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1.
Nanomaterials (Basel) ; 13(24)2023 Dec 13.
Article in English | MEDLINE | ID: mdl-38133026

ABSTRACT

This study introduces a novel Ni/NiCr/NiCrAlSi composite coating to enhance the corrosion resistance of copper, particularly for its use in marine heat exchangers. Utilizing characterization techniques such as scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS), the paper investigates the coating's composition, structure, and corrosion resistance in 3.5 wt.% NaCl aqueous solutions. A significant focus is placed on the role of aluminum within the NiCrAlSi layer, examining its influence on the coating's structure and corrosion behavior. The results indicate that the NiCrAlSi layer with an aluminum content of 5.49 at.% exhibits the most improved corrosion resistance, characterized by the highest corrosion potential and a corrosion current density that is more than one order of magnitude lower compared to the Ni/NiCr coating. The effectiveness of this composite coating is attributed to its multilayer structure and the synergistic effect of alloying elements Cr, Al, and Si, which collectively inhibit corrosive medium penetration. These insights present the Ni/NiCr/NiCrAlSi coating as a promising candidate for copper protection in sea water environments, merging enhanced durability with cost-effectiveness.

2.
Materials (Basel) ; 16(14)2023 Jul 10.
Article in English | MEDLINE | ID: mdl-37512199

ABSTRACT

2 at.% Cu + 2 at.% Ni were co-doped in ZnO nanoparticles by a simple hydrothermal method, and then the modified nanoparticles were compounded into Cu-Ni alloy coatings using an electroplating technique. The effects of the current density (15-45 mA/cm2) on the phase structure, surface morphology, thickness, microhardness, corrosion resistance, and photocatalytic properties of the coatings were investigated. The results show that the Cu-Ni-Zn0.96Ni0.02Cu0.02O nanocomposite coatings had the highest compactness and the best overall performance at a current density of 35 mA/cm2. At this point, the co-deposition rate reached its maximum, resulting in the deposition of more Zn0.96Ni0.02Cu0.02O nanoparticles in the coating. More nanoparticles were dispersed in the coating with a better particle strengthening effect, which resulted in a minimum crystallite size of 15.21 nm and a maximum microhardness of 558 HV. Moreover, the surface structure of the coatings became finer and denser. Therefore, the corrosion resistance was significantly improved with a corrosion current density of 2.21 × 10-3 mA/cm2, and the charge transfer resistance was up to 20.98 kΩ·cm2. The maximum decolorization rate of the rhodamine B solution was 24.08% under ultraviolet light irradiation for 5 h. The improvement in the comprehensive performance was mainly attributed to the greater concentration of Zn0.96Ni0.02Cu0.02O nanoparticles in the coating, which played the role of the particle-reinforced phase and reduced the microstructure defects.

3.
Materials (Basel) ; 16(7)2023 Mar 29.
Article in English | MEDLINE | ID: mdl-37049041

ABSTRACT

Here, 2% Cu + 2% Ni co-doped ZnO nanoparticles were synthesized using the hydrothermal method and were used as particle reinforcements of Cu-Ni nanocomposite coatings prepared by electroplating technology. The effects of the added (Cu, Ni) co-doped ZnO nanoparticles (2-8 g/L) on the phase structure, surface morphology, thickness, microhardness, corrosion resistance, and photocatalytic properties of the coatings were investigated. The nanocomposite coatings have obvious diffraction peaks on the crystal planes of (111), (200), and (220), showing a wurtzite structure. The surface of the nanocomposite coatings is cauliflower-like, and becomes smoother and denser with the increase in the addition of nanoparticles. The grain size, thickness, microhardness, corrosion resistance, and photocatalytic properties of the nanocomposite coating reach a peak value when the added (Cu, Ni) co-doped ZnO nanoparticles are 6 g/L. At this concentration, the mean crystallite size of the coating reaches a minimum of 15.31 nm, and the deposition efficiency of the coating is the highest. The (Cu, Ni) co-doped ZnO nanoparticle reinforcement makes the microhardness reach up to 658 HV. The addition of nanoparticles significantly improves the corrosion resistance and photocatalytic properties of nanocomposite coatings. The minimum corrosion current density is 2.36 × 10-6 A/cm2, the maximum corrosion potential is -0.301 V, and the highest decolorization rate of Rhodamine B is 28.73% after UV irradiation for 5 h.

