[en] The sequential function specification method proposed first by Beck is considered as one of the most efficient methods for the inverse heat conduction problem (IHCP) which is extremely ill-posed and time-dependent. This method determines an open-quotes inverse solutionclose quotes advancing in a sequential fashion in time. The values estimated at any given time depend on the solution obtained previously. The main question connected with this method is the stability; i.e., the cumulative error in the solution must remain bounded at all time. Since the first paper of Beck in 1970, few theoretical stability analyses have been studied in the literature. The aim of this paper is to find the conditions under which this method is stable irrespective of the data measurements. For a 1D linear IHCP, we try to construct a sequence such that the coefficients α are independent of the data measured and the convergence of the series summation ^∝_i=1|X_i| guarantees the stability of the method. In other words, we need to find an adequate condition on a α, such that summation ^∝_i=1|X_i is convergent, implying that the method is stable. The values of α, depend on the discretization size h of the function to be determined q(t) and the sliding time horizon (or future time interval) τ of the method. The range of values of h and τ which give the values of α, such that the series summation ^∝_i=1|X_i | is convergent is established numerically. Under the stability condition, an error estimation of the Beck's method is derived. The approach presented could be also applied to multidimensional IHCPs, in which the coefficients α_i, and X_i are no longer scalar but become square matrices

[en] This paper explains the technology developed to produce Self-Assembled Mercaptan on Mesoporous Silica (SAMMS) for mercury removal from aqueous wastewater and from organic wastes. The characteristics of SAMMS materials, including physical characteristics and mercury loading, and its application for mercury removal and stabilization are discussed. Binding kinetics and binding speciations are reported. Preliminary cost estimates are provided for producing SAMMS materials and for mercury removal from wastewater. The characteristics of SAMMS in mercury separation were studied at PNNL using simulated aqueous tank wastes and actual tritiated pump oil wastes from Savannah River Site; preliminary results are outlined. 47 refs., 16 figs., 16 tabs

[en] OH-radical-induced dechlorination of pentachlorophenol (PCP) has been studies pulse and γ-radiolytically. OH radicals react with PCP by both electron transfer (53%) and addition followed by very rapid HCl-elimination to form phenoxyl radicals. The phenoxyl radicals decay to form products (e.g. chloranil) that unstable in alkaline aqueous solution and release some more Cl^-, therefore G(Cl^-) is high. Primary HPLC-MS analysis reveals that some quinones among the final products, whose toxicity remains unclear. Ozone can also oxidize PCP very rapidly, and this oxidation may destroy the benzene ring of PCP

[en] Highlights: • To fabricate high quality ZnS films need to promote the ion-by-ion process and restrain cluster-by-cluster process. • The complexation ability of tri-sodium citrate is stronger than that of hydrazine hydrate. • The nucleation density of nuclei determine the performance of ZnS thin films. -- Abstract: Zinc sulfide (ZnS) thin films were deposited on glass substrates using the chemical bath deposition (CBD) technique. The effects of different complexing agents (tri-sodium citrate, hydrazine hydrate) and their concentrations on the structure, composition, morphology, optical properties and growth mechanism of ZnS thin films were investigated. The results indicated that the chemical-bath-deposited ZnS thin films exhibit poor crystallinity and a high Zn/S atomic ratio with an average transmittance of 75% in the range of visible light. The ZnS thin films prepared using hydrazine hydrate as the complexing agent present a more compact surface, a smaller average particle size, and a sharper absorption edge at 300–340 nm compared with those prepared using tri-sodium citrate. Based on our experimental observations and analysis, we conclude that the predominant growth mechanism of ZnS thin films is an ion-by-ion process. The nucleation density of Zn(OH)₂ nuclei on the substrate in the initial stage produces the different morphologies and properties of the ZnS thin films prepared using the two complexing agents

[en] Polyaniline/Nafion and polypyrrole/Nafion composite membranes, prepared by chemical polymerization, are studied by infrared and nuclear magnetic resonance spectroscopy, and scanning electron microscopy. Differences in vanadium ion diffusion through the membranes and in the membranes area specific resistance are linked to analytical observations that polyaniline and polypyrrole interact differently with Nafion. Polypyrrole, a weakly basic polymer, binds less strongly to the sulfonic acid groups of the Nafion membrane, and thus the hydrophobic polymer aggregates in the center of the Nafion channel rather than on the hydrophilic side chains of Nafion that contain sulfonic acid groups. This results in a drastically elevated membrane resistance and an only slightly decreased vanadium ion permeation compared to a Nafion membrane. Polyaniline on the other hand is a strongly basic polymer, which forms along the sidewalls of the Nafion pores and on the membrane surface, binding tightly to the sulfonic acid groups of Nafion. This leads to a more effective reduction in vanadium ion transport across the polyaniline/Nafion membranes and the increase in membrane resistance is less severe. The performance of selected polypyrrole/Nafion composite membranes is tested in a static vanadium redox cell. Increased coulombic efficiency, compared to a cell employing Nafion, further confirms the reduced vanadium ion transport through the composite membranes.

[en] By referring to the supervision management experience of other power plants, the nuclear safety supervision mode of daily work and overhaul, the organization, program system, qualification, training and authorization of the nuclear safety supervisor of Hainan Nuclear Power Plant is determined, which is better for the internal supervision of the nuclear safety level. (author)

[en] The Compton detector, with fast time response, linear range over many orders of magnitude and low sensitivity to X-ray fluxes, can be used to measure the dose of time resolved X-ray, whose sensitivity is decided by the materials and dimensions of its collector, dielectric and metal case. Since the detector dimension is energy dependent, there will be an optimal dimension for a detector to measure Bremsstrahlung X-ray dose. Monte-Carlo method was used to design a Compton detector which will be used to measure the Bremsstrahlung X-ray dose produced by the Dragon-I accelerator. The Bremsstrahlung spectrum of Dragon-I was computed by MCNP program, as well as the Compton electron number as a function of plexiglass thickness, aluminum case thickness and plomb collector thickness. According to the calculated results an optimal Compton detector has been designed. Its energy response of sensitivity was calculated and the results is not as good as expected. Thus the detector was modified with aluminum in front of the collector and the calculated sensitivity for Bremsstrahlung produced by Dragon-I is improved to 6.86 x 10¹¹ (C/kg)^-1. (authors)

[en] Objective: To investigate the clinical significance of changes of plasma ET and serum TNF levels after operation in patients with cataracts. Methods: Plasma ET and serum TNF levels were detected with RIA in 32 patients with cataracts both before and after operation as well as in 30 controls. Results: Before operation, the plasma ET and serum TNF levels in patients with cataract were significantly higher than those in controls (P<0.01). One month after operation the plasma ET and serum TNF levels dropped to within normal ranges (P>0.05). Conclusion: Plasma ET and serum TNF levels were closely related to the disease process of cataract and were of prognostic value. (authors)

[en] Two interesting carbon nanostructures, the double helices and the nanobraids, have been synthesized by pyrolysis of acetone at 715 deg. C, using iron nanoparticles as catalysts. The double helix was formed by two nanofibers, strictly coiled together with a strikingly constant pitch. Such a rope-like structure usually extended hundreds of microns in length, and provided excellent strength, stability and flexibility. The nanobraids appeared to be partially rolled up from carbon layers. Electron microscopy was applied to characterize these carbon forms

[en] Since the Hainanareahas the typhoon, especially the super typhoon, it is particularly urgent to prevent events similar to the Fukushima accident. We discussed the supervision methods of post-Fukushima improvement items in the unit construction stage, normal operation stage, and accident conditions in order to further improve nuclear safety level of Hainan nuclear power plant. (author)