An accuracy test method is proposed to reduce the amount of reagents used in the test and reduce the cost of spot checks and self-tests.
According to the requirements of dose accuracy test in ...standard atmospheric conditions in ISO 11608-1:2014, dose accuracy test is carried out for the same batch of reusable pen injector samples by using the test method proposed in this paper and the test method in relevant foreign research, and the data measured by the two methods are processed.
After experimental testing and analysis, the data measured by the two methods did not exceed the dose accuracy limit specified in the ISO standard. There was no significant difference between the two methods when the dose of 60 U and 30 U were tested, but there was significant difference when the dose of 1 U was tested.
Both methods can be used to evaluate dose accuracy, however, the method proposed in this paper can reduce the usage of drugs by 2/3, so it can reduce cost of supervised test.
As a simple and versatile method, diffusion driven Layer-by-Layer assembly (dd-LbL) is developed to assemble graphene oxide (GO) into three-dimensional (3D) structure. The assembled GO macrostructure ...can be reduced through a hydrothermal treatment and used as a high volumetric capacitance electrode in supercapacitors. In this report we use rGO framework created from dd-LbL as a scaffold for in situ polymerization of aniline within the pores of the framework to form rGO/polyaniline (rGO/PANI) composite. The rGO/PANI composite affords a robust and porous structure, which facilitates electrolyte diffusion and exhibits excellent electrochemical performance as binder-free electrodes in a sandwich-configuration supercapacitor. Combining electric double layer capacitance and pseudo-capacitance, rGO/PANI electrodes exhibit a specific capacitance of 438.8 F g−1 at discharge rate of 5 mA (mass of electrodes were 10.0 mg, 0.5 A g−1) in 1 mol L−1 H2SO4 electrolyte; furthermore, the generated PANI nanoparticles in rGO template achieve a higher capacitance of 763 F g−1. The rGO/PANI composite electrodes also show an improved recyclability, 76.5% of capacitance retains after recycled 2000 times.
Display omitted
•3D porous rGO is prepared by diffusion driven layer-by-layer assembly.•Polyaniline (PANI) nanoparticles are in-situ grown within the pores of 3D rGO.•As-prepared rGO/PANI was used as binder-free electrodes for supercapacitor.•The rGO/PANI exhibits capacitance of 438.8 F g−1 at 0.5 A g−1 in 1 M H2SO4.•PANI particles achieve a higher capacitance of 763 F g−1 at 0.5 A g−1.
Wireless traffic volume detectors play a critical role for measuring the traffic-flow in a real-time for current Intelligent Traffic System. However, as a battery-operated electronic device, ...regularly replacing battery remains a great challenge, especially in the remote area and wide distribution. Here, we report a self-powered active wireless traffic volume sensor by using a rotating-disk-based hybridized nanogenerator of triboelectric nanogenerator and electromagnetic generator as the sustainable power source. Operated at a rotating rate of 1000 rpm, the device delivered an output power of 17.5 mW, corresponding to a volume power density of 55.7 W/m3 (P d = P/V, see Supporting Information for detailed calculation) at a loading resistance of 700 Ω. The hybridized nanogenerator was demonstrated to effectively harvest energy from wind generated by a moving vehicle through the tunnel. And the delivered power is capable of triggering a counter via a wireless transmitter for real-time monitoring the traffic volume in the tunnel. This study further expands the applications of triboelectric nanogenerators for high-performance ambient mechanical energy harvesting and as sustainable power sources for driving wireless traffic volume sensors.
With unique water-repellent and self-cleaning properties, engineering metallic materials with superhydrophobicity endows them with greatly enhanced corrosion resistance. Herein, a facile and ...controllable one-step electrodeposition approach was employed to fabricate a superhydrophobic surface (SHPS) on an aluminum (Al) substrate as a barrier against corrosion media. The wettability, morphology, and chemical composition of the consequent SHPS were characterized by contact angle (CA), field-emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and energy dispersive spectroscopy (EDS), respectively. The anti-contamination and anticorrosion behaviors of the resultant SHPS were investigated by self-cleaning test, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS). The electrochemical results indicate that the resultant SHPS possessed greatly enhanced corrosion resistance, and were able to reduce the corrosion of a bare Al surface, with an inhibition efficiency of 99.96%. Furthermore, the as-fabricated SHPS maintained excellent durability and stability after air exposure, deionized water immersion, and 3.5 wt% NaCl solution immersion. We believe that SHPS fabricated by a versatile one-step electrodeposition approach would make it possible to develop engineering materials with durable self-cleaning and anticorrosion properties for use in rugged environments.
A facile one-step electrodeposition method was used to fabricate a hierarchical papillae-covered SHPS on an Al substrate with enhanced corrosion resistance (corrosion inhibition efficiency ~99.96%) and lotus-like self-cleaning effect.
We present for the first time approaches to 3D-printing of nanocellulose hydrogel scaffolds based on double crosslinking, first by in situ Ca
crosslinking and post-printing by chemical crosslinking ...with 1,4-butanediol diglycidyl ether (BDDE). Scaffolds were successfully printed from 1% nanocellulose hydrogels, with their mechanical strength being tunable in the range of 3 to 8 kPa. Cell tests suggest that the 3D-printed and BDDE-crosslinked nanocellulose hydrogel scaffolds supported fibroblast cells' proliferation, which was improving with increasing rigidity. These 3D-printed scaffolds render nanocellulose a new member of the family of promising support structures for crucial cellular processes during wound healing, regeneration and tissue repair.
