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Purpose: The purpose of this paper is to investigate the interfacial conductivity and corrosion resistance of the Ni–P/Ti4O7 composite coating that is deposited on a carbon steel substrate as bipolar plates for proton exchange membrane fuel cells. Design/methodology/approach: The Ni–P/Ti4O7 coating was prepared by electroless plating. Scanning electron microscopy, white light interference, energy dispersive spectrometry and X-ray diffraction were used, respectively, to study the surface morphology, chemical composition and phase composition of coated samples. Electrochemical impedance spectroscopy, potentiodynamic and potentiostatic polarization were used to test the electrochemical performance and corrosion behavior. The interfacial contact resistance (ICR) was measured via the standard method. Findings: The surface of the Ni–P/Ti4O7 coating is complete and dense and without obvious defects. The electrochemical test results show that the Ni–P/Ti4O7 coating provides better corrosion resistance than the Ni–P coating and substrate. Compared with the Ni–P coating, the ICR of the Ni–P/Ti4O7 coating is lower by about 82.7%. This is because the coating has more conductive contact points. The more exciting thing is that the ICR of the Ni–P/Ti4O7 coating only increases to 12.38 mΩ·cm2 after 5 h of polarization. Originality/value: This paper provides a method for achieving surface modification of metal bipolar plates. Introducing Ti4O7 particles in the Ni–P layer reduces the contact resistance before and after polarization while ensuring good corrosion resistance. [ABSTRACT FROM AUTHOR]

Fe3O4@polydopamine@polyamidoamine (Fe3O4@PDA@PAMAM) core–shell nanocomposites were successfully fabricated through a monodispersed Fe3O4 nanoflower synthesis, PDA modification and PAMAM grafting. The as-prepared single Fe3O4@PDA@PAMAM nanocomposite possesses a high relevant saturation magnetization (Ms) (30.25 emu g−1), while the coercivity (Hc) (10.85 Oe) and retentivity (Mr) (0.9062 emu g−1) were extremely low. The obtained Fe3O4@PDA@PAMAM has an adsorption capacity as high as 97.18 mg g−1 for Cu(ii), and the adsorption process is in conformity with pseudo-second-order kinetics and the Langmuir isotherm model. Moreover, the effect of pH and thermodynamics of the adsorption process is also discussed briefly. [ABSTRACT FROM AUTHOR]

Efficient white-polymer-light-emitting devices (WPLEDs) have been fabricated with a single emitting layer containing a hole-transporting host polymer, poly( N-vinylcarbzole), and an electron-transporting auxiliary, 1,3-bis[(4- tert-butylphenyl)-1,3,4-oxadiazolyl]-phenylene, codoped with two phosphorescent dyes: Iridium(III)bis (2-(4,6-difluorophenyl)-pyridinato-N,C2′) picolinate (FIrpic) and home-made Ir-G2 for blue and red emission, respectively. With the structure of ITO/PEDOT:PSS 4083(40 nm)/emission layer(80 nm)/Ba(4 nm)/Al(120 nm), the device showed a maximal luminous efficiency (LE) of 13.5 cd A(corresponding to an external quantum efficiency (EQE) of 6.8%), and a peak power efficiency (PE) of 6.5 lm W at 6.0 V. Meanwhile, the device exhibited pure white emission with Commission Internationale de l'Eclairage (CIE) coordinates of (0.34, 0.35) at a current density of 12 mA cm, which is very close to the equi-energy white point with CIE coordinates of (0.33, 0.33). The device performance can be further optimized when more balanced hole/electron injection is achieved by incorporating a lower conducting type anode buffer layer (PEDOT:PSS) and incorporating poly[(9,9-bis(3′-( N,N-dimethylamino) propyl)-2,7-fluorenene)- alt-2,7-(9,9-dioctyfluorene)] (PFN) as an electron injection layer at the cathode. The optimized device showed an LE of 24.6 cd A (with an EQE of 14.1%), while the peak power efficiency reached 12.66 lm W. Moreover, the WPLEDs showed good electroluminescence (EL) stability over a wide range of operating current density and luminance. [ABSTRACT FROM AUTHOR]

