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A free-standing palladium/reduced graphene oxide paper (Pd/rGOP) based on one-pot co-reduction was prepared. The as-prepared Pd/rGOPs contain evenly distributed Pd particles interposing between the rGOP layers. The structure and composition of Pd/rGOP were characterized by SEM, EDX, XRD and Raman spectra. We investigated the glucose sensing performance of Pd/rGOP by chronoamperometry, the sensitivity reach as high as 6.70 µA mM−1 cm−2 with the linear range between 0.5 mM and 8 mM. The sensor also exhibits a good anti-interference ability and detection selectivity toward the interference. The proposed sensor has great potential to become a reliable tool in point-of-care medical devices.

Paper-based supercapacitors have attracted more and more attention for high electrochemical performance. However, most of them adopt sandwiched structure. Here, we prepared planar polypyrrole (PPy) coated paper-based supercapacitors by applying simple laser carving assisted method. The planar device showed a significant performance improvement (13.9 mF/cm2) compared to the sandwiched device (12.3 mF/cm2). In addition, by adjusting the polymerization time of pyrrole, the device capacity can be further increased to 87.4 mF/cm2. We firmly believed that the laser carving assisted method has a significant role in promoting the development of flexible planar electronic devices.

Effect of ferric chloride concentration on micro-nano structure surface and superhydrophobic property of filter paper was investigated by adsorption and simple immersion process. The results showed that the concentration of ferric chloride solution had great impact on the superhydrophobic property of filter paper. When the concentration was 0 mol/L, filter paper presented hydrophilicity. When the concentration was bigger than 0 mol/L, it exhibited hydrophobicity. The modified filter paper’s surface displayed advancing contact angels of 167 ± 2°, which was attributed to its’ formed micro/nano structure. This may contribute to the development in production applications.

Polyaniline (PANi) is synthesized on a highly ordered and flexible graphene paper (GNP) by in situ polymerization followed by folding the 2D composite paper into a 3D structure. The thermoelectric properties of this novel composite structure is improved as a result of the formation of an electrically connected, thermally disconnected structure due to the interconnected folds within the composite that allow electrons to conduct while discouraging phonon transport. Mechanical compaction on the folded sample is essential to produce a consolidated sample. ZT of this novel composite is an order of magnitude higher than that of neat GNP paper.

The report entitled "L. Liu, D. Li, F. Bai, A relative Lempel-Ziv complexity: Application to comparing biological sequences, Chem. Phys. Lett. 530 (2012) 107-112" mentions on the powerful construction of phylogenetic trees based on Lempel-Ziv algorithm. On the other hand, the method explained in the paper does not give promising result on the data set on invasive Caulerpa taxifolia in the Mediterranean Sea. The phylogenetic trees are obtained by the proposed method of the aforementioned paper in this short note. (C) 2018 Elsevier B.V. All rights reserved.

Reduced graphene oxide (RGO) papers are extensively applied in gas sensors, electronic devices, and electromagnetic shielding. However, the structures and electrical properties for RGO papers are hard to precisely fabricate and evaluate. We developed an effective method to prepare the multi-layer RGO papers by interfacial self-assembly and natural sedimentation. The thermal structural evolutions have been elaborately measured by thermogravimetric and differential scanning calorimetry (TG-DSC) analysis, X-ray diffraction (XRD) and FT-IR spectra. Consequently, the electric properties, such as conductivity, dielectric constants, and impedance, were investigated by direct LCR measurement. We think these RGO papers would be very valuable in electromagnetic interference (EMI) shielding, heat-protective materials, and flexible electrodes.

We report on the development of highly attractive nanostructured samples derived from three-dimensional microfibrous carbon paper (MFCP) uniformly decorated with multi-walled carbon nanotubes (MWNTs). We were able to show that a standard electrochemical oxidation of these 3D-nanostructures, in nitric acid solution, leads to: (i) a remarkable increase of their specific surface area reaching 208 m 2 /g as compared to 71 m 2 /g for the untreated samples, (ii) a reversal in their wettability behavior (from hydrophobic to hydrophilic), and (iii) a significant enhancement of their electrochemical activity. The MWNTs-coated MFCP material is highly promising for supercapacitor applications as it exhibits high capacitance of 165 F/g.

Two successive generations of multiwalled carbon nanotubes (MWCNT/1 and MWCNT/2) have been produced by a unique CVD procedure using fibers of a commercial carbon paper as support. MWCNTs/1 have diameters comprised between 30 and 50 nm and are about 10 μm long. They are firmly attached to the carbon paper support. MWCNTs/2 have diameters of 10–20 nm and lengths of several 100 nm. They are grown on MWCNTs/1 and have a density of about 40 nanotubes per micrometer length of MWCNTs/1. This hierarchical nanostructure may find application as support for electrochemical catalysts, especially those used in fuel cells.

A large density of multiwall carbon nanotubes (MWCNTs) has been grown on the fibers of a carbon paper using a sulfonated silane intermediary to uniformly disperse (1:1) Ni–Co catalytic sites used in the decomposition of ethylene. The nanotubes were obtained at 800 °C by Ohmically heating the carbon paper support. The MWCNTs are typically up to 20 μm in length and between 30 and 50 nm in diameter. These tubes are easily opened at room temperature, while remaining firmly attached to the carbon paper.

Multi-walled carbon nanotubes (MWCNTs) have been grown from ethylene on the fibers of carbon paper by Ohmically heating Co–Ni or Fe catalytic sites supported on the carbon fibers. MWCNTs are mainly tip-grown and have diameters ranging from 10 to 30 nm, depending on the catalyst used. The MWCNTs adhere firmly to the carbon paper with which they are in electrical contact. Cyclic voltammetry of the electrode thus formed indicates that MWCNTs behave like a graphitic material.

