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A new method is developed to prepare RuO2 films through UVO treatment of solution-processed ruthenium(iii) acetylacetonate (Ru(acac)3) without thermal annealing. By introducing RuO2 as an anode buffer layer, highly efficient polymer solar cells (PSCs) have been achieved. The resultant RuO2 layer exhibits high light transmittance in the visible range. Remarkable improvements in the short-circuit current density (Jsc) of the PSCs can be achieved upon the introduction of the RuO2 buffer layer. The PSCs with the RuO2 anode buffer layer demonstrate improved photovoltaic performance in comparison with the devices using poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) as the anode buffer layer. The power conversion efficiency (PCE) of the PSCs based on P3HT:PCBM and P3HT:ICBA reaches as high as 4.19% and 7.07%, respectively. An even higher PCE of 7.45% is realized by adopting a new conjugated polymer, PBDTBDD, as the donor. The results demonstrate that RuO2 has great potential as a hole collection material for highly efficient PSCs. [ABSTRACT FROM AUTHOR]

High efficiency polymer solar cells using solution processed s‐ReOx as the anode buffer layer are demonstrated. The s‐ReOx layer can effectively change the light distribution within the photoactive layer and enhance its absorption. The solution‐processable s‐ReOx is a promising anode buffer layer material for high performance PSCs [ABSTRACT FROM AUTHOR]

We report polymer solar cells (PSCs) based on poly(3-hexylthiophene (P3HT) and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) using water-soluble nickel acetate (Ni(CH3COO)2, NiAc) instead of acidic poly(3,4-ethylenedioxythiophene) : poly(styrenesulfonate) (PEDOT : PSS) as hole collection layer (HCL) between the indium tin oxide (ITO) electrode and photoactive layer. The NiAc layer can effectively decrease Rs and increase Rp and shows effective hole collection property. Under the illumination of AM1.5G, 100 mW/cm2, the short-circuit current density ( Jsc) of the NiAc based device (ITO/NiAc/P3HT : PCBM/Ca/Al) reach 11.36 mA/cm2, which is increased by 11% in comparison with that (10.19 mA/cm2) of PEDOT : PSS based device (ITO/PEDOT : PSS/P3HT : PCBM/Ca/Al). The power conversion efficiency of the NiAc based devices reach 3.76%, which is comparable to that (3.77%) of the device with PEDOT : PSS HCL under the same experimental conditions. Moreover, NiAc based PSCs show superior long-term stability than PEDOT : PSS based PSCs. Our work gives a new option for HCL selection in designing more stable PSCs. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

Abstract: We demonstrate efficient polymer solar cells (PSCs) based on poly(3-hexylthiophene) (P3HT) and fullerene derivatives ether Indene-C60 Bisadduct (IC60BA) or Indene-C70 Bisadduct (IC70BA)) by using solution-processed titanium(IV) oxide bis(2,4-pentanedionate) (TOPD) as electron collection layer (ECL) between the Al cathode and photoactive layer. The TOPD buffer layer was simply prepared by spin-coating isopropanol solution of TOPD on active layer and then baked at 80°C for 15min. The short-circuit current density (Jsc ) and the open-circuit voltage (Voc ) of the devices can be simultaneously and significantly improved by optimizing the electron collection layer, the photoactive layer and the device fabrication conditions. The power conversion efficiency (PCE) of the P3HT:IC60BA BHJ device with TOPD buffer layer reaches 5.0% under the illumination of AM1.5G, 100mW/cm2, which is increased by 27% in comparison with that (3.9%) of the device without TOPD buffer layer under the same experimental conditions. When IC70BA was chosen instead of IC60BA, the BHJ device could show better performance with PCE of 5.59%. The results indicate that TOPD is a promising electron collection layer for PSCs. [Copyright &y& Elsevier]

