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Numerical simulations of liquid metal (LM) magnetohydrodynamic (MHD) flows in a prototypical dual coolant lead lithium (DCLL) blanket module have been performed under conditions relevant to a real LM blanket system, i.e. strong magnetic field of 5 T (Hartmann number Ha ∼ 104) and poloidal flow velocity of 0.1 m s−1 (Reynolds number Re ∼ 105). The proposed blanket model includes all essential sub-components of a real LM blanket: radial supply ducts, inlet and outlet manifolds, multiple poloidal ducts and a U-turn zone. The computations were performed using a DNS-like finite-volume code on a very fine mesh of ∼ 320 × 106 cells to accurately capture all flow features. Four cases have been simulated, including: Case 1 for electrically conducting walls, Case 4 for non-conducting walls, and Cases 2 and 3 with partial SiC FCIs electrical insulation of the blanket conduits using silicon carbide flow channel inserts placed at selected locations. In these four cases, the computed MHD flows were analyzed for: (1) MHD pressure drop, (2) flow distribution, (3) flows in particular blanket components, (4) 3D and flow development effects, and (5) unsteady flows. Many important conclusions have been made, regarding effectiveness of the FCI to reduce the MHD pressure drop, flow balancing in the parallel channels, characteristic flow patterns in all blanket sub-components, electromagnetic coupling between the flows, 3D MHD effects, flow development length, and unsteady effects. This study is limited to purely MHD flows. Next study will focus on a DCLL blanket with a volumetric heating. [ABSTRACT FROM AUTHOR]

Abstract: Numerical simulation of multi-phase flow is essential to evaluate the feasibility of a liquid protection scheme for the power plant chamber. The level set method is one of the best methods for computing and analyzing the motion of interface among the multi-phase flow. This paper presents a general formula for the second-order projection method combined with the level set method to simulate unsteady incompressible multi-phase flow with/out phase change flow encountered in fusion science and engineering. The third-order ENO scheme and second-order semi-implicit Crank–Nicholson scheme is used to update the convective and diffusion term. The numerical results show this method can handle the complex deformation of the interface and the effect of liquid–vapor phase change will be included in the future work. [Copyright &y& Elsevier]

Numerical simulations of liquid metal (LM) magnetohydrodynamic (MHD) flows in a prototypical dual coolant lead lithium (DCLL) blanket module have been performed under conditions relevant to a real LM blanket system, i.e. strong magnetic field of 5 T (Hartmann number Ha ∼ 104) and poloidal flow velocity of 0.1 m s−1 (Reynolds number Re ∼ 105). The proposed blanket model includes all essential sub-components of a real LM blanket: radial supply ducts, inlet and outlet manifolds, multiple poloidal ducts and a U-turn zone. The computations were performed using a DNS-like finite-volume code on a very fine mesh of ∼ 320 × 106 cells to accurately capture all flow features. Four cases have been simulated, including: Case 1 for electrically conducting walls, Case 4 for non-conducting walls, and Cases 2 and 3 with partial SiC FCIs electrical insulation of the blanket conduits using silicon carbide flow channel inserts placed at selected locations. In these four cases, the computed MHD flows were analyzed for: (1) MHD pressure drop, (2) flow distribution, (3) flows in particular blanket components, (4) 3D and flow development effects, and (5) unsteady flows. Many important conclusions have been made, regarding effectiveness of the FCI to reduce the MHD pressure drop, flow balancing in the parallel channels, characteristic flow patterns in all blanket sub-components, electromagnetic coupling between the flows, 3D MHD effects, flow development length, and unsteady effects. This study is limited to purely MHD flows. Next study will focus on a DCLL blanket with a volumetric heating. [ABSTRACT FROM AUTHOR]

