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  • Author: Wei Qi x
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Abstract

In the paper, the famous Hermite–Hadamard integral inequality for convex functions is generalized to and refined as the ones for n-time differentiable functions which are s-convex in the second sense, and some known results are improved.

A set of edges X is subverted from a graph G by removing the closed neighbourhood N[X] from G. We denote the survival subgraph by G=X. An edge-subversion strategy X is called an edge-cut strategy of G if G=X is disconnected, a single vertex, or empty. The edge-neighbour-scattering number of a graph G is defined as ENS(G) = max{ω(G/X)-|X| : X is an edge-cut strategy of G}, where w(G=X) is the number of components of G=X. This parameter can be used to measure the vulnerability of networks when some edges are failed, especially spy networks and virus-infected networks. In this paper, we prove that the problem of computing the edge-neighbour-scattering number of a graph is NP-complete and give some upper and lower bounds for this parameter.

Abstract

Background: The purpose of an external quality assessment (EQA) is to evaluate the analytical capability of clinical laboratories, identify differences among the laboratories and improve analytical quality. Our EQA results show that the rates of unsatisfactory performance for thyroid hormone tests were the highest in all of our EQA programs. Therefore, the main purpose of this study was to investigate unsatisfactory results by comparing the analytical values of five routinely used analytical systems.

Methods: The Kruskal-Wallis and two-sample Kolmogorov-Smirnov tests were used to identify analytical differences among and between analytical systems, respectively.

Results: The rates of significantly different results compared to the total number of analytical results were 81.1%, 64.5%, 93.3%, 50.0% and 56.7% for free triiodothyronine, total triiodothyronine, free thyroxine, total thyroxine and thyroid-stimulating hormone, respectively.

Conclusions: Relatively large analytical differences between analytical systems were observed, especially when the analytical systems were used to measure free thyroid hormones.

Clin Chem Lab Med 2006;44:1363–6.

Abstract

Originating from the US, deferred prosecution agreements (“DPAs”) have made their way to the UK through the Crime and Courts Act 2013 and Singapore through the Criminal Justice Reform Act 2018. The Singapore model for approval of DPAs draws heavily from the UK and both require proof to a court that DPAs are in the “interests of justice” and that their terms are “fair, reasonable and proportionate” before DPAs can be approved. This paper considers the theoretical basis for the court’s approval of DPAs, critically examines the application of the tests for approval of DPAs in the UK and considers Singapore’s likely approach. Where appropriate, it also draws on the experience of the US and identifies lessons that can be learnt for Singapore.

Abstract

In this article, a new rotational extrusion processing system was adopted for manufacturing of polybutene-1 (PB-1) pipes, and the effects of mandrel rotation speed on their structures and mechanical performances were studied. The experimental results showed that besides the conventional axial extrusion flow field, a hoop shear stress field imposed to the melt, which was generated by the introduction of mandrel rotation, could lead the combined stress apart from the axial direction of the pipes to induce the molecular orientation deviated from the axial direction. Thus, the axial orientation of PB-1 was restrained, which was revealed by thermal shrinkage measurements and polarized infrared spectra. Moreover, it was also found and confirmed by scanning electron microscopy and two-dimensional wide-angle X-ray diffraction that orientation mainly existed in the amorphous region rather than the crystal region. Differential scanning calorimetry tests showed that the mandrel rotation could facilitate the formation of more perfect crystals and higher crystallinity. As a result, compared with the PB-1 pipe produced by conventional extrusion, the hoop strength of the PB-1 pipes manufactured at a mandrel rotation speed of 8 rpm increased from 20.2 to 24.9 MPa, achieving a mechanical balance in both axial and hoop directions.

Abstract

In order to provide the basis to efficiently reduce the energy consumption and improve the removal rate, the simultaneous removal processes of SO2 and NO in two pulsed discharge plasma systems (NO/SO2/N2/O2/H2O and NO/SO2/N2/O2) were simulated respectively, and then the removal characteristics of these two gas systems were analyzed. The results show that NO can be completely removed when the residence time is close to 1.3 s and SO2 removal rate is 61.5% when the residence time reaches 3 s in a system containing water vapor. When the system does not contain water vapor, NO removal rate is still much high, while SO2 removal rate is approximately zero, and its concentration is below 1 × 10-6 at all levels of O2 concentration. When the system contains water vapor and the residence time reaches 3 s, the concentrations of HNO3, HNO2, N2O and N2O5 are 102 × 10-6, 15 × 10-6, 35 × 10-6 and 19 × 10-6, respectively, while HSO3 concentration is approximately zero throughout the entire process and the removed SO2 is converted to H2SO4 completely. HO2 concentration is very small during the process. After NO is removed completely, H2O2 concentration rises from zero to 16 × 10-6 at the end of the process. When the system does not contain water vapor, trends of change in the concentrations of NO, NO2, N2O5 and N2O are almost the same as those in a system containing water vapor. When O2 concentration is increased, NO removal velocity will be faster and the peak of the concentration curve of NO2 will be higher. NO removing velocity is much faster in a system containing water vapor than that in a system without water vapor when both systems have almost the same O2 concentration.

Abstract

C9H9N5O7SZn, monoclinic, P21/n (no. 14), a = 13.632(3) Å, b = 7.1280(14) Å, c = 14.777(3) Å, β = 100.52(3)°, V = 1411.7 Å3, Z = 4, Rgt(F) = 0.0542, wRref(F2) = 0.1099, T = 293 K.