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61.
Vladimir Tereshin Aleksandr Bovda Vera Bovda Oleg Byrka Vladimir Chebotarev Vladimir Fedorchenko Igor Garkusha 《Vacuum》2006,80(11-12):1272
The results of film deposition of pure tungsten as well as intermetallic compound of NdFeB type on various substrates using planar ECR plasma source (with multipole magnetic field) developed in our laboratory are presented. The frequency of 2.45 GHz was generated within the magnetic system by two-slot antenna. The ions of ECR argon plasma are used for target sputtering. The main plasma parameters are density 1010 cm−3, Te15 eV, ions energy 20 eV, ion current density 3.5 mA/cm2 at the ultimate magnetron power. Under sputtering of Nd8Fe86B6 target the amorphous films with high adherence and thickness of 5 μm were formed on the substrate. The deposition rate of tungsten films (target biasing 900 V) was 0.59 nm/s. The fine-grained films with high adhesion were obtained. They were tested against heat loads up to 100 J/cm2 produced under irradiation of coatings with plasma streams. 相似文献
62.
Yasutaka Ohira Aleksandr Chekhovskiy Toshio Yamanoi Takashi Endo Hiroyuki Fujita Hiroshi Toshiyoshi 《Journal of the Society for Information Display》2009,17(5):419-422
Abstract— A fabrication technique and characteristics of high‐power‐handling microelectromechanical systems (MEMS) optical scanners for laser 3‐D volumetric‐image display application is reported. The MEMS scanner is designed to control the reflection of high‐power YAG‐laser beam by using the optomechanical combination of a dielectric‐film‐coated mirror cube and an electrostatic‐MEMS‐scanner platform. These hybrid‐type MEMS optical scanners have a stroke of about 20° at resonant frequencies of 600 Hz when a 45‐V pulse voltage is applied. 相似文献
63.
A versatile imaging-based method is presented for quantifying the transparency of materials based on “illumination diffusion” (ID), representing scattering- and refraction-induced change in the spatial distribution of transmitted light intensity. Samples are backlit through a graticule mask, with analysis performed by comparative evaluation of graticule images recorded as-is and viewed through a sample, mimicking visual perception. ID-haze is quantified as the reduction of contrast, while ID-sharpness is derived from imaged knife-edge acuity. Measurements are performed for diverse materials, including clarified polyolefins, silica-filled amorphous polymers, semicrystalline films, and etched polymer sheets. Comparisons with the respective haze and clarity values obtained using a common ASTM D1003 haze-meter are made in terms of their quantitative correlation and suitability for applications. In particular, unlike conventional instruments, ID-based analysis captures the variation of transparency with sample-to-object “airgap” distance. Gratifyingly, ID-haze generally features a one-to-one correlation with standard ASTM haze, when determined at a specific distance. The presented method also enables sensitive detection of local defects—differentiating them from large-area characteristics—and accurately extracts the contribution of luminescence to loss of transparency. ID-based method therewith offers unique opportunities for application- and airgap-specific transparency analysis, and advanced options for optical process- and quality control. 相似文献
64.
Liana R Azizova Tetiana V Kulik Borys B Palianytsia Aleksandr E Zemlyakov Viktoriya N Tsikalova Vasiliy Ya Chirva 《Nanoscale research letters》2014,9(1):234
In this study, chemical transformations of benzyl ester of О-(phenyl-2-acetamido-2,3-dideoxy-1-thio-β-d-glucopyranoside-3-yl)-d-lactoyl-l-alanyl-d-isoglutamine (SPhMDPOBn) on the fumed silica surface were examined, and the surface complex structure was characterized by temperature-programmed desorption mass spectrometry (TPD-MS), infrared spectroscopy (FTIR) and electrospray ion trap mass spectrometry (ES IT MS). Stages of pyrolysis of SPhMDPOBn in pristine state and on the silica surface have been determined. Probably, hydrogen-bonded complex forms between silanol surface groups and the C = O group of the acetamide moiety NH-(CH3)-C = O…H-O-Si≡. The thermal transformations of such hydrogen-bonded complex result in pyrolysis of SPhMDPOBn immobilized on the silica surface under TPD-MS conditions. The shifts ∆ν of amide I band (measured from 1,626 to 1,639 cm−l for SPhMDPOBn in pristine state) of 33 and 35 cm−l which occurred when SPhMDPOBn was immobilized on the silica surface may be caused by a weakening of the intramolecular hydrogen bonding of the SPhMDPOBn because the interaction with the silica surface as hydrogen bond with silanol groups is weaker than that in associates. 相似文献
65.