4.
J Anat ; 237(5): 933-940, 2020 11.
Article in English | MEDLINE | ID: mdl-32515838

ABSTRACT

The peripheral nervous system lacks lymphatic vessels and is protected by the blood-nerve barrier, which prevents lymphocytes and antibodies from entering the neural parenchyma. Peripheral nerve injury results in degeneration of the distal nerve and myelin degeneration causes macrophage aggregation, T lymphocyte infiltration, major histocompatibility complex class II antigen expression, and immunoglobulin G deposition in the nerve membrane, which together result in nerve edema and therefore affect nerve regeneration. In the present paper, we show myelin expression was absent from the sciatic nerve at 7 days after injury, and the expression levels of lymphatic vessel endothelial hyaluronan receptor 1 (LYVE-1) and Prospero Homeobox 1 (Prox1) were significantly increased in the sciatic nerve at 7 days after injury. The lymphatic vessels were distributed around the myelin sheath and co-localized with lymphatic endothelial cells. Prox1 induces the formation of new lymphatic vessels, which play important roles in the elimination of tissue edema as well as in morphological and functional restoration of the damaged nerve. This study provides evidence of the involvement of new lymphatic vessels in nerve repair after sciatic nerve injury.


Subject(s)
Homeodomain Proteins/metabolism , Lymphangiogenesis , Nerve Regeneration , Peripheral Nerve Injuries/metabolism , Sciatic Nerve/injuries , Tumor Suppressor Proteins/metabolism , Animals , Disease Models, Animal , Membrane Transport Proteins/metabolism , Mice , Myelin Sheath/metabolism , Nerve Crush , Peripheral Nerve Injuries/pathology , Random Allocation , Sciatic Nerve/metabolism , Sciatic Nerve/pathology
5.
RSC Adv ; 9(36): 20549-20556, 2019 Jul 01.
Article in English | MEDLINE | ID: mdl-35515541

ABSTRACT

NaV3O8 nanobelts were successfully synthesized for Li/Na-ion batteries and rechargeable aqueous zinc-ion batteries (ZIBs) by a facile hydrothermal reaction and subsequent thermal transformation. Compared to the electrochemical performance of LIBs and NIBs, NaV3O8 nanobelt cathode materials in ZIBs have shown excellent electrochemical performance, including high specific capacity of 421 mA h g-1 at 100 mA g-1 and good cycle stability with a capacity retention of 94% over 500 cycles at 5 A g-1. The good diffusion coefficients and high surface capacity of NaV3O8 nanobelts in ZIBs were in favor of fast Zn2+ intercalation and long-term cycle stability.

6.
Chinese Journal of School Health ; (12): 374-377, 2019.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-819171

ABSTRACT

Objective@#To understand the current situation of the lack of knowledge about sexual and reproductive health among female college students, and to provide a reference for conducting feasible and effective interventions to improve their reproductive health.@*Methods@#Female college students from a higher vocational college in Yantai were randomly sampled and questionnaires were conducted before and after the sexual and reproductive health education, 2 153 baseline questionnaires were obtained before intervention. After intervention for half a year, 2 110 valid questionnaires were obtained.@*Results@#After the intervention, female college students’ awareness of normal menstrual cycle, menstrual days, menstrual health knowledge, female ovulation time, ovulation and menstruation significantly improved(P<0.01). The proportion of female college students taking an open attitudes of towards to premarital sex increased, and the number of contraceptives was significantly increased during premarital sex, and the rate reported with the intention of unwanted pregnancies to help parents, friends, and teachers was increased significantly, and the rate of choosing abortion in the illegal clinic decreased significantly (P<0.05). After intervention, students were concerned about contraceptive knowledge, STD prevention, and human flow harm. The cognition was significantly improved(P<0.01).@*Conclusion@#Reproductive health education for female college students can have a good effect and significantly increase the awareness rate of related knowledge.

7.
Reprod Biomed Online ; 30(3): 275-80, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25596907

ABSTRACT

KIAA0319L, PXK and JAZF1 gene polymorphisms were investigated to determine whether they conferred susceptibility to unexplained recurrent pregnancy loss (URPL) in a group of Chinese Han patients. Genotyping and sequencing of the single nucleotide polymorphisms (SNP) rs2275247(A/G) in KIAA0319L, rs2176082(C/T) and rs6445975(G/T) in PXK and the rs1635852(C/T) in JAZF1 were carried out in 84 couples with URPL and 102 healthy couples with at least one live birth. Frequencies of the SNP rs2176082(C/T) in PXK gene were significantly different between women with URPL and control women: P < 0.05; OR 95% CI 0.530 (0.287 to 0.979); OR 95% CI 0.482 (0.254 to 0.911) but were not significantly different after Bonferroni correction. The frequencies of the SNP rs2176082(C/T) in PXK gene showed no difference between the husband of a woman with URPL and a control husband: OR 95% CI 1.494 (0.821 to 2.721); OR 95% CI 1.567 (0.841 to 2.921). No statistically significant differences were observed in the distribution of any genotype or allele frequency or any genetic model of the other three SNPs between couples with URPL and control couples. Therefore, the rs2176082(C/T) polymorphism of PXK might play a possible role in the development of URPL in Chinese Han women.


