高钙高铬低品位钒渣直接焙烧硫酸浸出提钒

钒渣是含钒钛磁铁矿冶炼的副产物,既是一种有潜力的有效提钒提铬原料,也是中国提钒最主要的原料之一。目前主要采用浸出方法提取渣中的钒,而含铬的有毒溶液提取钒后不能妥善处理,对人类、动物和环境都有潜在的威胁。此外,由于钒和铬在溶液中的化学性质相似,很难完全分离。基于此,研究了钙化焙烧—硫酸浸出工艺从钒渣中提取钒,而铬基本不被浸出留在渣中,考察了不同焙烧条件和浸出条件对钒渣中钒、铬、钙提取的影响。结果表明：钒渣中富含铁和硅元素,其中钒主要以三价离子状态存在于钒铁尖晶石（FeV2O4）中。钒渣的主要矿物组成还包括橄榄石相（Fe2SiO4）、硅酸盐相以及辉石相（Ca（Mg,Al,Fe)Si2O6）,这些成分共同构成了钒渣的矿物多样性。钒渣在n(CaO)/n(V2O5)＝1.25、钒渣粒度75 μm、950 ℃焙烧3 h,然后在70 ℃下用20%硫酸溶液浸出3 h,钒浸出率可达88.99%,铬、钙基本不浸出,钒渣杂质脱除效果较好。实现了从高铬钒渣（HCVS）中高效提取钒,浸出渣可作为提取铬的新原料,为钒钛磁铁矿中有价金属的综合利用提供了一条新途径。     

钒渣钙化焙烧熟料的浸出过程

The process of acid leaching of calcification roasted vanadium slag was studied. The effects of process parameters variation on phase of the vanadium leaching residue, leaching rate of vanadium and the reason of vanadium loss were analyzed. The results showed that the main phase of vanadium leaching residue was insoluble in acid of dense solid solution R2O3 and Fe2TiO5, which was also mixed with silicate pyroxene phase and small amount of vanadate phase. The vanadium leaching rate first increased and then decreased with raising the roasting temperature, roasting time and the CaO/V2O5 mass ratio. Silicate species and its effect on vanadate, spinel oxidation incomplete, vanadium and vanadium bronze solid solution in of R2O3, and the difference of best leaching acidity of Ca3V2O8, Ca2V2O7 and CaV2O6 were the causes of vanadium loss.     

Vascular calcification: Inducers and inhibitors

Unlike the traditional beliefs, there are mounting evidences suggesting that ectopic mineral depositions, including vascular calcification are mostly active processes, many times resembling that of the bone mineralization. Numbers of agents are involved in the differentiation of certain subpopulation of smooth muscle cells (SMCs) into the osteoblast-like entity, and the activation and initiation of extracellular matrix ossification process. On the other hand, there are factors as well, that prevent such differentiation and ectopic calcium phosphate formation. In normal physiological environments, activities of such procalcific and anticalcific regulatory factors are in harmony, prohibiting abnormal calcification from occurring. However, in certain pathophysiological conditions, such as atherosclerosis, chronic kidney disease (CKD), and diabetes, such balances are altered, resulting in abnormal ectopic mineral deposition. Understanding the factors that regulate the formation and inhibition of ectopic mineral formation would be beneficial in the development of tissue engineering strategies for prevention and/or treatment of such soft-tissue calcification. Current review focuses on the factors that seem to be clinically relevant and/or could be useful in developing future tissue regeneration strategies. Clinical utilities and implications of such factors are also discussed.     

cystatin C与冠状动脉钙化的相关性研究

目的 探讨胱抑素C（Cys C）与冠状动脉钙化的相关性。方法 选择2014年5月至2015年2月在青岛市市立医院就诊,有胸痛、胸闷症状,有中度心血管风险,既往无冠心病病史的患者,共201例,检测Cys C等生化指标,行冠脉CT检查。按Cys C是否升高分为两组,Cys C≤0.95组121例,Cys C＞0.95组80例。比较两组临床及生化指标是否有统计学意义,并进一步分析Cys C与冠状动脉钙化及冠脉多支病变的关系。结果 与Cys C≤0.95组相比,Cys C升高组Cr（P=0.002）、BNP（P=0.003）、CRP（P=0.03）水平明显升高,钙化程度（P＜0.01）及多支病变（P＜0.005）发生率显著升高;Cys C水平与冠状动脉钙化独立相关（OR=0.319,95%CI：0.265-0.467,P＜0．01）,Cys C水平与多支病变独立相关（OR=9.863,95%CI：3.157-217.571,P＜0.01）。结论 Cys C与冠状动脉钙化及冠脉多支病变存在密切的关联。     

磷酸盐阻断废纸制浆废水厌氧污泥钙化的应用研究

利用废水处理营养剂磷酸盐阻断碳酸钙结晶,探讨了磷酸盐对碳酸钙的晶格畸变及表层剥离作用,并对磷酸盐阻断厌氧反应器钙截留可行性进行了生产性验证试验。结果表明,向预酸化池中补充磷酸盐能够有效阻断厌氧反应器内污泥钙化,将钙截留率从38%降至8%以下;基于磷酸盐的污泥钙化阻断方法,通过调整磷酸盐投加方案可避免钙化污泥置换、碱化沉淀除钙引入非必须化学品或破坏污泥结构的弊端,为废纸制浆企业提供了技术可行、经济可控的解决方案。     

