Simulation and experimental study on the air jet pulverization of TiC-containing slag

Process of “high temperature carbonization and low temperature chlorination”, which was considered to be one of the most promising technologies, could extracte more than 70% titanium from the furnace slag containing TiO2 10% - 30%. TiC-containing slag was the product of high temperature carbonization, and to meet the requirement of the following chlorination process, it needs to be crushed and grounded to a suitable size distribution. The air jet pulverization of TiC-containing slag was studied in this paper. On the one hand, By CFD numerical simulation, the distribution regularity of nozzle flow field about the main crushing equipment was obtained with different throat diameters and crushing gas pressures. On the other hand, the influences of nozzle throat diameter, crushing pressure, and collision angles on the particle size of the powder were studied by experiment. With the better parameters, the particle size distribution of the product powder was uniform

Prevalence of Depression in Older Nursing Home Residents in High and Low Altitude Regions: A Comparative Study

Objective: Depressive symptoms (depression hereafter) is common in older adults, and closely associated with environmental factors. This study compared the prevalence of depression in older adults living in high-altitude and low-altitude regions, and their association with quality of life (QOL).Method: A total of 632 older nursing home residents were included, with 425 participants living in low-altitude and 207 participants living in high-altitude regions. Depression and QOL were assessed using standardized instruments.Results: The prevalence of depression was 26.9% (95% CI: 23.43–30.37%) in the whole sample of older nursing home residents, with 11.1% (95% CI: 8.01–14.05%) in those living in low-altitude and 59.4% (95% CI: 52.68–66.17%) in those living in high-altitude regions. Multiple logistic regression analysis revealed that living in low-altitude region (P < 0.001, OR = 0.07, 95% CI: 0.04–0.12) was associated with lower risk of depression, while perception of poor health status (P < 0.001, OR = 3.86, 95% CI: 1.98–7.54) and having insomnia (P < 0.001, OR = 4.76, 95% CI: 2.99–7.56) were associated with higher risk of depression. QOL was significantly lower in physical (F(1,632) = 35.421, P < 0.001), psychological (F(1,632) = 20.777, P < 0.001), social (F(1,632) = 8.169, P < 0.001) and environmental domains (F(1,632) = 11.861, P < 0.001) in those with depression.Conclusion: Depression was common in older nursing home residents especially those living in the high-altitude region. Considering the negative impact of depression on QOL and functional outcomes, routine screening and timely treatment of depression should be implemented in this population

PeerJ

BACKGROUND: Sleep disturbance is associated with a number of negative adverse outcomes. This study examined the prevalence of sleep disturbance and its association with demographic and clinical characteristics and quality of life (QOL) in psychiatric nurses in China. METHODS: This is a multi-center, cross-sectional study involving 11 psychiatric hospitals in China. Three types of sleep disturbance (difficulty initiating sleep (DIS), difficulty maintaining sleep (DMS) and early-morning awakening (EMA)) and QOL were measured by standardized questions or instruments. RESULTS: A total of 1,847 psychiatric nurses participated. The overall prevalence of at least one type of sleep disturbance was 71.5% (95% CI [69.3-73.5]); the prevalence of DIS, DMS and EMA was 58.5% (95% CI [56.2-60.8]), 53.7% (95% CI [51.4-56.0]) and 54.6% (95% CI [52.3-56.9]), respectively. Nurses with sleep disturbance had significantly lower QOL in physical (F ((1, 1,846)) = 219.12, P \textbackslashtextless 0.001), psychological (F ((1, 1,846)) = 72.18, P \textbackslashtextless 0.001), social (F ((1, 1,846)) = 37.57, P \textbackslashtextless 0.001) and environmental domains (F ((1, 1,846)) = 95.45, P \textbackslashtextless 0.001). Multivariable logistic regression analyses revealed that shift work (DIS, OR = 1.6, 95% CI [1.28-1.98]; DMS, OR = 1.2, 95% CI [1.001-1.54]; EMA, OR = 1.3, 95% CI [1.02-1.58]) and alcohol use (DIS, OR = 1.8, 95% CI [1.46-2.32]; DMS, OR = 1.8, 95% CI [1.43-2.23]; EMA, OR = 1.7, 95% CI [1.33-2.07]) were positively associated with sleep disturbance, while higher monthly income (DIS, OR = 0.5, 95% CI [0.38-0.75]; DMS, OR = 0.7, 95% CI [0.51-0.98]) was negatively associated with sleep disturbance. CONCLUSION: Sleep disturbance was common among nurses in psychiatric hospitals in China, particularly those on shifts and having alcohol use. Health authorities should develop effective measures to reduce risk of sleep disturbance in this population