Dialkyl furan‐2,5‐dicarboxylates,epoxidized fatty acid esters and their mixtures as bio‐based plasticizers for poly(VInylchloride)
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Dialkyl furan‐2,5‐dicarboxylates and epoxidized fatty acid esters (EFAE) of varying molecular weights and volatilities, as well as their mixtures, were investigated as alternative plasticizers for poly(vinylchloride) (PVC). The EFAE utilized were epoxidized soybean oil (ESO) and epoxidized fatty acid methyl ester (e‐FAME). All plasticizers were compatible with PVC, with plasticization efficiencies usually increasing with decreasing molecular weights of the plasticizers (except in the case of ESO, which was remarkably effective at plasticizing PVC, in spite of its relatively high molecular weight). In comparison with phthalate and trimellitate plasticizers, the alternatives generally yielded improved balance of flexibility and retention of mechanical properties after heat aging, with particularly outstanding results obtained using 30?50 wt % e‐FAME in mixtures with diisotridecyl 2,5‐furandicarboxylate. Although heat aging characteristics of the plasticized polymer were often related to plasticizer volatilities, e‐FAME performed better than bis(2‐ethylhexyl) 2,5‐furandicarboxylate, and bis(2‐ethylhexyl) phthalate of comparatively higher molecular weights. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42382. 相似文献
66.
Alan Herbert Aleksandr Fedorov Maria Poptsova 《International journal of molecular sciences》2022,23(6)
Z-DNA binding protein (ZBP1) very much represents the nuclear option. By initiating inflammatory cell death (ICD), ZBP1 activates host defenses to destroy infectious threats. ZBP1 is also able to induce noninflammatory regulated cell death via apoptosis (RCD). ZBP1 senses the presence of left-handed Z-DNA and Z-RNA (ZNA), including that formed by expression of endogenous retroelements. Viruses such as the Epstein–Barr “kissing virus” inhibit ICD, RCD and other cell death signaling pathways to produce persistent infection. EBV undergoes lytic replication in plasma cells, which maintain detectable levels of basal ZBP1 expression, leading us to suggest a new role for ZBP1 in maintaining EBV latency, one of benefit for both host and virus. We provide an overview of the pathways that are involved in establishing latent infection, including those regulated by MYC and NF-κB. We describe and provide a synthesis of the evidence supporting a role for ZNA in these pathways, highlighting the positive and negative selection of ZNA forming sequences in the EBV genome that underscores the coadaptation of host and virus. Instead of a fight to the death, a state of détente now exists where persistent infection by the virus is tolerated by the host, while disease outcomes such as death, autoimmunity and cancer are minimized. Based on these new insights, we propose actionable therapeutic approaches to unhost EBV. 相似文献
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69.
Obabko AV Cassel KW 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2005,363(1830):1189-1198
Numerical solutions of the flow induced by a thick-core vortex have been obtained using the unsteady, two-dimensional Navier-Stokes equations. The presence of the vortex causes an adverse pressure gradient along the surface, which leads to unsteady separation. The calculations by Brinckman and Walker for a similar flow identify a possible instability, purported to be an inviscid Rayleigh instability, in the region where ejection of near-wall vorticity occurs during the unsteady separation process. In results for a range of Reynolds numbers in the present investigation, the oscillations are also found to occur. However, they can be eliminated with increased grid resolution. Despite this behaviour, the instability may be physical but requires a sufficient amplitude of disturbances to be realized. 相似文献
70.
Ryasnyansky A Palpant B Debrus S Ganeev R Stepanov A Can N Buchal C Uysal S 《Applied optics》2005,44(14):2839-2845
The nonlinear absorption of nanocomposite layers based on ZnO implanted with Cu+ ions with an energy of 160 keV in implantation doses of 10(16) and 10(17) ions/cm2 was investigated. The values of the nonlinear absorption coefficient were measured by the Z-scan method at a wavelength of 532 nm by use of nanosecond and picosecond laser pulses. Possible optical applications of these materials are discussed. 相似文献