镁电池的研究进展

本文对比了镁电池与锂电池、锌锰电池的性能，综述了镁锰干电池、镁二次电池、镁海水电池和镁空气电池的结构、优缺点、目前应用以及存在的问题，并指出镁的氧化性、镁离子的负差效应、镁的抗蠕变性能低以及易发生自腐蚀反应会影响到镁电池的性能，解决这些问题是今后各种镁电池的主要研究方向和内容。     

近年国外镁工业动态

近年国外镁工业动态郑州轻金属研究院柯淑琴近两年由于西方国家经济的复苏，对镁需求的增加，使正处于减产状态下的镁市场缺镁，便从独联体和中国进口镁及动用库存来满足对镁的需求，这促进了中国镁工业的飞速发展，同时也迫使西方国家复产、扩产和建新厂，来保持供需平衡...     

我国镁合金加工的现状及未来发展

本文综述了中国镁工业和镁加工业的现状，介绍了国外发达国家及地区当前镁加工业的发展状况，分析了国内发展镁加工业的潜在优势。     

铁水镁脱硫工艺技术调研

本文简述了镁行业的发展，钢铁行业采用镁脱硫的条件，镁与其它脱硫剂的比较。镁的分类，镁脱硫的工艺方法及镁脱硫的优点；主要对镁脱硫进行了理论分析，综述了国内外钢铁厂采用镁脱硫进行生产的实践。     

我国的镁工业必须有序发展

在国际金属市场上，镁的价格一直相对稳定，而从１９９３年起受世界经济复苏大气候影响，人格直线上升同时也刺激了我国镁的生产，三年内使我国从镁的进口国一跃成为世界第二大镁的出口国，本文从国内外镁的生产和消费分析，措出这个形势是我国镁工业发展的契机，但由于当前的技术原因和国内消耗有限，镁生产一哄面起会造成资源浪费，还要担受国际市场变幼的风险，不宜大上镁的生产工业。为使我国镁工业健康发展，国家有关管理部门应     

关于中国镁工业的思考

概述了镁及镁合金的特性和应用，综述了中国镁工业的发展状况，对如何发展我国镁工业提出了建议。     

镁基铁水脱硫工艺技术分析

论述了镁基铁水脱硫的工艺和反应原理，分析了镁基铁水脱硫过程中的影响因素，阐述了镁基脱硫剂的工艺计算方法。     

安钢转炉用镁碳砖的质量及损毁机理研究

基于安钢转炉使用的几种镁碳砖理化性能及抗渣侵蚀能力的检测结果，对镁碳砖的质量进行了评价，并借助于显微镜和电子探针对转炉使用后的镁碳砖结构和物相组成进行了观察分析，讨论了转炉镁碳砖炉衬的损毁机理，提出了减少蚀损的建议。     

选冶产品中钙镁的物相分析方法

建立了选冶产品中钙和镁物相的分析方法，可同时测定选冶产品中钙、镁、硫酸盐相；钙、镁氧化物相及其他钙镁相；分相后经苯甲酸铵─铜试剂沉淀分离，取分样进行钙镁连续络合滴定；实现了对钙和镁物相的连续分相测定并获满意结果。     

俄罗斯用光卤石电解生产金属镁

俄罗斯镁生产工艺技术是从光卤石(含氯化钾／氯化镁)中直接进行电解来生产金属镁，在全世界有4家镁厂采用了这种生产工艺技术，他们是俄罗斯素里卡姆斯克镁厂(Sol：KaTnsk)，阿维斯玛镁厂(Avisma)，以色列死海镁厂和哈萨克一家小型镁厂。这4家镁厂产能达到8．5万t／a，其中以色列死海镁厂产能达到3．5万t／a。     

