三价锰光度法快速测定铬镍锰高合金中高含量锰

在磷酸介质中，于220℃温度下，用高氯酸将二价锰氧化为三价锰，因三价锰离子的摩尔浓度系数远较七价锰离子的小，借此可做高含量锰的光度法分析。     

来冶铟系统技改设计思路浅述

介绍了来冶铟系统技改中用矾渣挥发、三段浸出、萃取提铟工艺替代原有的矾渣焙解、二段酸浸、萃取提铟工艺的设计思路，以实现投入少、改动小、收益大的目标。     

120 kt/a硫磺制酸水管锅炉改造为火管锅炉的技术总结

介绍FRS-12S-14.5/3.82-450型余热水管锅炉以较少的投资、较少的工程量、较短的施工周期改造成QF35/1050-14.2-3.82/450型火管锅炉,使热力系统满足了120kt/a硫磺制酸装置的工艺要求。改造后系统运行平稳,运行率提高,维护费用减少,生产成本降低,解决了水管锅炉因换热管束爆管导致锅炉腐蚀及烟气泄漏造成的环境污染等问题。     

浙江省硫酸工业进展

介绍近6年来浙江省的硫酸产能和产量及下游耗酸产业结构.浙江省2005年硫酸产量占全国总产量的3%,预计2006年产量将达到1 600 kt.建议缓建硫酸装置,积极发展耗酸行业,控制进口酸量,加强企业间的协调,以使浙江省的硫酸市场在新的供需形势下建立起新的平衡.     

建龙化工新建150 kt/a硫磺制酸装置的几个特点

为保证原有4 500 kW发电机组满负荷运行的蒸汽供给及考虑当地硫酸市场的需求,新建一套150 kt/a硫磺制酸装置.该装置以原120 kt/a硫磺制酸装置的设计为蓝本,进行一定改进.在装置设备的选型配套、熔硫工序的挖潜改造、严冬季节土建施工、风机噪音消除等方面采取了相应措施.装置开车以来运行良好,达到设计要求.     

The Effect of Formulation on Radioiodide Thyroid Uptake in the Hyperthyroid Cat

This investigation was designed to compare in vitro dissolution profiles from sodium iodide capsules with radioiodide thyroid uptake in hyperthyroid cats using sodium iodide capsules prepared with a formulation exhibiting a complete release of radioiodide (I-123) in vitro and a formulation with an incomplete release of radioiodide. In vitro dissolution profiles for I-123 sodium iodide capsules with two different formulations were determined using the USP XXIII dissolution test. The two formulations studied in vitro were sodium phosphate dibasic powder with 1% magnesium stearate and calcium phosphate dibasic powder with 3% magnesium stearate. By 20 min after initiation of the dissolution test, over 95% of the I-123 was released from capsules of sodium phosphate dibasic powder. The capsules of calcium phosphate dibasic powder reached 75% at 65 min, with no further release occurring thereafter. There was a statistically significant difference in the dissolution profiles of the two formulations. The thyroid uptake of I-123 from capsules exhibiting complete release and incomplete release of radioiodide was determined in hyperthyroid cats. At 4 hr, the mean percentage thyroid uptake value for sodium phosphate dibasic powder with 1% magnesium stearate (complete release formulation) was 12.0% compared to 9.4% for calcium phosphate dibasic powder with 3% magnesium stearate (incomplete release formulation); at 24 hr, the values were 34.4% compared to 23.7%. The data suggest that the incomplete dissolution profile observed in vitro may correlate with a reduction in the bioavailability of the radioiodide in vivo. However, using the Wilcoxon signed rank test, statistically significant differences did not occur between the complete release formulation and incomplete release formulation at either 4 hr or 24 hr (p >. 05). The results of the in vivo study with five hyperthyroid cats were not conclusive due to the variability in response between individual cats.     

地下煤制气制取液化天然气和液氢工艺研究

目的脱除地下煤制气中的酸气,将地下煤制气中的CH₄和H₂分离出来并液化。 方法对常见的分离方法进行对比,确定采用低温精馏法对煤制气进行脱酸气、分离CH₄和H₂并液化。根据低温精馏法的原理,设计了一种全新的地下煤制气脱酸气、分离CH₄和H₂并液化的工艺流程,该工艺主要由两个精馏塔、一个两相分离器和三级氦膨胀制冷系统组成。同时利用HYSYS软件对其进行模拟分析,确定最优参数。 结果该工艺可以将地下煤制气中CO₂的摩尔分数脱除到0,H₂S的摩尔分数脱除到3.65×10-14,满足处理要求。同时可以实现CH₄回收率为99.97%,加压液化天然气(PLNG)的摩尔分数为99.97%,H₂的回收率为98.30%,液氢(LH₂)的摩尔分数为99.99%。 结论该工艺可以有效利用地下煤制气制取PLNG和LH₂,且所需能耗较传统工艺能耗降低了11.64％,具有较高的经济效益。      

Roles of the Unsaturated Fatty Acid Docosahexaenoic Acid in the Central Nervous System: Molecular and Cellular Insights

Fatty acids (FAs) are essential components of the central nervous system (CNS), where they exert multiple roles in health and disease. Among the FAs, docosahexaenoic acid (DHA) has been widely recognized as a key molecule for neuronal function and cell signaling. Despite its relevance, the molecular pathways underlying the beneficial effects of DHA on the cells of the CNS are still unclear. Here, we summarize and discuss the molecular mechanisms underlying the actions of DHA in neural cells with a special focus on processes of survival, morphological development, and synaptic maturation. In addition, we examine the evidence supporting a potential therapeutic role of DHA against CNS tumor diseases and tumorigenesis. The current results suggest that DHA exerts its actions on neural cells mainly through the modulation of signaling cascades involving the activation of diverse types of receptors. In addition, we found evidence connecting brain DHA and ω-3 PUFA levels with CNS diseases, such as depression, autism spectrum disorders, obesity, and neurodegenerative diseases. In the context of cancer, the existing data have shown that DHA exerts positive actions as a coadjuvant in antitumoral therapy. Although many questions in the field remain only partially resolved, we hope that future research may soon define specific pathways and receptor systems involved in the beneficial effects of DHA in cells of the CNS, opening new avenues for innovative therapeutic strategies for CNS diseases.     

The Cytoskeletal Protein Zyxin Inhibits Retinoic Acid Signaling by Destabilizing the Maternal mRNA of the RXRγ Nuclear Receptor

Zyxin is an LIM-domain-containing protein that regulates the assembly of F-actin filaments in cell contacts. Additionally, as a result of mechanical stress, Zyxin can enter nuclei and regulate gene expression. Previously, we found that Zyxin could affect mRNA stability of the maternally derived stemness factors of Pou5f3 family in Xenopus laevis embryos through binding to Y-box factor1. In the present work, we demonstrate that Zyxin can also affect mRNA stability of the maternally derived retinoid receptor Rxrγ through the same mechanism. Moreover, we confirmed the functional link between Zyxin and Rxrγ-dependent gene expression. As a result, Zyxin appears to play an essential role in the regulation of the retinoic acid signal pathway during early embryonic development. Besides, our research indicates that the mechanism based on the mRNA destabilization by Zyxin may take part in the control of the expression of a fairly wide range of maternal genes.