Top-down Composition Research Articles

A large-capacity, superhigh-rate integrated lithium metal anode with top-down composition gradient enabled by polyantimonic acid

Lattice-water-containing polyantimonic acid is found to favor the construction of a large-capacity and superhigh-rate integrated Li-metal anode with unique top-down composition gradient of Li2O–LiOH–Li3Sb/Li via spontaneous phase separation process.

On the tip of the pen: Effects of character-level lexical variables and handwriter-level individual differences on orthographic retrieval difficulties in Chinese handwriting.

In the past few decades, Chinese speakers have suffered from difficulties in handwriting, which include tip-of-the-pen (TOP) states (knowing a character but failing to fully handwrite it) and character amnesia in general (a general inability to handwrite a character despite being able to recognise it). The current study presents a systematic empirical investigation of the effects of character-level lexical characteristics and handwriter-level individual differences on TOP, character amnesia, and partial orthographic access in TOP states. Using a spelling-to-dictation task, we had 64 participants to handwrite 200 simplified Chinese characters. We showed that, at the lexical level, participants experienced more TOP and character amnesia in handwriting if a character was less frequent, was acquired later in life, was embedded in a less familiar word, or had more strokes; TOP but not character amnesia was additionally affected by phonetic radical order and spelling regularity. At the handwriter level, people also experienced more TOP and character amnesia if they had more digital exposure, less pen exposure, or less print exposure. In a TOP state, partial orthographic access was more likely if a character was acquired later in life, had fewer strokes, or had a left-right or top-down composition or, if a handwriter had less digital exposure.

Low-dose X-ray-stimulated LaGaO3:Sb,Cr near-infrared persistent luminescence nanoparticles for deep-tissue and renewable in vivo bioimaging

X-ray-stimulated near-infrared persistent luminescence nanoparticles (NIR-PLNPs) offer attractive capabilities for autofluorescence free deep-seated imaging and depth-independent treatment, but still suffer from adverse effects caused by high-dose X-ray irradiation (>5 Gy). From the viewpoint of two centers of NIR-PLNPs, i.e., X-ray photon absorption center and defects center, we here propose a top-down composition design strategy for the development of low dose X-ray-stimulated NIR-PLNPs with improved X-ray photon absorption efficiency and optimized persistent luminescence (PersL) performance. Successfully, hypersensitive X-ray-stimulated NIR-PLNPs LaGaO3:Sb3+,Cr3+ with a super-long PersL emission (>500 h) at ∼750 nm are prepared. The nature of high Z atomic constituents of the host LaGaO3 endows these NIR-PLNPs with strong X-ray absorption capacity. Simply by codoping with size-mismatched ions Sb3+, the concentration of oxygen vacancies in the host is rationally optimized, leading to the enhanced NIR PersL performance of Cr3+ ions. In vivo bioimaging demonstrates that the designed X-ray-stimulated NIR-PLNPs LaGaO3:Sb3+,Cr3+ can be readily reactivated under X-ray irradiation with even a lower dose to 0.37 Gy, showing the advantages of these nanoparticles on deep-seated imaging and treatment. More importantly, we anticipate that our proposed top-down composition design strategy can be applied to develop much low dose X-ray-stimulated NIR-PLNPs in the future.

Facile solution-controlled growth of CuInS 2 thin films on FTO and TiO 2/FTO glass substrates for photovoltaic application

This paper reports on the preparation of two thin films (CuInS 2/FTO and CuInS 2/TiO 2/FTO) by a facile solvothermal method and their photovoltaic properties. Instrumental measurements including X-ray diffraction (XRD), inductively coupled plasma emission spectroscopy (ICP), scanning electron microscopy (SEM), and UV–vis spectra have been used to characterize the obtained CuInS 2 thin films. The results show that the CuInS 2 films deposited on fluorine-doped tin oxide-coated (FTO) conductive glass substrates are composed of nanoplates and microspheres. The thickness of the CuInS 2/FTO films can be adjusted from 1 μm to 8 μm by controlling the solution concentration of the reactants. While, the prepared 10 μm-thick CuInS 2 film on the TiO 2 film substrate consists of nanoplates. The UV–vis absorption spectra reveal that the CuInS 2 thin films have a strong absorption around 400–850 nm and the band-gap energy is tunable in the range of 1.45–1.61 eV with the variation of Cu/In ratio from 1.20 to 0.90. Furthermore, two types of thin film solar cells, which have an effective area of 0.25 cm 2 and possess separately the top-down composition of Ag/CdS/CuInS 2/FTO and FTO/TiO 2/CuInS 2/Au, were fabricated after heat-treatment to evaluate their photovoltaic properties and the corresponding conversion efficiency is 0.33% and 0.29% under AM 1.5 irradiation (100 mW cm −2), respectively.

Parametric study on non-vacuum chemical vapor deposition of CuInS 2 from a single-source precursor

Copper indium disulfide (CuInS 2) films were deposited by aerosol-assisted chemical vapor deposition (AACVD) from a single-source precursor (SSP), (PPh 3) 2Cu(SEt) 2In(SEt) 2. Various deposition parameters were explored to understand how they affect the crystallography, stoichiometry, and morphology of the deposited films and the quality of fabricated solar cells. Parameters explored included the deposition temperature, location of substrate within CVD reactor, precursor concentration in toluene carrier solvent, and post-deposition annealing in a S-rich atmosphere. CuInS 2 films have been fabricated into complete solar cells with the top-down composition of Al/ZnO:F/CdS/CuInS 2/Mo/glass and the efficiency of 1.0% under simulated AM0 illumination.

Structured extension of COBOL for handling data bases

The most important aspects of a modest data base management system are described on the basis of our experiences in implementing it. Data structuring facilities of the system include two basic data structures: lists and binary search trees; and a simple rule of their top-down composition. The class of structures that may be obtained this way is rather restricted in comparison with the CODASYL proposal, but still fairly powerfull and permits definition and easy implementation of an elegant data manipulation language (DML). Operations of the DML have simple syntax and semantics and allow implementation in which the structure of the data base is protected against illegal actions on the part of the programmer. Since implementation of the system requires some modest effort, we offer it as an experiment which shows how existing software facilities can be extended in simple and still essential ways, for applications where all the generality of general data base management systems is not really necessary. Design of the system was motivated by the work of Schneidermann and Scheuerman on structured data structures and it contains several important clarifications and improvements of their suggestions, together with implementation aspects.