In order to achieve light and flexible gas sensor, we fabricated a uniform carbon nanotube paper made by multi-walled carbon nanotube and employed it as a sensing part. Referring to the transient behavior, it was clarified that the sensor response followed Langmuir isotherm, similar to the previous results prepared on a glass substrate. A repetition characteristics was quite stable and sensitivity was higher than previous one. Thus, it opens prospects for application, but it is unclear why the sensitivity is high despite the increased thickness.

NMR correlation maps of paper samples suggest a two-site residence model for water in the ultrastructure of cellulose. When cross-linking and degradation of cellulose occur due to γ-irradiation-induced ageing, a significant fraction of water appears confined into low-mobility sites of the cellulose matrix. As the cellulose damage grows more pronounced, the two-site structure turns into a single-site water arrangement.

The electrospinning process has been used successfully to fabricate the multiwalled carbon nanotubes (MWCNTs)-embedded polyacrylonitrile (PAN) nanofiber paper. The diameters of nanofibers decreased with increasing CNT concentration. We found large anisotropic electrical conductivity, i.e., the electrical conductivity of the carbonized nanofiber paper along the spinning direction was about three times larger than that normal to the spinning direction, in good contrast with observations that the carbonized PAN nanofiber paper without CNTs did not reveal anisotropy in electrical conductivity. This proves that CNTs in PAN nanofiber were preferentially aligned along the nanofiber axis, in excellent agreements with transmission electron microscopy observations.

We have developed a new method to directly fabricate lithium cobalt oxide (LiCoO 2 ) films onto porous films by an electrodeposition method in solutions at low temperature. A set of porous substrate films consisting of a PTFE membrane-filter and paper was placed between a LiOH solution and a CoSO 4 solution. Cobalt compounds were deposited on the substrates under electrical currents of ∼1 mA/cm 2 using carbon electrodes. As a result, we found that LiCoO 2 films on the porous filter were successfully fabricated at 120 °C. Furthermore, the LiCoO 2 films did not cover the entire substrate, but formed only in the shape of the anode.

The analysis of Mn–chalcogen bond length and of tetrahedral covalent radius of Mn (rtcMn) in AII1−xMnxBVI and in Mn chalcogenides, performed in the previous paper [Chem. Phys. Lett. 350 (2001) 577], was supplemented here by the case of AIII1−xMnxBV (AIII=In, Ga; BV=As, N) compounds. It was found that for chalcogen anions the dependence of rtcMn vs anion atomic number (Aa) can be linearly approximated. Inclusion of the respective rtcMn values for the group-V anions (As, N) reveals their consistency with the above rtcMn(Aa) dependence thus suggesting its more `universal' character.

Article, Chemical Physics Letters. 414(4-6):444-448 (2005)

The analysis of the Mn–chalcogen atom (Te, Se, S) bond lengths in Mn-based AII–BVI and AIV–BVI metal chalcogenides (derived from X-ray absorption fine structure studies) as well as in Mn chalcogenides (from X-ray diffraction (XRD)) enabled the author to introduce certain self-corrections into the papers [Chem. Phys. Lett. 283 (1998) 313; Chem. Phys. Lett. 336 (2001) 226]. In particular, it was found that both the tetrahedral- and octahedral covalent radii of manganese depend on a choice of the anion species in the Mn–chalcogen atom bond, and therefore they cannot be considered as the element constants for Mn.

The photoinduced electron transfer reactions in four similar donor–acceptor systems, N-ethyl carbazole (ECZ)-1,4-dicyanobenzene (DCB), 1,4,5,8,9-pentamethyl carbazole (PMC)-DCB, ECZ-1,2,4,5-tetracyanobenzene (TCNB) and PMC-TCNB have been studied to establish the effect of substitutions on the mechanistic pathways of electron transfer (ET) reactions. The initial spin states of the transients have been characterized by laser flash photolysis and magnetic field effect studies. The presence of more –CN groups in TCNB compared to DCB alters the ET pathways, by enhancing intersystem crossing. The temperature and free energy dependencies of these systems have been utilized to evaluate the process from the theoretical viewpoint.

The approximate CI method recently proposed by Maynau and Heully is similar to the A k procedure of Gershgorn and Shavitt. The A k and the related B k procedures are reviewed, some previously unpublished results are given, and new implementation plans are reported.

Graphical abstract, Highlights • Antivirals against SARS-CoV-2 are needed. • The papain-like protease represents an important target for antivirals. • We investigated tropane alkaloids from Schizanthus porrigens. • By molecular docking and MS simulations we identified two leads. • Shizanthine Z has favorable ADME properties and can be considered a lead., This paper presents identification of potential inhibitors of SARS-CoV-2 papain-like protease from tropane alkaloids from Schizanthus porrigens, using molecular docking method. Binding affinities were compared with those obtained with Lopinavir as a SARS-CoV-2 papain-like protease inhibitor. Overall, our findings indicate that Schizanthine Z binds to the SARS-CoV-2 papain-like protease with relatively high affinity and favorable ADME properties. Therefore, Schizanthine Z may represent an appropriate compound for further evaluation in antiviral assays.

Water dispersible 3-marcaptoproponic acid protected Mn2+@ZnSe QDs were applied for sensing hazardous mercury and lead ions, which acts as an acceptor for metal ions due to the strong interaction between the metal ions and thiol group (-SH). The photoluminescence (PL) intensity of Mn2+@ZnSe QDs was strongly quenched with Hg2+ and Pb2+ (0-100 μL). The average PL lifetime of Mn2+@ZnSe was shortened with Hg2+ concentrations whereas increased with Pb2+ concentrations. A filter paper-based sensor was also prepared and successfully tested for sensing via colorimetric and fluorometric detection methods. The system provided a new possibility for dual response ions detection in real samples.