An extremely narrow-band-gap conjugated polymer poly(5,7-bis(4-decanyl-2-thienyl)thieno[3,4-b]diathiazole-thiophene-2,5) (PDDTT) (Eg≈1.01 eV) was synthesized by Stille coupling reaction, which absorbs the light from 330–1220 nm in solid thin film and shows good solution processibility. The polymeric photovoltaic cells based on PDDTT/[6,6]-phenyl-C61-butyric acid methyl ester blend show the short circuit density of 0.83 mA/cm2, open current voltage of 0.35 V, and photocurrent spectra response from 330 to 1100 nm under AM 1.5 simulator (100 mW/cm2). [ABSTRACT FROM AUTHOR]

Fe 2 O 3 is one of the most important lithium storage materials and has attracted increasing interest owing to its good capacity in theory, abundant reserves, and better security. The utilization of Fe 2 O 3 materials is hampered by their inferior cycle performance, low rate performance, and restricted composite variety. Herein, the heterostructure of Fe 2 O 3 @SnO 2 with hexahedral structure was manufactured by two- step hydrothermal strategy, while the SnO 2 nanopillars were epitaxially grown in six faces, not in the twelve edges of hexahedral Fe 2 O 3 cubes, which comes from maximizing lattice matching on the six surfaces of Fe 2 O 3 . Furthermore, the experimental results prove that the hexahedral Fe 2 O 3 @SnO 2 heterostructure exhibits remarkably enhanced electrochemical reversibility and reaction kinetics and delivers an impressive initial discharge capacity (1742 mA h g -1 at 4 A g -1 ), great rate performance (565 mA h g -1 at 5 A g -1 ), and stable long-term durability (661 mA h g -1 after 4000 cycles at 4 A g -1 ) as an anode for LIBs. The result of the finite element mechanical simulation further indicates that the SnO 2 nanopillars grow on the six surfaces but not on the twelve edges of the hexahedral Fe 2 O 3 cube, which would provide great rate performance and long-term stability. This study underlines the merits of the heterostructure and offers a useful design routine for superior electrode materials in LIBs.

Rational design of monomer sequence for desired properties is challenging. This study investigates the effect of monomer distribution of double hydrophilic copolymers (DHCs) with electron-rich units on cluster triggered emission (CTE) capacity. By means of combining latent monomer strategy, reversible addition fragmentation chain transfer (RAFT) polymerization and selective hydrolysis technology, the random, pseudo di-block and the gradient DHCs consisting of pH-responsive polyacrylic acid (PAA) segments and thermo-responsive poly(N-isopropylacrylamide) (PNIPAM) segments were successfully synthesized in a controlled manner. Moreover, the gradient DHCs showed a tremendously increased luminescent intensity due to the distinct hydrogen-bonding interaction compared to random and pseudo di-block DHCs. To the best of our knowledge, this is the first reported the direct correlation between luminescent intensity and sequence structure of non-conjugated polymer. Meanwhile, thermo and pH dual-responsive clusteroluminescence could be easily performed. This work demonstrates a novel and facile method to tailor the hydrogen-bonding for the stimuli-responsive light-emitting polymers., (© 2023 Wiley-VCH GmbH.)