Objective: To study the epidemiological characteristics and related factors of dyslipidemia among adult residents in Xinjiang Uygur Autonomous Region (Xinjiang) in 2013-2014. Methods: A total of 4 120 adult residents consisting of Han and Uygur group aged over 18 years old were selected by using a stratified cluster random sampling method in 8 counties of Xinjiang from 2013 to 2014. The related factors of dyslipidemia were collected by questionnaire and physical measurement. The total cholesterol, triglyceride, high-density lipoprotein cholesterol and low-density lipoprotein cholesterol were detected by enzyme method. Factors associated with dyslipidemia were analyzed by chi-squared test and a multivariate unconditioned logistic regression model adjusted for gender, urban or rural area, age-group, body mass index (BMI), central obesity, smoking, drinking, education attainment, diabetes mellitus and hypertension. Results: The prevalence of dyslipidemia was 45.00% (1 854 cases). The prevalence of dyslipidemia was higher in Uygur group (47.80% (977/2 044)) than that in Han group (42.24% (877/2 076)) (χ(2)=12.84, P< 0.001). The analysis showed that dyslipidemia was related with gender ( OR= 0.41, 95 %CI : 0.33-0.51), urban area ( OR= 0.54, 95 %CI : 0.39-0.76), BMI (overweight group ( OR= 1.52, 95 %CI : 1.18-1.96); obesity group ( OR= 2.20, 95 %CI : 1.64-2.96)), central obesity ( OR= 1.66, 95 %CI : 1.29-2.14) and diabetes mellitus ( OR= 1.49, 95 %CI : 1.06-2.11) in Uygur group. The analysis also showed that dyslipidemia was related with BMI (overweight group ( OR= 1.72, 95 %CI : 1.32-2.25), obesity group ( OR= 2.60, 95 %CI : 1.85-3.64)), central obesity ( OR= 1.45, 95 %CI : 1.13-1.87), smoking ( OR= 1.46, 95 %CI : 1.09-1.95), diabetes mellitus ( OR= 1.77, 95 %CI : 1.38-2.25) and hypertension ( OR= 1.62, 95 %CI : 1.31-2.00) in Han group. Conclusions: The prevalence of dyslipidemia in Xinjiang was higher than the national average prevalence. The prevalence of dyslipidemia in Uygur group was significantly higher than that in Han group. The gender, living area, BMI, central obesity and diabetes mellitus were risk factors of dyslipidemia in Uygur group, and BMI, central obesity, smoking, diabetes mellitus and hypertension were risk factors of dyslipidemia in Han group in Xinjiang.

Objective: To understand the HIV transmission and associated factors in newly reported HIV infected couples before diagnosis. Methods: The information about newly reported HIV infected couples in Yunnan, Guangxi, Sichuan, Henan and Xinjiang provinces (autonomous region) were collected from National HIV/AIDS Information System from 2011 to 2014. The infection order of the sero-concordant couples were determined. Logistic regression model was used to analyze the HIV transmission between couples and identify the associated factors. Cochran-Armitage trend analysis was conducted to understand the annual sero-concordant couple proportion. Results: A total of 48 931 HIV cases in couples were included in this study, among whom 12 051(24.6%) were sero-concordant couples, indicating HIV transmissions occurred between them. Multivariate logistic regression analysis showed that those who were females ( OR =1.98, 95% CI : 1.89-2.08), aged >45 years (45-59 yrs: OR =1.32, 95% CI : 1.23-1.42; >60 yrs: OR =1.72, 95% CI : 1.58-1.86), had educational level of middle school education or below (illiteracy and primary school: OR =1.33, 95% CI : 1.23-1.44; middle school: OR =1.19, 95% CI : 1.10-1.28), were farmers or migrate workers ( OR =1.23, 95% CI : 1.17-1.30), were infected through injecting drug use or heterosexual intercourse (injecting drug use: OR =1.33, 95% CI : 1.03-1.72; heterosexual intercourse: OR =3.65, 95% CI : 2.89-4.61), had CD 4 + T cells of <500 cells/μl (<200 cells/μl: OR =5.05, 95% CI : 4.62-5.52; 200-349 cells/μl: OR =3.58, 95% CI : 3.26-3.93; 350-500 cells/μl: OR =2.14, 95% CI : 1.94-2.36), reported unprotected sexual behaviors ( OR =1.56, 95% CI : 1.49-1.64), were more likely to infect their couples before diagnosis. The HIV transmission proportion between couples before diagnosis decreased significantly from 28.9% (2 631/9 102) in 2011 to 25.5% (3 009/11 787) in 2014 among those infected through heterosexual intercourse. Conclusion: The proportion of HIV transmission between couples before diagnosis varied among different populations. Behavior intervention and early HIV test promoting are needed to prevent HIV transmission between couples before diagnosis in populations at high risk for HIV infection. HIV infection cases should be included in the HIV care system after diagnosis as early as possible.

