 11.9% for those without ESRD (P value < 0.001). After adjusting for confounding factors, age, sex, and comorbidities, ESRD patients were more likely to experience in-hospital mortality compared to non-ESRD patients (Adjusted HR (95% CI): 2.59 (1.55–4.32)). The Log-rank test revealed that there was a significant difference between the ESRD and non-ESRD groups in terms of the survival distribution (χ2 (1) = 21.18, P-value < 0.001). In the ESRD subgroup, compared to survivors, non-survivors were older, and more likely to present with lack of consciousness or O2 saturation less than 93%; they also had lower lymphocyte but higher neutrophil counts and AST concentration at the presentation (all p –values < 0.05). Conclusions Our findings suggested that the presence of ESRD would be regarded as an important risk factor for mortality in COVID-19 patients, especially in those who are older than age 65 years and presented with a lack of consciousness or O2 saturation less than 93%.

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