Background: Colorectal cancer (CRC) is the most common gastrointestinal malignancy. And probiotics may have the function of preventing colon cancer. The aim of this study was to investigate the inhibitory effects of a probiotic mixture on colorectal cancer and its potential mechanisms., Methods: The effects of the probiotic mixture on proliferation and metastasis of mouse colon cancer CT26 cells were assessed by probiotics and cells co-culture assay, Cell Counting Kit-8 assay, colony formation assay, wound-healing assay, as well as migration and invasion assays. And CT26 cells were also transplanted into BALB/c mice to construct transplanted tumor animal model. The mice were randomly divided into two groups, control group and probiotic mixture intragastric administration group, after injection 21 days the tumor size and infiltration of immune cells in the tumor or spleen tissues were analyzed by hematoxylin and eosin (HE) and immunohistochemistry (IHC) staining., Results: The probiotic mixture significantly inhibited the proliferation, invasion, and migration ability of CT26 cells compare to the control cells (P<0.05). In the animal experiments, the tumor volume of mice that had been fed the probiotic mixture was significantly smaller than that of the control group (P<0.05). Compared with control mice, more apoptotic cells and infiltration of immune cells were showed in the tumor tissues of the mice treated with the probiotic mixture, and an increased number of CD8+ cells in the tumor and spleen tissues but no significant change in tissues., Conclusions: These results suggested that the probiotic mixture could inhibit the growth of CT26 tumors and induce an immune response in vivo . The probiotic mixture also inhibited the invasion, migration, and proliferation ability of CT26 cells in vitro ., Competing Interests: Conflicts of Interest: All authors have completed the ICMJE uniform disclosure form (available at http://dx.doi.org/10.21037/jgo-20-573). The authors have no conflicts of interest to declare., (2020 Journal of Gastrointestinal Oncology. All rights reserved.)

Objective: To investigate the relationship between vitamin D binding protein gene rs2282679 A/C polymorphism with blood vitamin D levels., Methods: A total of 286 eligible subjects were selected from one university in Hebei Province. Serum 25-hydroxylated vitamin D levels were measured by liquid chromatography-mass spectrometry, and gene chip was used for genotyping of rs2282679 locus. Statistical analysis was performed using R software., Results: A total of 285 participants in the study completed the experiment, and result indicated that the distribution of the rs2282679 locus A/C polymorphism in the participants was consistent with the Hardy-Weinberg equilibrium. The genotype of rs2282679 was significantly associated with serum vitamin D insufficiency and deficiency(P=0. 031). Allele A was a risk factor for vitamin D insufficiency and deficiency. The OR value of allele C relative to A was 0. 65, and the genetic pattern of allele C relative to A was dominant(P=0. 03)., Conclusion: The vitamin D-binding protein gene rs2282679 was significantly associated with serum vitamin D insufficiency and deficiency in college students, and A-allele is a risk factor accounting for vitamin D insufficiency and deficiency in college students.

Objective: To investigate curative effect and importance of radiofrequency thermocoagulation onsemilunar ganglion of aged patients with recurrent trigeminal neuralgia., Method: 112 cases with recurrent trigeminal neuralgia were performed with radiofrequency thermocoagulation on semilunar ganglion by puncture through skin under local anesthesia., Result: The maintaining effective duration in 112 cases was 7.3 ± 1.3 years after primary therapy. After the first thermocoagulation, 89.28% (100/112) patients got the relief from pain immediately, 8 (7.14%) cases also recieved the same effect after twice treatment. However two cases (2.6%) had no effects. The total effective rate was 98.21%. During five follow-up years, VAS scores, dose of carbamazepine and satisfaction were better than those before the treatment. The effective rate was still over 57.5% within three years after the treatment. The recurrent risk increased obviously from 40 months after the treatment by Kaplan-Meier method., Conclusion: Semilunar ganglion of radiofrequency thermocoagulation was an ideal option for old-age patients with trigeminal neuralgia. It can be performed repeatedly.

Background: To explore the significance of lung biopsy through CT-guided percutaneous paracentesis in the diagnosis of space-occupying lesions of the lung., Methods: Thirty-five patients with space occupying lesions of the lung underwent lung biopsy through CT-guided percutaneous paracentesis and DLTRA-CUT 16G, 18G or 20G soft-tissue-cutting biopsy needles and PICKER IQ computerized tomograph were used., Results: Of the 35 patients, 26 were confirmed by pathological examination to suffer from primary malignant tumor, 1 from metastatic carcinoma, 3 from tuberculosis and 3 from inflammatory pseudotumor. No definite diagnosis was made in two patients. The diagnostic rate was 94.3%. After operation, minor pneumothorax occurred in 5 cases and traces of blood in sputum in 2 cases, however, they didn't need any treatment., Conclusions: Lung biopsy through CT-guided percutaneous paracentesis is a safe and practical technique and may be widely used in hospitals if conditions permit.