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The uncertainties of distribution generations (DGs) and loads lead to severe voltage fluctuations in active distribution networks (ADNs). Meanwhile, energy storage systems (ESSs) and static var compensators (SVCs) can mitigate the uncertainties of power injections by regulating the active and reactive power. Considering the variations of multiple uncertain factors, this paper proposes a complex affine arithmetic (CAA) based uncertain sensitivity analysis method of voltage fluctuations in ADNs. First, affine models of active and reactive power injections are established. The correlations of noisy symbols are used to reflect the mitigation effects of ESSs and SVCs on the uncertainties introduced by DGs and loads. Next, sensitivity indicators of voltage fluctuations are defined based on the transitivity of noisy symbols. Then, a calculation method for sensitivity indicators based on the micro-increments of coefficients is proposed. Combined with the obtained indicators, a fast sensitivity method for calculating interval values of voltages is further proposed. The modified IEEE 33-bus system is tested to validate the accuracy and efficiency of the proposed method by comparison with the continuous utilization of power flow method. Moreover, the 292-bus system is tested to validate its applicability in a large distribution system. Facts have proved that this method improves the efficiency and reliability of calculations, and in different scenarios, it can achieve fast calculation of nodes and online analysis of the voltage fluctuation range in uncertain environments, provides an effective tool for voltage quality management in active distribution networks.

We conducted this study to investigate the radioprotective effects of recombinant human thrombopoietin (rhTPO) on beagle dogs irradiated with 3.0 Gy 60Co gamma rays. Fifteen healthy adult beagles were randomly assigned to a control group with alleviating care, and 5 and 10 µg/kg rhTPO treatment group. All animals received total-body irradiation using 60Co c-ray source at a dose of 3.0 Gy (dose rate was 69.1 cGy/min). The treatment group received intramuscular injection of rhTPO 5 and 10 µg/kg at 2 h postirradiation, and the control group was administrated the same volume of normal saline. The survival rate, clinical signs, peripheral hemogram, serum biochemistry, and histopathological examination of animals in each group were assessed. Single administration of 10 µg/kg rhTPO at 2 h postirradiation promoted the recovery of multilineage hematopoiesis and improved the survival rate of beagles irradiated with 3 Gy 60Co c rays. The administration of 10 µg/kg rhTPO alleviated fever and bleeding, reduced the requirement for supportive care, and may have mitigated multiple organ damage. [ABSTRACT FROM AUTHOR]

The operational stability is a current bottleneck facing the quantum dot light-emitting diodes (QLEDs). In particular, the device working around turn-on voltage suffers from unbalanced charge injection and heavy power loss. Here, we investigate the operational stability of red emissive CdSe QLEDs operated at different applied voltages. Compared to the rising luminance at higher voltages, the device luminance quickly decreases when loaded around the turn-on voltage, but recovers after unloading or slight heat treatment, which is termed fatigue effects of operational QLED. The electroluminescence and photoluminescence spectra before and after a period of operation at low voltages show that the abrupt decrease in device luminance derives from the reduction of quantum yield in quantum dots. Combined with transient photoluminescence and electroluminescence measurements, as well as equivalent circuit model analysis, the electron accumulation in quantum dots mainly accounts for the observed fatigue effects of a QLED during the operation around turn-on voltage. The underlying mechanisms at the low-voltage working regime will be very helpful for the industrialization of QLED. [ABSTRACT FROM AUTHOR]

Currently, the performance of quantum‐dot light‐emitting diodes (QLEDs) based on environmental‐friendly Cu─In─Zn─S quantum dots (QDs) still lags far behind that of Cd‐QDs‐based devices. Here it is demonstrated that the unique trap‐related recombination in Cu─In─Zn─S QDs is mainly responsible for the low device efficiency. The luminous efficiency of Cu─In─Zn─S‐based QLEDs is rather sensitive to the temperature and hole‐transporting layers (HTLs) due to the susceptible thermal‐related trappingdetrapping processes of holes in radiative Cu‐related traps. The holes in Cu‐related traps can be quenched by escaping to the valence band of the QDs or/and transferring to the adjacent HTLs. An HTL with low highest occupied molecular orbitals is desired to enhance the hole injection and hinder the aforementioned hole transfer. As a result, a high device efficiency of 6.0 cd A−1 is achieved at room temperature, which is attributed to suppressed HTL‐induced emission quenching and efficient valence‐band‐dominated hole injection from HTL to the QDs. The device efficiency is further increased to 13.2 cd A−1 at 150K by suppressing thermal‐induced quenching. [ABSTRACT FROM AUTHOR]

AgIn5S8/ZnS (AIS/ZS) core/shell quantum dots (QDs) have been synthesized using a hot injection method at relatively low temperature without any protection using inert gas. The QDs were characterized with UV visible electronic absorption spectroscopy, PL spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, transmission electron microscopy (TEM), and temperature-dependent time-resolved PL (TRPL). The average size of the QDs was determined to be 1.73 ± 0.29 nm. The QDs exhibit a major excitonic absorption band peaked at 479–573 nm and emission bands peaked from 548 to 666 nm with excitation at 410 nm with the peak position dependent on the synthesis temperature that affects the QD size. Upon the addition of trioctylphosphine (TOP) as a ligand, the PL quantum yield (PLQY) increased to 74.1% compared to 56.7% without TOP. The QDs show high stability after hours of ultraviolet (UV) light exposure or repetitive treatment with a significant amount of polar solvents, which is attributed to surface passivation by the ligands and ZnS shell. The luminescence mechanism of the core/shell AIS/ZS QDs is ascribed to donor–acceptor pair (DAP) recombination. TRPL results suggest that the binding energy of DAP increases and the DAP recombination probability is enhanced after passivation with TOP, leading to the high PLQY. Furthermore, prototype highly pure white light-emitting diodes (LEDs) based on these AIS/ZS QDs have been successfully demonstrated, yielding ideal 1931 CIE coordinates of (0.327, 0.335). [ABSTRACT FROM AUTHOR]