机械活化强化钒渣钙化提钒工艺

针对转炉钒渣钙化焙烧酸浸工艺中存在的钒转浸率低的问题,采用高能球磨对钒渣进行活化预处理,以期强化其提钒效果。采用激光粒度分析仪、BET比表面积测定仪和XRD对活化前后钒渣进行了粒度、比表面积及物相结构分析;采用浸出实验研究了机械活化对钙化焙烧和浸出的影响规律。结果表明：机械活化法增大了钒渣的比表面积,增加了晶格畸变与微观应力,使含钒物相充分解离,由此可改善钒渣钙化焙烧的动力学条件。在浸出20 min条件下,机械活化80 min可将钒浸出率提高10%,最佳焙烧温度降低100 ℃。     

钙化焙烧-酸浸提钒过程中含钒物相结构及其演变规律研究

对钒渣、熟料和残渣中含钒物相微观结构、形貌以及钒元素走向进行了分析, 考察了钙化焙烧-酸浸提钒过程中含钒物相结构及其演变规律。结果表明: 钙化焙烧过程中钒尖晶石由初始光滑致密的多边形逐渐氧化成多孔状态, 直至最后生成凹凸不平的“圆粒状”氧化铁和“短柱状”铁板钛矿, 钒元素也由最初富集在钒尖晶石中逐渐向钒酸钙、氧化铁、铁板钛矿和硅酸盐中转移; 酸浸过程中熟料中凹凸不平的含钒氧化物(氧化铁、铁板钛矿和钒酸钙)逐渐变为“镂空状”铁板钛矿相, 大部分钒元素被硫酸浸出, 残留的钒元素主要赋存于氧化铁、铁板钛矿和硅酸钙中。     

A Review of the Effect of Diet on Cardiovascular Calcification

Cardiovascular (CV) calcification is known as sub-clinical atherosclerosis and is recognised as a predictor of CV events and mortality. As yet there is no treatment for CV calcification and conventional CV risk factors are not consistently correlated, leaving clinicians uncertain as to optimum management for these patients. For this reason, a review of studies investigating diet and serum levels of macro- and micronutrients was carried out. Although there were few human studies of macronutrients, nevertheless transfats and simple sugars should be avoided, while long chain ω-3 fats from oily fish may be protective. Among the micronutrients, an intake of 800 μg/day calcium was beneficial in those without renal disease or hyperparathyroidism, while inorganic phosphorus from food preservatives and colas may induce calcification. A high intake of magnesium (≥380 mg/day) and phylloquinone (500 μg/day) proved protective, as did a serum 25(OH)D concentration of ≥75 nmol/L. Although oxidative damage appears to be a cause of CV calcification, the antioxidant vitamins proved to be largely ineffective, while supplementation of α-tocopherol may induce calcification. Nevertheless other antioxidant compounds (epigallocatechin gallate from green tea and resveratrol from red wine) were protective. Finally, a homocysteine concentration >12 µmol/L was predictive of CV calcification, although a plasma folate concentration of >39.4 nmol/L could both lower homocysteine and protect against calcification. In terms of a dietary programme, these recommendations indicate avoiding sugar and the transfats and preservatives found in processed foods and drinks and adopting a diet high in oily fish and vegetables. The micronutrients magnesium and vitamin K may be worthy of further investigation as a treatment option for CV calcification.     

Effect of sevelamer on aortic pulse wave velocity in patients on hemodialysis: a prospective observational study

Aortic stiffening and aortic calcification are risk factors for cardiovascular events in hemodialysis (HD) patients, and these 2 risk factors are interrelated. Sevelamer decreases aortic calcification but its effect on aortic stiffness has not been investigated previously. Thirteen HD patients commencing sevelamer treatment and 13 matched controls were followed for 11 months. Aortic pulse wave velocity (PWV), augmentation index (AIx), and levels of inhibitors of vascular calcification (fetuin-A, matrix-GLA-protein, osteoprotegerin/RANKL) were measured at baseline and at the end of follow-up, and the differences between the groups were compared. Determinants of the changes in PWV during follow-up were assessed by multivariate linear regression. At baseline, PWV was 9.93 (2.10) m/s in sevelamer-treated patients and 9.20 (2.84) m/s in control patients (p=0.464). By the end of follow-up, PWV decreased by 0.83 (2.3) m/s in sevelamer-treated patients while it increased by 0.93 (1.88) m/s in controls (p=0.042). The direction of changes in AIx were similar, but not statistically significant. There were no significant differences in the levels of inhibitors of calcification either at baseline or during follow-up. In multivariate linear regression sevelamer treatment, diabetes, heart rate, and C-reactive protein were related to the change in PWV. These data suggest that sevelamer treatment is associated with an improvement in aortic stiffness in HD patients, but it does not seem to affect serum levels of inhibitors of vascular calcification.     

钙化改性研制高硬度氧化蜡

以石蜡和聚乙烯蜡为主要原料,进行催化氧化反应,制得氧化蜡,然后对其进行钙化改性,得到高硬度的改性蜡。在钙化反应温度120℃,反应时间为4h条件下,考察了氢氧化钙用量对改性蜡性能的影响。结果表明,当氢氧钙用量为3．0％时,所得改性蜡的硬度等性质与天然硬蜡（巴西棕榈蜡）的性质接近,酸值为3．20mgKOH／g,皂化值为78．83mgKOH／g,针入度为1．7（0．1mm）,滴熔点为86．9℃。