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In this study. a novel near-infrared fluorescent-driven contrast agent (Ag-doped NaYF4:Yb3+/Er3+@NaYF4:Nd3+@NaGdF4) was synthesized using a coprecipitation-hydrothermal-solvothermal-solvothermal (CHSS) method. The results shows that hexagonal NaYF4:Yb3+/Er3+ with a diameter of 300 nm was successfully synthesized by the CHSS method. The new contrast agent was characterized using scanning electron microscopy, fluorescence spectrometry, transmission electron microscopy, energy-dispersive spectrometry and ultraviolet-visible light diffuse reflectance absorption spectroscopy. Even at low concentrations (0.2 M), this proposed contrast agent can be excited by near-infrared light with a wavelength of 980 nm and emits a dazzling green light with a wavelength of 540 nm, and the comparison of the luminescence intensity proves that doping with silver increases the luminescence intensity of the upconverted nanomaterial by nearly 13 times based on the calculated quantum yield. TEM images show the successful preparation of silver nanoparticles with a diameter of 30 nm, and the energy spectrum shows the successful doping of silver nanoparticles and the successful preparation of the core-shell structure of NaYF4:Yb3+/Er3+@NaYF4:Nd3+@NaGdF4. Furthermore, the mechanism of the increased luminous intensity has been studied using simulation calculations. Finally, cytotoxicity tests were used to test material which was modified by 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[amino(polyethylene glycol)-2000] (DSPE-PEG2K), and the biocompatibility was significantly improved, meeting the standard for biological applications. [ABSTRACT FROM AUTHOR]

Two key concerns exist in contemporary cancer chemotherapy: limited therapeutic efficiency and substantial side effects in patients. In recent years, researchers have been investigating the revolutionary cancer treatment techniques of photodynamic therapy (PDT) and photothermal therapy (PTT) proposed by many scholars. A photothermal treatment of cancer was synthesized using the hydrothermal method which has high photothermal conversion efficiency and can generate reactive oxygen species (ROS) in cells. Photothermal treatment of tumors has a good short-term effect and photodynamic therapy lasts longer. However, both PTT and PDT have their inevitable shortcomings and it is difficult to completely eradicate a tumor using a single mode of treatment. PTT and PDT synergistic treatment not only inherits the advantages of low toxicity and side effects of phototherapy but also enables the two treatment methods to complement each other. It is an effective strategy to improve curative effects and reduce toxic and side effects. Furthermore, gold doped UCNPs have an exceptionally high target recognition for tumor cells. The gold doped UCNPs, in particular, are non-toxic to normal tissues, endowing the as-prepared medications with outstanding therapeutic efficacy and exceptionally low side effects. These findings may encourage the creation of fresh, effective imaging-guided approaches to meet the goal of photothermal cancer therapy. [ABSTRACT FROM AUTHOR]

In this paper, fast trap behaviors in Ge pMOSFETs with Al2O3/GeOx/Ge gate-stack are evaluated and quantitatively characterized using a novel sub-1-ns ultrafast measurement (UFM) system. By changing the operation temperature and the rising time of the applied gate voltage (${V}_{\text {g}}$), it is found that the fast trap filling process could be observed within the first 10 ns after the gate voltage was applied, and the process would be more clearly characterized at a raised operation temperature. In addition, the trap density distribution and the time constant of the fast traps inside the valence band edge are experimentally extracted based on the UFMs. It is found that the trap densities inside the valence band edge are within the range of 1013 to 1014 cm $^{-2}\cdot \text {eV}^{-1}$ , which are consistent with the reported values from the Hall measurements. It is experimentally confirmed that the time constants of the fast traps in Ge pMOSFETs with Al2O3/GeOx/Ge gate-stack are about 10 ns, and deeper energy level corresponds to smaller time constant. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) are one of the most promising lab-scale technologies to deliver inexpensive solar electricity. Low-temperature printable carbon counter electrode based planar-heterojunction PSCs are particularly suitable for future large-scale manufacturing, but suffer from an inferior efficiency. Here, we demonstrate a TiO2/SnO2 bilayer as the electron transport layer (ETL) for carbon counter electrode based planar-heterojunction PSCs together with micromolecule Cu-phthalocyanine (CuPc) as the hole transport layer (HTL), yielding a high power conversion efficiency of 15.39% and an excellent stability over 1200 h. The improved performances are attributed to a better energy level transition, a suppressed electron–hole recombination, and a wider depletion region of the TiO2/SnO2 bilayer. Our work represents a great advancement in the fabrication and popularization of carbon counter electrode based PSCs. More importantly, the whole devices are processed at a temperature below 200 °C, providing potential application of PSCs in monolithic tandem devices and paving the way for the development of carbon based flexible PSCs. [ABSTRACT FROM AUTHOR]