Abstract: We demonstrate efficient inverted polymer solar cells (PSCs) based on poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) by using solution-processed titanium(IV) oxide bis(2,4-pentanedionate) (TOPD) as electron collection layer (ECL) between the indium tin oxide (ITO) electrode and photoactive layer. The TOPD buffer layer was prepared by spin-coating isopropanol solution of TOPD on ITO and then baked at 140°C for 5min. The power conversion efficiency (PCE) of the inverted PSC with TOPD buffer layer reaches 4% under the illumination of AM1.5G, 100mW/cm2, which is increased by 76% in comparison with that (2.27%) of the inverted device without TOPD ECL. The results indicate that TOPD is a promising electron collection layer for inverted PSCs. [Copyright &y& Elsevier]

Mesoporous TiO with anatase crystalline structure (MTiO/F) has been synthesized by using vinylidene fluoride/chlorotrifluoroethylene copolymer (1:9 in mole, F) as template. The synthesized mesoporous titania samples were characterized by a combination of various physicochemical techniques, such as X-ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, and N adsorption/desorption. It was found that without any external doping, MTiO/F exhibited significantly higher photocatalytic activities for the degradation of rhodamine B (RhB) dye than P25 TiO under visible light irradiation. Furthermore, the UV-Vis absorption maximum of the dye solution exhibited a gradual hypsochromic shift due to de-ethylation and degradation of RhB dye. [ABSTRACT FROM AUTHOR]

In supercharged GDI engine, due to the low efficiency of oil-air separator, oil droplets enter combustion chamber and form local hot spots leading to 'super knock', and using CFD simulation in analyzing the efficiency of oil-air separator has the drawbacks of convergence difficulty and high demands on computing resources. In view of that, an alternative two-phase flow calculation scheme--Euler-Lagrangian algorithm is presented in this paper. The specific ideas of the algorithm is that firstly Euler algorithm is used to calculate the gaseous-phase flow field of oil-air separator, then based on the calculation results oil particles are introduced and using Lagrangian particle tracking algorithm to analyze liquid-phase flow field and find out the rule of particle movement in flow field and indirectly evaluate the separation efficiency of oil-air separator. Finally the best structure of oil-air separator is sorted out through schemes comparison. [ABSTRACT FROM AUTHOR]

Abstract: A new series of four fluorene-thiophene copolymers, PF-co-2%TAQI, PF-co-5%TAQI, PF-co-10%TAQI and PF-co-15%TAQI, were synthesized by the Suzuki cross-coupling polymerization of 9,9-dihexylfluorene-2,7-dibromofluorene and N-butyl 6-[3-(2,5-dibromothienyl)]anthraquinone-2,3-dicarboxylic imide. The polymers have good solubility in common organic solvents and can form thin films by spin coating or casting. The UV–vis and photoluminescence (PL) spectra for the copolymers in dilute solution are similar to those of polyfluorene, i.e. maximum absorption at 381nm and 417nm and PL at 439nm. The UV–vis spectra of the polymer films also exhibit a single peak at 378nm, while an extra emission peak was found at 612nm, 618nm, 628nm and 626nm for PF-co-2%TAQI, PF-co-5%TAQI, PF-co-10%TAQI and PF-co-15%TAQI, respectively, presumably resulting from the excimer of anthraquinone imide groups. The electroluminescent properties of the copolymers were investigated using single-layer (ITO/PEDOT/Polymer/LiF/Al) and double-layer (ITO/PEDOT/Polymer/TPBi/LiF/Al) (TPBi, 1,3,5-Tris(1-phenyl-1H-benzimidazol-2-yl)benzene) LED devices. The double-layer devices based on copolymers emit multicolors under different voltages. The Commission Internationale de l’Eclairage (CIE) coordinates of PF-co-2%TAQI are (0.356, 0.249), (0.285, 0.210), (0.264, 0.277) and (0.240, 0.250) under 12V, 14V, 16V and 18V, respectively. [Copyright &y& Elsevier]