The concentrations of 17PCDD/F congeners as well as tetra- to octa-homologues were determined in 33 soil samples collected within a radius of 7 km from a municipal solid waste (MSW) incineration plant that is equipped with three fluidized bed incinerators (FBIs) of co-firing MSW with coal in Hangzhou, China. The total PCDD/F concentrations ranged from 0.39 to 5.04 pg I-TEQ g(-1) (54-285 pg g(-1)), with an average and a median value of 1.22 and 0.84 pg I-TEQ g(-1) (105 and 86 pg g(-1)), respectively. A systematic decrease of PCDD/F levels was observed with the increasing distances and with the decreasing downwind frequencies from the plant. The comparisons of homologue and congener patterns and multivariate analysis of soil and flue gas samples strongly indicated that most of the soil samples were influenced by the FBIs. Apart from the incineration plant, historical PCDD/F emissions of hazardous waste incinerator (HWI) and motor vehicles as well as the application of 1,3,5-trichloro-2-(4-nitrophenoxy) benzene (CNP) seemed to play an important role in soil samples adjacent to these potential sources.

Fly ash from municipal solid waste (MSW), medical waste (MW) and electrical power plant (EPP) incinerators were analyzed for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs). The study showed that the PCDD/F levels in fly ash were EPP

The potential of mechanochemical treatment (MC) to degrade PCDD/Fs contained in fly ash was tested via grounding with and without calcium oxide (CaO) under atmospheric pressure. Three types of fly ash collected from medical waste incineration were compared, originating either from rotary kiln fluidized bed multi-stage incinerator using activated carbon spray (FA1, FA2), or a simple stoker incinerator without activated carbon spray (FA3). In test I: CaO to FA1 mixed at ratio of 6-60% was milled at rotational speed of 350 rpm; in test II: FA2 and FA3 without CaO were milled at rotational speed of 400 rpm. The duration of the tests was 2h. The results from the present study indicate that (1) under two test conditions of with and without CaO, PCDD/Fs contained in real fly ash both can be degraded by mechanochemical treatment, (2) under condition of blending with CaO, the degradation efficiency of PCDD/Fs increased with increasing ratio of CaO, (3) the degradation efficiency of PCDD/Fs may increase with rotational speed increasing and (4) the destruction and dechlorination are major mechanism for PCDD/Fs degradation. These results show that mechanochemical treatment is a high potential technology for PCDD/Fs degradation in fly ash.

The levels and homologue profile of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) from stack gas of three typical fluidized bed incinerators co-firing municipal solid waste (MSW) with Chinese coal were measured. The PCDD/Fs emission was in the range of 0.0054-0.1961 ng I-TEQ/N m(3). Comparison of PCDD/Fs detection results by HRGC/HRMS and HRGC/LRMS suggested that it was feasible to detect fly ash with high PCDD/Fs concentration by HRGC/LRMS. Several factors on PCDD/Fs emission were discussed. The primary reason for the lower PCDD/Fs emission was the inhibition mechanism of relatively high sulfur in feeding coal on PCDD/Fs formation. The emission results also showed that there was no directly correlation between PCDD/Fs levels and CO, O(2) and HCl concentration in flue gas. It was estimated that about 0.1034 g I-TEQ was annually emitted to atmosphere from the tested three MSW incinerators (total daily treatment capacity is 800 tonnes MSW).