In this letter, a novel fast threshold voltage ( Vth ) measurement (FVM) technique is proposed and demonstrated, which could perform I – V characterization of MOSFETs within 1 ns. With the advanced FVM technique, down to 1-ns negative biased temperature instability (NBTI) characterization was successfully carried out for Si pFinFETs at 14-nm technology node. It is experimentally confirmed that the nano-second-level fast recoverable traps, which are generated during NBTI stress, could lead to the underestimation of Vth degradation under micro-second-level measurement speed. Furthermore, it is found that even when the Vth measurement is performed within 1 ns after the stress removal, it is still not fast enough to be the real recovery-free measurement. Yet, with the proposed FVM technique, NBTI characteristics could be characterized more accurately and closer to its intrinsic behaviors. [ABSTRACT FROM PUBLISHER]

In this paper, we investigate the carrier transport characteristics of the ultrascaled Si FinFETs. Traditional dc characterization technique is compared with the ultrafast pulsed IV method. Due to the severe self-heating effect introduced in the characterization process, the ballistic transport parameters extracted using dc method would show essential discrepancies from those in the real high-speed IC circuits. Therefore, an ultrafast pulsed IV measurement technique is proposed for accurate ballistic transport characterization. Furthermore, since the series resistance ( R{\textbf {SD}} ) of the Si FinFETs is temperature-dependent, a modified backscattering model is adopted to extract the ballistic transport parameters without the influence of the temperature-variant R{\textbf {SD}} . A ballisticity scaling model was established to predict the scalability of the ballistic transport parameters. It is found that very high ballisticity could be achieved for FinFETs with sub-10-nm technology nodes. [ABSTRACT FROM AUTHOR]

Forest landscape multifunctionality (FLM) provides multiple benefits, such as climate regulation, water storage, and biodiversity maintenance. However, the external factors limiting FLM have not been fully identified, although addressing them could contribute to sustainable development. The present study aimed to identify and quantify the role of urbanization as an external factor that affects FLM. To this end, impervious area changes in Liaoyuan, China, were observed from 2000 to 2018, and 10 buffer zones at 500 m intervals were established outside the city. Within each buffer zone, we analyzed changes in forest landscape functions, including habitat maintenance, carbon sequestration, and water yield, as well as changes in the multifunctionality of their composition. The urbanization of Liaoyuan was significant in 2000–2018. The functions of the forest landscape became stronger and more stable as they were located further away from the urban edge. We refer to this pattern as the gradient effect of urbanization. Specifically, urbanization affected the investigated functions at a distance of 1000–2500 m. The FLM showed a more significant gradient effect of urbanization. The impact distance of urbanization on the FLM increased from 3000 m in 2000 to over 5000 m in 2018. This impact distance increased significantly whenever urbanization strengthened significantly (i.e., in 2005–2010 and 2015–2018). These findings are instructive for forest and urban managers working to achieve multiple Sustainable Development Goals. [ABSTRACT FROM AUTHOR]

Power packs integrating both photovoltaic parts and energy storage parts have gained great scientific and technological attention due to the increasing demand for green energy and the tendency for miniaturization and multifunctionalization in electronics industry. In this study, we demonstrate novel integration of perovskite solar cell and solid-state supercapacitor for power packs. The perovskite solar cell is integrated with the supercapacitor based on common carbon electrodes to hybridize photoelectric conversion and energy storage. The power pack achieves a voltage of 0.84 V when the supercapacitor is charged by the perovskite solar cell under the AM 1.5G white light illumination with a 0.071 cm 2 active area, reaching an energy storage proportion of 76% and an overall conversion efficiency of 5.26%. When the supercapacitor is precharged at 1.0 V, an instant overall output efficiency of 22.9% can be achieved if the perovskite solar cell and supercapacitor are connected in series, exhibiting great potential in the applications of solar energy storage and flexible electronics such as portable and wearable devices.