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[en] Highlights: • Tencel fabrics acted as the substrates for ultra-low-cost electroless plating. • Comparative study of Co0-based and Ni0-based activation was conducted. • Co-Ni-P coatings with prominent conductivity and magnetism were obtained. • The electromagnetic parameters were evaluated from the experimental datum. - Abstract: The primary objective of this research work was to develop high-performance conductive fabrics with desired electromagnetic interference (EMI) shielding effectiveness (SE), excellent durability and improved corrosion resistance. Such conductive fabrics were fabricated by combining an ultra-low-cost electroless plating method with an alkoxy silane self-assembly technology, which involved successive steps of modification, activation, Co-Ni-P coating deposition and 3-aminopropyltrimethoxysilane (APTMS) thin coatings assembling. Malic acid (MA) was selected to modify the pristine Tencel (TS) substrates, and the probably interaction mechanism was investigated by FT-IR measurement. Co0 and Ni0 nanoparticles (NPs) were used as the activators to initiate electroless plating, respectively, and thereby two categories of Co-Ni-P coatings with different Co/Ni atomic ratio were obtained. Both of them presented compact morphologies and preferential (1 1 1) crystal orientation, which were validated by FE-SEM and XRD measurements. Owing to the lower square resistance and higher magnetic properties, the Co-Ni-P coated fabric activated by Co0 activator showed a higher EMI SE (18.2–40.1 dB) at frequency of 30–1000 MHz. APTMS thin coatings were then assembled on the top of alloy coated fabrics to act as anti-corrosion barriers. Electrochemical polarization measurement in 3.5 wt.% NaCl solution showed that top-APTMS coated conductive fabric exhibited a higher corrosion resistance than the one in absence of APTMS assembly. Overall, the whole process of fabrication could be performed in several hours (or less) without any specialized equipment, which shows a great potential as EMI shielding fabrics in mass-production.
[en] This paper focuses on the use of more now three kinds of gas-flow proportional counter, including physical parameters, plat curve, efficiency. Through the comparison, we found our production process, improve the production level of domestic counting tube, and can choose according to the demand of appropriate count. (authors)
[en] By analyzing the condition for the formation of bipolarons, we point out that the bipolaronic explanation for high-temperature superconducting ternary metal oxides, given in Ref. 1, is doubtful
[en] It focuses on the use of more now three kinds of gas-flow proportional counter, including physical parameters, plat curve, efficiency. Through the comparison, we found our production process, improve the production level of domestic counting tube, and can choose according to the demand of appropriate count. (authors)
[en] Highlights: • Electroless plating Cu-Co-P polyalloy was firstly fabricated onto polyethylene terephthalate (PET) substrate. • An etchant-free and amine-free UV/ozonolysis irradiation method UV/ozonolysis was effective for the transition from hydrophilic to hydrophobic of PET sheet. • A time-saving and cost-effective orthogonal experiment (L_9(3)"4) was utilized to optimize the plating conditions. • The optimized copper polyalloy possessed high corrosion resistance in three aggressive mediums including NaCl, NaOH and HCl, respectively. • The Cu-Co-P coated PET composite showed excellent electromagnetic interference shielding effectiveness (EMI SE > 99.999% at frequency ranging from 30 MHz to 1000 MHz). - Abstract: High corrosion resistant Cu-Co-P coatings were firstly prepared on polyethylene terephthalate (PET) substrate by electroless plating in combination with UV/ozonolysis irradiation under optimized cobalt sulfate heptahydrate concentration, pH value, plating temperature and time. The copper polyalloy/PET composite can be obtained in three steps, namely: (i) the generation of oxygen-containing functionalities (carboxylic groups) onto PET surface through UV irradiation combined with ozone, (ii) Cu seeding catalysts were obtained after being immersed into cupric citrate and NaBH_4 solutions subsequently, and (iii) Cu-Co-P polyalloy metallization using electroless plating bath. Attenuated total reflection fourier transformation infrared spectrometer (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), water contact angle measurement and energy dispersive X-ray analysis (EDAX) were utilized to track the surface changes during the whole process. The electroless plating conditions were optimized by an orthogonal experiment (L_9(3)"4) for Cu-Co-P coating as follows: CoSO_4·7H_2O addition of 0.08 M, pH value, plating temperature and time were set on 10.0, 35 °C and 25 min, respectively. Under the optimal conditions, copper polyalloy possessed high adhesive strength and the lowest surface resistance (8.06 Ω/sq), while maintaining reliability even after over 1000 times of bending and mechanical stress. The results of scanning electron microscope (SEM) and atomic force microscope (AFM) measurements showed that Cu-Co-P layer formed on PET surface was imparted with fine uniformity and high compactness. Electrochemical test revealed the optimized Cu-Co-P coatings exhibited high corrosion resistance in NaCl, NaOH and HCl solutions, respectively. The excellent electromagnetic interference shielding effectiveness (EMI SE >99.999% at frequency ranging from 30 MHz to 1000 MHz) of copper polyalloy/PET composites was confirmed by the spectrum analyzer. Therefore, this copper polyalloy will have potential applications in microelectronics packaging and coatings for anti-corrosion and electromagnetic interference shielding.
[en] The method used a portable radiation meter, inside the instrument using two high range and low range, high and low range of the measurement process is the key technology automatically converted. Conventional circuit using anodic conversion, high-voltage relays or other high-voltage switching device, The method uses cathode conversion circuit, the circuit by the transistor, low-voltage normally relay, The circuit has low voltage switch, high reliability, low power consumption (authors)
[en] This article is the application of nuclear instrumentation and research results, presented closed gas proportional counter of research, pre-trial preparation, the main performance test for detector test ideas. Preliminary preparation test now has been basically completed, ongoing pumping test inflated. (authors)
[en] Phosphatidylinositol 3-kinase (PI3K)/Akt signaling is commonly activated upon virus infection and has been implicated in the regulation of diverse cellular functions such as proliferation and apoptosis. The present study demonstrated for the first time that infectious bursal disease virus (IBDV), the causative agent of a highly contagious disease in chickens, can induce Akt phosphorylation in cultured cells, by a mechanism that is dependent on PI3K. Inhibition of PI3K activation greatly enhanced virus-induced cytopathic effect and apoptotic cell death as evidenced by cleavage of poly-ADP ribose polymerase and activation of caspase-3. Investigations into the mechanism of PI3K/Akt activation revealed that IBDV activates PI3K/Akt signaling through binding of the non-structural protein VP5 to regulatory subunit p85α of PI3K resulting in the suppression of premature apoptosis and improved virus growth after infection. The results presented here provide a basis for understanding molecular mechanism of IBDV infection.
[en] It is the application of nuclear instrumentation and research results, presented closed gas proportional counter of research, pre-trial preparation, the main performance test for detector test ideas. Preliminary preparation test now has been basically completed, ongoing pumping test inflated. (authors)
[en] TELL1 is the off-detector electronics acquisition readout board for the LHCb experiment. In the development of TELL1, three data stream systems are built to tri-crosscheck the complex VHDL implementation for the FPGAs employed by TELL1. This paper will introduce the tri-crosscheck platform as well as the way they are used in the testing. (authors)