Magnesium homeostasis and renal magnesium handling

Magnesium is essentially an intracellular cation, which makes it difficult to evaluate magnesium status. About 1% of total body magnesium is present in serum and interstitial body fluid and only about 1% of the intracellular magnesium is in the free form, Mg2+. Recent studies show that this small fraction of free Mg2+ rapidly changes with the extracellular magnesium. These free Mg2+ levels are carefully controlled within the cell and total cellular magnesium content are maintained at the expense of extracellular fluid and bone magnesium levels. Regulation of magnesium balance is met between intestinal absorption and renal excretion. The excretory side of magnesium balance involves appropriate changes in renal magnesium handling. Present evidence indicates that renal handling of magnesium normally is a filtration-reabsorption process; magnesium is filtered at the glomerulus and reabsorbed along the various segments making up the renal nephron. About 80% of total serum magnesium (0.7-1 mmol/l) is filtered at the glomerular membrane. Of the ultrafilterable magnesium (0.6-0.8 mmol/l) 20-25% is reabsorbed by the proximal tubule, including the convoluted and straight portions. Some 50-60% of the filtered magnesium is reabsorbed in the loop of Henle, specifically by thick ascending limb cells. The terminal nephron segments, including the distal convoluted tubule and collecting ducts, reabsorb only a small portion of the filtered magnesium (about 5-10%). The loop of Henle plays the major role in determining magnesium reabsorption and urinary magnesium excretion. The loop of Henle also is the segment in which the major regulatory factors act to maintain magnesium balance.(ABSTRACT TRUNCATED AT 250 WORDS)     

The nitric oxide pathway in pre-eclampsia: pathophysiological implications

Ageing constitutes a risk factor for magnesium deficit. Primary magnesium deficit originates from two etiological mechanisms: deficiency and depletion. Primary magnesium deficiency is due to insufficient magnesium intake. Dietary amounts of magnesium are marginal in the whole population whatever the age. Nutritional deficiencies are more pronounced in institutionalized than in free-living ageing groups. Primary magnesium depletion is due to dysregulation of factors controlling magnesium status: intestinal magnesium hypoabsorption, reduced magnesium bone uptake and mobilisation, sometimes urinary leakage, hyperadrenoglucocorticism by decreased adaptability to stress, insulin-resistance and adrenergic hyporeceptivity. Secondary magnesium deficit in ageing largely results from various pathologies and treatments common to elderly persons: i.e. non insulin dependent diabetes mellitus and use of hypermagnesuric diuretics. Magnesium deficit may participate in the clinical pattern of ageing: mainly neuromuscular, cardiovascular and renal symptomatologies. The consequences of hyperadrenoglucocorticism--whose non response to dexamethasone suppression test appears the simplest marker--may concern immunosuppression, muscle atrophy, centralization of fat mass, osteoporosis, hyperglycemia, hyperlipidemia, atherosclerosis, disturbances in mood and mental performances through accelerated hippocampal ageing particularly. Treatment of magnesium deficiency requires simple oral physiological magnesium supplementation. Treatment of the different types of magnesium depletion leads to a more or less specific control of pathophysiological disturbances of the required magnesium substrate. Open and double blind studies on the effects of the treatments of magnesium deficiency and of magnesium depletions in geriatic populations are too scarce. Further study is necessary to assess the accurate place of magnesium deficit in the physiopathology of ageing.     

镁渣资源化研究新进展

镁渣为镁工业硅热还原法生产金属镁产生的废渣,随着我国镁工业的迅猛发展,如何改变镁渣传统的堆积、掩埋的处理方式,将镁渣资源化、再利用已成为一个亟需解决的问题。基于此介绍了镁渣的生成机理,分析了目前国内外镁渣的研究现状及存在的问题,并对镁渣未来的研究方向进行了展望。     

CaO在镁基铁水炉外脱硫工艺中的作用

在镁基铁水炉外脱硫工艺中,单喷镁粉时镁的利用率较低,特别是脱硫目标值较低时,Mg的溶解损失较大,且扒渣比较困难。根据对CaO在镁基铁水炉外脱硫工艺中作用的分析,采用CaO-Mg复合喷吹工艺,特别是铁水目标硫含量较低时,可以减少铁水脱硫所需的镁粉量,降低运行成本。铁水脱硫过程中加入CaO,还有利于改善脱硫粉剂的喷吹效果,并利于扒渣。在CaO-Mg复合喷吹法铁水脱硫工艺中,应根据不同反应阶段的特点,改变CaO和镁粉的喷吹速率。     