A large number of drainage pipes and canals in China have been in disrepair for a long time and there have been problems such as leakage and corrosion. In response to these problems, this paper studies a non-excavation technology for repairing the arched canal structure—the in-situ spraying method. To study the influence of the original canal structure on the mechanical characteristics of the lining structure by in-situ spraying and the restraint effect on the lining structure, a field model test with a similar ratio of 1:2 was conducted in the field test pit. By conducting four stages of three-point concentrated load loading tests, the mechanical characteristics of the lining structure were investigated to reveal the influence of the canal structure on the force of the lining structure. The test results show that: the maximum crack width of the newly added lining structure is 0.27 mm and the normal service ultimate bearing capacity of the arched structure repaired by H-70 reaches 150 kN; comparing the loading test and the numerical simulation results, the difference between the two vault displacement results is 4.65% and the results are relatively consistent. The displacement of the bottom of the lining structure is small and the participation of the bottom plate is small, while the displacement of the upper arch structure of the lining is significantly larger than the lateral displacement, indicating that the canal structure can effectively limit the lateral displacement of the newly added lining and that the canal structure is greatly reduced. The bending moment of the lining structure is improved and the restraint effect on the arch foot is more obvious. This paper proposes the use of H-70 to repair arched canal structures by the in-situ spraying method and seeks to prove the feasibility of this method and fill the gap of research in this area. This paper provides the structural design basis and experimental knowledge for the construction of the repair method, which has important practical significance for the pipeline repair project in the future. [ABSTRACT FROM AUTHOR]

Aim. To explore potential resilience and psychological flexibility patterns in nurses and analyze the effects of related factors such as growth mindset and professional recognition of categories. Background. Resilience and psychological flexibility can help nurses resist occupational pressure and play essential roles in promoting personal growth and professional development. Methods. A latent category approach was used to examine the patterns of heterogeneity in resilience and flexibility among 805 nurses. Differences in the influences related to resilience and flexibility were analyzed using univariate and multivariate logistic regressions, with demographic information, growth mindset, and career recognition as covariates. Results. Participants were divided into three potential categories: toughness-flexible (32.8%), power-deficit-emotional (23.1%), and toughness-rigid (44.1%). The results of multivariate logistic regression analysis showed that monthly income, mode of employment, growth mindset, and professional identity were influential factors in the potential categories of nurse resilience and flexibility. Conclusion. One cohort of nurses had high resilience and low flexibility, and psychological rigidity was related to the fact that the monthly income was less than RMB 5,000 and the contractual mode of employment. An excellent growth mindset and a high professional identity indicate that nurses are resilient and flexible. Implications for Nursing Management. Hospitals and nursing managers should pay attention to nurses' different career development needs and implement appropriate safeguards. [ABSTRACT FROM AUTHOR]

Unbalanced photocurrent output for each sub-cell in monolithic multiple junction solar cells (MMJ-SCs) reduces the achievable photovoltaic power efficiency (PCE). Here, we first introduce Au decahedra nanoparticles to realize the plasmon-enhanced photo-absorption of GaInP top-cell and achieve the current-matched MMJ-SCs. By simply spin-coating the Au decahedral nanoparticles on the illuminated surface of the devices, the PCEs of the monolithic double junction and triple junction solar cells increase significantly from 27.01% to 28.63% and from 29.88% to 31.90%, respectively. Both the theoretical local electromagnetic distributions and the experimental extinction properties confirm the plasmonic induced absorption enhancement in device performance, and further elucidate the essential reason for photocurrent enhancement derives from the more furious oscillation of free electrons in the vicinity of sharp vertexes for Au decahedra nanoparticles. Our results demonstrate that Au decahedra with sharp vertexes and edges are promising for meliorating the trade-off between light absorption and carrier collection in GaInP top-cell. In addition, this facile and simple strategy also highlights non-annealing treatment and prevents the impurity diffusion at high temperature for MMJ-SCs, and may facilitate other types of solar-harvesting devices. [ABSTRACT FROM AUTHOR]