Subject(s)
Abortion, Spontaneous/genetics , Intracellular Signaling Peptides and Proteins/genetics , Models, Genetic , Neoplasm Proteins/genetics , Nerve Tissue Proteins/genetics , Nuclear Proteins/genetics , Protein Serine-Threonine Kinases/genetics , Abortion, Spontaneous/metabolism , Adult , Alleles , Asian People , Case-Control Studies , China , Co-Repressor Proteins , DNA-Binding Proteins , Family Characteristics , Female , Gene Frequency , Genetic Association Studies , Genetic Predisposition to Disease , Hospitals, University , Humans , Intracellular Signaling Peptides and Proteins/metabolism , Male , Neoplasm Proteins/metabolism , Nerve Tissue Proteins/metabolism , Nuclear Proteins/metabolism , Polymorphism, Single Nucleotide , Pregnancy , Protein Serine-Threonine Kinases/metabolism , Receptors, Cell Surface , Recurrence
8.
Eur J Obstet Gynecol Reprod Biol ; 181: 84-8, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25128867

ABSTRACT

OBJECTIVE: To investigate the association of tissue inhibitor of metalloproteinase (TIMP) gene polymorphisms with unexplained recurrent spontaneous abortions (URSA) in a well-defined group of Han Chinese couples. STUDY DESIGN: This is a case-control association study. Genomic DNA was extracted from peripheral blood samples from 84 couples with histories of three or more pregnancy losses and 69 age-matched healthy couples with at least one live birth and no histories of pregnancy loss. Polymerase chain reactions (PCRs) and sequencing with the fluorescent dye dideoxy-termination method were used to detect the rs4898 in TIMP-1, rs2277698 in TIMP-2, rs2234921 and rs5749511 in TIMP-3 and rs17035945 in TIMP-4 genotypes and allele frequencies. RESULTS: Neither the allele frequencies nor any of the genetic model of the five TIMP gene SNPs (i.e., TIMP-1-rs4898, TIMP-2-rs2277698, TIMP-3-rs5749511 and rs2234921, and TIMP-4-rs7035945) were significantly differences between the URSA couples and the control group. CONCLUSIONS: No evidence was found for any associations between the TIMP-1,-2,-3, or -4 genes SNPs with URSA in this Han Chinese Han.


Subject(s)
Abortion, Habitual/genetics , Asian People/genetics , Tissue Inhibitor of Metalloproteinase-1/genetics , Tissue Inhibitor of Metalloproteinase-2/genetics , Tissue Inhibitor of Metalloproteinase-3/genetics , Tissue Inhibitor of Metalloproteinases/genetics , Adult , Case-Control Studies , China/ethnology , Female , Gene Frequency , Genotype , Humans , Male , Polymorphism, Single Nucleotide , Pregnancy , Young Adult , Tissue Inhibitor of Metalloproteinase-4
9.
Zhonghua Nan Ke Xue ; 15(8): 700-2, 2009 Aug.
Article in Chinese | MEDLINE | ID: mdl-19852269

ABSTRACT

OBJECTIVE: To evaluate the inhibitory effect of Nandeshi, an acrosin inhibitor, on human acrosin activity. METHODS: We collected sperm samples from 10 healthy fertile men and cultured them with Nandeshi at 30 degrees C for 5 minutes at the concentrations of 0. 100, 0.120, 0.144, 0.173, 0.207, 0.249, 0.299, 0.358 and 0.430 mmol/L, with the controls treated with a well-known acrosin inhibitor N-alpha-p-tosyl-L-lysine chloromethylketone (TLCK) at 150.0, 189.8, 213.6, 240.3, 270.3, 304.1 and 342.1 mmol/L. Then we determined the residual activity of human acrosin by improved Kennedy assay. RESULTS: The residual activity of acrosin was negatively correlated with the Nandeshi concentration, and Nandeshi exhibited an inhibition rate about 800 times that of TLCK. CONCLUSION: Nandeshi has a powerful inhibitory effect on human acrosin, and improved Kennedy assay is a simple, practical and highly sensitive technique for the detection of human acrosin activity.


Subject(s)
Acrosin/antagonists & inhibitors , Acrosin/metabolism , Contraceptive Agents, Female/pharmacology , Enzyme Inhibitors/pharmacology , Humans , Male , Spermatozoa/drug effects , Tosyllysine Chloromethyl Ketone/pharmacology
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