Single Allocation Hub-and-spoke Networks Design Based on Ant Colony Optimization Algorithm

Abstract: Capacitated single allocation hub-and-spoke networks can be abstracted as a mixed integer linear programming model equation with three variables. Introducing an improved ant colony algorithm, which has six local search operators. Meanwhile, introducing the "Solution Pair" concept to decompose and optimize the composition of the problem, the problem can become more specific and effectively meet the premise and advantages of using ant colony algorithm. Finally, location simulation experiment is made according to Australia Post data to demonstrate this algorithm has good efficiency and stability for solving this problem

Single Allocation Hub-and-spoke Networks Design Based on Ant Colony Optimization Algorithm

Capacitated single allocation hub-and-spoke networks can be abstracted as a mixed integer linear programming model equation with three variables. Introducing an improved ant colony algorithm, which has six local search operators. Meanwhile, introducing the "Solution Pair" concept to decompose and optimize the composition of the problem, the problem can become more specific and effectively meet the premise and advantages of using ant colony algorithm. Finally, location simulation experiment is made according to Australia Post data to demonstrate this algorithm has good efficiency and stability for solving this problem

Simulation and experimental study on the air jet pulverization of TiC-containing slag

Process of “high temperature carbonization and low temperature chlorination”, which was considered to be one of the most promising technologies, could extracte more than 70% titanium from the furnace slag containing TiO2 10% - 30%. TiC-containing slag was the product of high temperature carbonization, and to meet the requirement of the following chlorination process, it needs to be crushed and grounded to a suitable size distribution. The air jet pulverization of TiC-containing slag was studied in this paper. On the one hand, By CFD numerical simulation, the distribution regularity of nozzle flow field about the main crushing equipment was obtained with different throat diameters and crushing gas pressures. On the other hand, the influences of nozzle throat diameter, crushing pressure, and collision angles on the particle size of the powder were studied by experiment. With the better parameters, the particle size distribution of the product powder was uniform

Diagnosis of Swine Toxoplasmosis by PCR and Genotyping of Toxoplasma gondii from pigs in Henan, Central China

Abstract Background Toxoplasma gondii, a widely prevalent protozoan parasite, causes serious toxoplasmosis infections in humans and other animals. Among livestock, pigs are susceptible to T. gondii infection. Despite Henan being one of the biggest pig-raising provinces in China, little information exists on the epidemiology of toxoplasmosis in this location. Therefore, we molecularly characterized DNA samples from pigs in Henan. A total of 1647 samples, including 952 from dead piglets, 478 from seriously sick fattening pigs and 217 from abortion sows, were collected from different animal hospitals or pig farms from 10 different cities in Henan (2006–2008). Each pig corresponded to a separate pig farm. DNA was extracted from 3 to 5 g of the most severely affected pig tissue (liver, spleen, lung, hilar lymph nodes and amniotic fluid) after postmortem examination. The presence of the T. gondii B1 gene was detected using nested polymerase chain reactions (PCR). Genotyping was performed directly on DNA from the PCR-positive tissue samples using 11 PCR restriction fragment length polymorphism markers (SAG1, 5′- and 3′-SAG2, alternative SAG2, SAG3, BTUB, GRA6, L358, PK1, c22–8, c29–2, and Apico). Results Of all samples, thirty-four were positive for the T. gondii B1 gene (2.06%, 95% CI: 1.86%–2.26%) from four cities, including 31 from NanYang city, one (PgXY 1) from Xinyang City, one (PgZZ 1) from Zhengzhou City and one (PgZK1) from Zhoukou City. The prevalence was found to be highest in piglets than in fattening pigs and sows. And the difference was statistically significant (P<0.01). The following 32 samples were genotyped with complete data: 13 hilar lymph node tissue samples, seven liver tissue samples, seven lung tissue samples, four spleen tissue samples, and one amniotic fluid sample. Only one genotype, belonging to ToxoDB Genotype #9, was identified. Conclusions This is the first large-scale survey molecularly characterizing T. gondii from pigs in Henan. The results of the present study revealed that T. gondii infection is present in swine in Henan and is a potential source of foodborne toxoplasmosis in the investigated areas. Implementation of effective control measures for T. gondii to reduce the chance of zoonotic toxoplasmosis spreading from pig farms may be warranted. The results show that the ToxoDB #9 genotype may be the dominant T. gondii lineage in mainland China. These findings strengthen the limited Chinese T. gondii epidemiology database