All‐inorganic CsPbI2Br perovskite has attracted great attention due to the stable crystal structure and moisture resistance, and its 1.91 eV bandgap is close to the optimal bandgap of indoor artificial light sources, making it be the best candidate for the indoor photovoltaics (IPVs) to power a wide range of internet of things related electronic devices. Herein, we report on the preparation of CsPbI2Br with α‐phase and the improvement of its phase stability by adding lead acetate in the CsPbI2Br precursor. A series of dopant‐free conjugated polymers (P3HT, PBDB‐T, and PM6) with different highest occupied molecular orbital energy levels are introduced as hole transport layers for building IPV devices. The PM6 based devices having better energy alignment with perovskite demonstrate best indoor photovoltaic performance, giving a remarkable open‐circuit voltage of 1.15 V and high fill factor of 81.86% under 1000 lux (330 µW cm−2) light‐emitting diode illumination, and finally realizing a decent power conversion efficiency of 33.68%. Our findings suggest that collaboratively optimize the CsPbI2Br layer and hole transport layer is an effective approach to realize high performance IPVs. [ABSTRACT FROM AUTHOR]

Aim: To explore the experiences of nurses' work stress related to COVID‐19 regular epidemic prevention and control in China. Background: The global COVID‐19 epidemic is still severe, and China's ongoing regular epidemic prevention and control still cannot be relaxed, which places demands on nurses. Methods: Thirty nurses and eight nurse managers were interviewed using semistructured in‐depth interviews, and the data were analysed by the Colaizzi seven‐step analysis method. Results: Four themes were extracted as follows: environmental factors, organizational factors, personal factors and positive factors in coping with stress. Conclusions: Nursing managers should pay attention to construction of the first‐line departments of regular epidemic prevention and control. The shortage of nurses' human resources and the increase of nurse–patient conflicts are problems that need to be solved urgently. In addition, this research also emphasizes the importance of promoting nurses' stress‐related growth and thinking about the possibility of reform. Implications for Nursing Management: The construction of the hospital environment and increasing the resilience of nursing teams require attention. We should attach importance to the training of nurses' communication skills and provide sufficient organizational support and economic guarantees for nurses. Finally, perhaps we should also consider whether it is necessary to reform the relevant hospital systems and how to reform them. [ABSTRACT FROM AUTHOR]

• Theoretical analysis indicates lower binding energy (E b) can reduce the V oc loss. • A theoretical PCE of 18.86% was obtained via optimizing the E b values. • PM6:Y6 film with a 0.14 eV E b was achieved via optimizing the CN concentration. • PM6:Y6-based devices with a 0.14 eV E b reach a PCE of 16.14%. • Short electron-hole pair binding distances (a) can further reduce V oc losses. The energy loss during exciton dissociation is one of key reasons for organic solar cells (OSCs) with inferior performance. Herein, a theoretical and experimental guidance for highly efficient OSCs with outstanding exciton dissociation rate is introduced via fine-tuning the binding energy (E b) and the electron-hole pair binding distance (a) in the charge transfer (CT) state. Results suggest that decreasing the E b appropriately is favorable for higher photovoltaic conversion efficiency (PCE). Hence, we attempt to modulate the E b of PM6:Y6 photoactive layer by changing additive and their corresponding concentration. Investigations show that the E b of PM6:Y6 changes slightly with different additives, and the chloronaphthalene (CN) with appropriate concentration affords an E b of 0.14 eV, and thus supporting the excellent efficiency of 16.14%. Meanwhile, the influences of the internal spacing of electron and hole in CT state on device performance were explored for further elucidating carrier micro-transport mechanism and instructing further experimental investigation. [ABSTRACT FROM AUTHOR]

Abstract: For highly luminescent solid-state applications, the twisted or spiro-configured conjugated molecules are mostly considered as the proper choices because the coplanar ones usually have intensively intermolecular π–π interactions, which lead to fluorescence quenching and red-shift. In this study, the two prepared parallel H-shaped phenylenevinylenes with coplanar configuration show the special case. Due to their characteristics of multi-branches, these coplanar multi-branched molecules prefer to form stable amorphous morphology in thin films were verified by the XRDs and AFM. The amorphous thin films show very weak intermolecular actions, with intrinsic differences on both steady and transient optical properties from the crystalline states. The non-doped electroluminescent devices based on them show highly luminescent blue emissions. Both their luminance (20490cdm−2) and efficiency (2.8cdA−1/2.6lmW−1) are comparable with the performances of the cross dimeric OPVs which have similar constructing blocks to the H-shaped molecules and with the same EL device configurations. [Copyright &y& Elsevier]