金属镁粒铁水脱硫过程动力学

通过对金属镁粒铁水脱硫过程动力学的研究发现,金属镁粒的粒径越大,镁粒气化后的气泡在铁液中的停留时间和平均上浮速率就越大,铁液中镁脱硫反应的传质系数减小;上浮速率及停留时间与铁液温度几乎没有关系,但传质系数随温度的增加而增加;在一定的铁液深度和铁液硫含量时,金属镁粒铁水脱硫时镁的利用率随镁粒的粒径增加而减小;温度对镁的利用率的影响在镁粒粒径小时比粒径大时要大,在铁液硫含量小时比硫含量大时影响要大;就脱硫过程动力学而言,温度越高越有利于铁液中镁的脱硫反应,这与热力学结论相反;铁液温度为1573 K,铁液中的w([S])为0.06%,铁水包的深度为3 m,在镁粒半径范围为(3～16)×10-4 m时,理论计算镁脱硫时镁的平均利用率为83.1%,与宣化钢铁公司生产得到的数据进行了对比,得到很好的吻合.     

Product activation of human erythrocyte AMP deaminase

Maternal magnesium requirements increase during pregnancy because of the synthesis of new tissue--both fetal and maternal. Magnesium takes part in almost 300 enzymatic reactions in the human body and regulates membrane permeability and protein bio-synthesis by promoting initiation and dissociation factors. The absorption velocity of magnesium differs from one tissue to another in animal experiments. It is highest in the liver, kidney, heart and is low in skeletal muscle, the brain and erythrocytes. It obeys and follows the Michaelis-Menten Kinetic law. 15 mmol of magnesium is consumed daily depending on the types of food takenin. The main sources of magnesium are vegetables and meats. Many Nigerian women are not able to afford enough of these. The amount of magnesium reabsorbed depends on the magnesium intake and not on magnesium needed which is about 10-40% of the intake. In this study, we examined the short-term effect of magnesium asphat HCL (614.18 mgMG), magnesium diasporal (magnesium citrate 610 mg + magnesium laevalitat 30 mg = 100 mg magnesium = 8.2 mval), ferrous gluconate (300 mg) plus folic acid and chemiron, a new combination hematinic agent (ferrous fumarate 300 mg, folic acid 5 mg, vitamin B12 10 mg, vitamin C 25 mg, magnesium sulfate 0.3 mg and zinc sulfate 0.3 mg) on plasma magnesium concentration during early pregnancy in Nigerian women. Significant increases of plasma magnesium concentrations were found in these groups (magnesium asphat HCL, 0.83 +/- 0.12 to 0.96 +/- 0.14 mmol/l, magnesium diasporal 0.843 +/- 0.14 to 0.891 +/- 0.14 mmol/l and chemiron 0.848 +/- to 0.866 +/- 0.16 mmol/l after five days. The ferrous gluconate and folic acid treated group showed no significant changes. This study shows that a chemiron supplement leads to increased magnesium plasma levels whereas ferrous gluconate and folic acid do not. These results suggest that the low level of magnesium is a normal physiological adjustment of pregnancy and that iron supplementation does not influence this unless magnesium salt is given.     