The interaction between host and microorganism widely affects the immune and metabolic status. Indole and its derivatives are metabolites produced by the metabolism of tryptophan catalyzed by ...intestinal microorganisms. By activating nuclear receptors, regulating intestinal hormones, and affecting the biological effects of bacteria as signaling molecules, indole and its derivatives maintain intestinal homeostasis and impact liver metabolism and the immune response, which shows good therapeutic prospects. We reviewed recent studies on indole and its derivatives, including related metabolism, the influence of diets and intestinal commensal bacteria, and the targets and mechanisms in pathological conditions, especially progress in therapeutic strategies. New research insights into indoles will facilitate a better understanding of their druggability and application in intestinal and liver diseases.
Contact-electrification is a universal effect for all existing materials, but it still lacks a quantitative materials database to systematically understand its scientific mechanisms. Using an ...established measurement method, this study quantifies the triboelectric charge densities of nearly 30 inorganic nonmetallic materials. From the matrix of their triboelectric charge densities and band structures, it is found that the triboelectric output is strongly related to the work functions of the materials. Our study verifies that contact-electrification is an electronic quantum transition effect under ambient conditions. The basic driving force for contact-electrification is that electrons seek to fill the lowest available states once two materials are forced to reach atomically close distance so that electron transitions are possible through strongly overlapping electron wave functions. We hope that the quantified series could serve as a textbook standard and a fundamental database for scientific research, practical manufacturing, and engineering.
A novel triboelectric nanogenerator (TENG) is designed, based on flexible and transparent vertical‐strip arrays, for environmental wind‐energy harvesting. Given the low cost, simple structure, and ...wide applicability, the TENGs present a green alternative to traditional methods used for large‐scale wind‐energy harvesting.
As a member of the lead-halide perovskite family, inorganic perovskite CsPbBr3 exhibits excellent optical and electrical properties with higher stability to the environment. However, former efforts ...to obtain large-size CsPbBr3 single crystals with satisfactory quality using low temperature solution methods reached limited results. In this work, we have studied the growth of CsPbBr3 crystals using the antisolvent vapor-assisted crystallization (AVC) method. By adjusting the mole ratio of PbBr2 and CsBr, the phase diagram of the final products is acquired. Five regions are identified, including the Cs4PbBr6 single phase region, Cs4PbBr6 and CsPbBr3 two phases region, CsPbBr3 single phase region, CsPbBr3 and PbBr2·2(CH3)2SO metastable two phases region, and CsPbBr3 and PbBr2·2(CH3)2SO two phases region. Three methods are adopted to improve the size and crystalline quality of CsPbBr3. The growth rate is effectively tailored by diluting the antisolvent MeOH solution using DMSO to reduce the MeOH vapor pressure. Centimeter-size bright CsPbBr3 crystals have been obtained. The room temperature bandgap of CsPbBr3 is estimated at ∼2.29 eV by the transmission spectra. The photoluminescence spectra show two strong emission peaks, located at 530 and 555 nm, respectively, which are related to the free and bond excitons. The resistivity is as large as 2.1 × 109 Ω·cm. Hall effect measurements demonstrate the CsPbBr3 is p-type conductivity with a hole carrier concentration of 4.55 × 107 cm–3 and the mobility of 143 cm2 V–1 s–1. The resulting Au/CsPbBr3/Au device exhibits strong photoresponse to optical light, with an on–off ratio of two orders under a light emitting diode (∼1 mW/cm2) with a wavelength of 365–420 nm. Our research would shed more light on the growth and the photoresponse properties of CsPbBr3 crystals.
The double loop electrochemical potentiokinetic reactivation method was modified and applied to detect the susceptibility to intergranular corrosion of super austenitic stainless steel S32654 aged at ...1000 °C. The precipitation behavior was clarified, and the corresponding intergranular corrosion mechanism of aged S32654 was proposed. The microstructure demonstrated that σ phase, Cr2N and π phase nucleated at the initial stages of aging and gradually grew larger with increasing aging time. The degree of sensitization increased rapidly in the early stage of aging and then showed a slow increasing rate during long term aging stage, and no self-healing has been observed. Such modified double loop electrochemical potentiokinetic reactivation method could successfully characterize the relationship between microstructure evolution and intergranular corrosion susceptibility of S32654. The mechanism of intergranular corrosion was attributed to the Cr and Mo depletion adjacent to σ phase and π phase and the Cr depletion around Cr2N.
Display omitted
•Precipitation behavior of S32654 at nose temperature (1000 °C) is investigated.•A modified DL-EPR method is established to detect IGC susceptibility of S32654.•The degree of sensitization increases with aging time and no self-healing occurs.•Cr-depleted zone and Mo-depleted zone are observed adjacent to the precipitates.•The IGC of S32654 is caused by the Cr- and Mo-depleted zones.
PDF