A hydrated amorphous iron oxide nanoparticle as active water oxidation catalyst

Developing efficient water oxidation catalysts (WOCs) with earth-abundant elements still remains a challenging task for artificial photosynthesis. Iron-based WOC is a promising candidate because it is economically cheap, little toxic and environmentally friendly. In this study, we found that the catalytic water oxidation activity on amorphous iron-based oxide/hydroxide (FeOx) can be decreased by an order of magnitude after the dehydration process at room temperature. Thermogravimetric analysis, XRD and Raman results indicated that the dehydration process of FeOx at room temperature causes the almost completely loss of water molecule with no bulk structural changes. Based on this finding, we prepared hydrated ultrasmall (ca. 2.2 nm) FeOx nanoparticles of amorphous feature, which turns out to be extremely active as WOC with turnover frequency (TOF) up to 9.3 s(-1) in the photocatalytic Ru(bpy)3(2+)-Na2S2O8 system. Our findings suggest that future design of active iron-based oxides as WOCs requires the consideration of their hydration status. (C) 2019, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved

ahydratedamorphousironoxidenanoparticleasactivewateroxidationcatalyst

由于传统化石燃料的不可再生性和使用过程中对环境的污染,近年通过太阳光驱动催化水分解制备氢气或CO2还原制备甲醇等高能化学燃料是人工光合作用制备太阳能燃料领域的研究重点.水的氧化反应是制备太阳能燃料的重要半反应,为质子或CO2的还原提供必需的质子和电子,开发基于非贵金属氧化物的高效水氧化催化剂是人工光合作用制备太阳能燃料的重要挑战之一.最近我们课题组的研究发现,无定形氧化钴作为水氧化催化剂时,其本征活性比结晶态的高出一个数量级.与氧化钴催化剂相比,铁基氧化物作为水氧化催化剂具有许多优点,比如成本低、环境友好、对动植物不产生生理毒性.基于此,本文探索了开发制备具有高催化活性的铁基氧化物作为水氧化催化剂.结果发现,氧化铁水氧化催化剂活性不但受其结晶度影响,还与其水合状态密切相关.水合氧化铁在进行室温真空干燥脱水处理后,在Ru(bpy)3^2+-Na2S2O8光催化水氧化体系中,其催化水氧化活性降低了一个数量级.热重分析、XRD和拉曼测试等结果表明,室温下进行脱水处理后,氧化铁基本不含有水分子的信号,其体相结构没有发生显著的变化.XRD和拉曼结果表明,催化水氧化测试后回收的氧化铁催化剂结构没有发生改变,表明该水合状态的氧化铁是水氧化过程中真实的催化剂成分,并不是充当前驱体的角色.基于此,我们进一步制备了尺寸较小且为水合状态的无定形氧化铁纳米粒子,后者在Ru(bpy)3^2+-Na2S2O8光催化水氧化体系中显示出极高的催化活性,TOF值高达9.3 s^-1,基于产生的氧气分子计算的光催化量子效率达到67%.该尺寸较小的水合状态氧化铁纳米粒子还可以有效地负载在SiO2表面进行催化水氧化反应,循环测试结果表明,负载的水合状态氧化铁纳米粒子连续进行三个催化水氧化循环测试,其活性未明显衰减,显示了较高的稳定性.该结果表明,未来设计铁基氧化物作为高活性的水氧化催化剂时,需要特别考虑其水合状态

The efficacy of radiofrequency hyperthermia combined with chemotherapy in the treatment of advanced ovarian cancer

This study investigated the effect of radiofrequency hyperthermia combined with chemotherapy in the treatment of advanced ovarian cancer