Recycling of Magnesium Alloy Employing Refining and Solid Oxide Membrane (SOM) Electrolysis

Pure magnesium was recycled from partially oxidized 50.5 wt pct Mg-Al scrap alloy and AZ91 Mg alloy (9 wt pct Al, 1 wt pct Zn). Refining experiments were performed using a eutectic mixture of MgF₂-CaF₂ molten salt (flux). During the experiments, potentiodynamic scans were performed to determine the electrorefining potentials for magnesium dissolution and magnesium bubble nucleation in the flux. The measured electrorefining potential for magnesium bubble nucleation increased over time as the magnesium content inside the magnesium alloy decreased. Potentiostatic holds and electrochemical impedance spectroscopy were employed to measure the electronic and ionic resistances of the flux. The electronic resistivity of the flux varied inversely with the magnesium solubility. Up to 100 pct of the magnesium was refined from the Mg-Al scrap alloy by dissolving magnesium and its oxide into the flux followed by argon-assisted evaporation of dissolved magnesium and subsequently condensing the magnesium vapor. Solid oxide membrane electrolysis was also employed in the system to enable additional magnesium recovery from magnesium oxide in the partially oxidized Mg-Al scrap. In an experiment employing AZ91 Mg alloy, only the refining step was carried out. The calculated refining yield of magnesium from the AZ91 alloy was near 100 pct.     

Magnesium, calcium and zinc levels of maternal and fetal tissues in magnesium deficient rats

The interaction of magnesium with two other mineral elements, calcium and zinc, was studied in maternal tissues and fetuses of pregnant rats fed a magnesium deficient diet throughout gestation. Reduction in maternal femur magnesium and a trend for increased kidney calcium reflected the dietary magnesium deficiency. In fetuses, however, total magnesium content was reduced and , in addition, fetal zinc content was also lower than normal in the group most severly deficient in magnesium. The possible interpretation of this magnesium-zinc interaction is discussed.     

高纯金属镁比较-气体容量法测定炼钢辅料中金属镁或金属钙

提出了一种采用高纯金属镁比较-气体容量法测定炼钢辅料钝化镁脱硫剂中金属镁和钙铁包芯线中金属钙的方法。分别采用稀盐酸和氯化铵溶液溶解钝化镁脱硫剂和钙铁包芯线样品, 使样品中的金属镁或金属钙与溶样试剂中的氢离子发生反应, 置换出等当量的氢气, 用自制的排水法量气体体积装置测定样品的产氢气体积;在相同温度和压力下, 采用溶样试剂溶解高纯金属镁标样, 测定其产氢气体积;根据气体状态方程, 通过比较法计算出钝化镁脱硫剂中金属镁或钙铁包芯线中金属钙的含量。方法应用于钝化镁脱硫剂样品中金属镁的测定, 结果与碘-乙醇提取-EDTA络合滴定法一致, 相对标准偏差(RSD, n=6)小于0.3%;方法应用于钙铁包芯线样品中金属钙的测定, RSD(n=6)小于1.8%, 回收率为98%~99%。     

Abnormal renal magnesium handling

The normal fractional urinary excretion of filtered magnesium is about 5%. In magnesium deficiency in man, the kidneys can normally reduce the 24-hour urinary magnesium excretion to less than 1 mmol (24 mg) via unknown mechanisms, and initially without a fall in plasma magnesium concentration. Renal magnesium wasting may be defined as a urinary excretion greater than 1 mmol/day in the presence of hypomagnesemia (plasma magnesium < 0.7 mmol/l). Congenital renal magnesium wasting occurs in several syndromes including Bartter's syndrome in which it is associated with hypercalciuria, and the defect may be in the thick ascending limb of Henle's loop, and Gitelman's syndrome in which there is hypocalciuria, and the defect may be in the distal convoluted tubule. Other causes of renal magnesium wasting include diabetes mellitus, hypercalcemia and diuretics. Magnesium wasting may also result from various toxicities including those of cis-platinum, in which the biochemical features resemble Gitelman's syndrome, and those of aminoglycosides, pentamidine and cyclosporin. Calcitriol deficiency may also contribute to renal magnesium wasting in some circumstances. Mild hypermagnesemia may occur in familial hypocalciuric hypercalcemia and may reflect abnormal sensitivity of the loop of Henle to calcium and magnesium ions. By contrast, the hypermagnesemia that occurs in chronic renal failure results from the reduced glomerular filtration of magnesium.