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1.
The glass transition temperature (Tg) is a key parameter to investigate for application in nuclear waste immobilization in borosilicate glasses. Tg for several glasses containing iodine (I) has been measured in order to determine the I effect on Tg. Two series of glass composition (ISG and NH) containing up to 2.5 mol% I and synthesized under high pressure (0.5 to 1.5 GPa) have been investigated using differential scanning calorimetry (DSC). The I local environment in glasses has been determined using X-ray photoelectron spectroscopy and revealed that I is dissolved under its iodide form (I). Results show that Tg is decreased with the I addition in the glass in agreement with previous results. We also observed that this Tg decrease is a strong function of glass composition. For NH, 2.5 mol% I induces a decrease of 24°C in Tg, whereas for ISG, 1.2 mol% decreases the Tg by 64°C. We interpret this difference as the result of the I dissolution mechanism and its effect on the polymerization of the boron network. The I dissolution in ISG is accompanied by a depolymerization of the boron network, whereas it is the opposite in NH. Although ISG corresponds to a standardized glass, for the particular case of I immobilization it appears less adequate than NH considering that the decrease in Tg for NH is small in comparison to ISG.  相似文献   
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We describe a novel, easy and efficient combinatorial phage display peptide substrate-mining method to map the substrate specificity of proteases. The peptide library is displayed on the pVII capsid of the M13 bacteriophage, which renders pIII necessary for infectivity and efficient retrieval, in an unmodified state. As capture module, the 3XFLAG was chosen due to its very high binding efficiency to anti-FLAG mAbs and its independency of any post-translational modification. This library was tested with Factor-VII activating protease (WT-FSAP) and its single-nucleotide polymorphism variant Marburg-I (MI)-FSAP. The WT-FSAP results confirmed the previously reported Arg/Lys centered FSAP cleavage site consensus as dominant, as well as reinforcing MI-FSAP as a loss-of-function mutant. Surprisingly, rare substrate clones devoid of basic amino acids were also identified. Indeed one of these peptides was cleaved as free peptide, thus suggesting a broader range of WT-FSAP substrates than previously anticipated.  相似文献   
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Fluorescent nanodiamonds (fNDs) containing nitrogen vacancy (NV) centers are promising candidates for quantum sensing in biological environments. This work describes the fabrication and implementation of electrospun poly lactic‐co‐glycolic acid (PLGA) nanofibers embedded with fNDs for optical quantum sensing in an environment, which recapitulates the nanoscale architecture and topography of the cell niche. A protocol that produces uniformly dispersed fNDs within electrospun nanofibers is demonstrated and the resulting fibers are characterized using fluorescent microscopy and scanning electron microscopy (SEM). Optically detected magnetic resonance (ODMR) and longitudinal spin relaxometry results for fNDs and embedded fNDs are compared. A new approach for fast detection of time varying magnetic fields external to the fND embedded nanofibers is demonstrated. ODMR spectra are successfully acquired from a culture of live differentiated neural stem cells functioning as a connected neural network grown on fND embedded nanofibers. This work advances the current state of the art in quantum sensing by providing a versatile sensing platform that can be tailored to produce physiological‐like cell niches to replicate biologically relevant growth environments and fast measurement protocols for the detection of co‐ordinated endogenous signals from clinically relevant populations of electrically active neuronal circuits.  相似文献   
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It is shown that construction of the calibration characteristics of measuring devices may be reduced to expansion of these characteristics into Chebyshev polynomials. The coefficients of these polynomials (i.e., the parameters of the calibration characteristics) are determined by means of spectrum analyzers as the coefficients of the expansion into a Fourier series of the output signal of the device that arise when cosine signals arrive at the device 's input.Translated from Izmeritel'naya Tekhnika, No. 8, pp. 19–20, August, 1995.  相似文献   
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The materials based on polyethylene and poly(vinylchloride) inner tapes and polymeric bitumen mastic with the trade mark TRANSKOR used for the anticorrosion protection of steel underground pipelines are described. For the capital repair of oil pipelines, a special construction solution is offered. This structure is composed of a polymeric bitumen primer, polymeric bitumen mastic, and heat-shrinkable film.  相似文献   
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Storage/Logic Arrays (SLA's) represent a structured logic array approach to the design of VLSI sequential logic. Design for concurrent error detection and testability is complicated in these arrays by the presence of embedded memory elements and multiple levels of logic. A means of designing SLA's for ease of testability and concurrent error detection (CED) is provided in this paper. Test sets for static and dynamic CMOS circuits are described. Fault and error coverage is presented and performance and area costs are analyzed for example circuits. In addition, a means of implementing dynamic CMOS SLA's is presented and shown superior to previous NMOS, static CMOS, and dynamic CMOS approaches based upon power consumption and simplicity of design  相似文献   
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