从废镍催化剂中提取镍,生产硫酸镍

介绍了如何从废镍催化剂中提取镍，减少环境污染，降低硫酸镍的制造成本。     

用电解镍生产水碎镍的研究与实践

本文介绍了电解镍经中频感应电炉熔化,生产水碎镍粒的工艺,并对熔体温度、溢流高度、水温、水压、水量、还原剂等影响因素进行了探讨。     

镍矿石中镍的物相分析

本分析方法分析硫酸镍相中的镍,氧化镍相中的镍,硫化镍相中的镍和硅酸镍相中的镍,方法基于醋酸钠和亚硫酸钠浸取硫酸镍,用柠檬酸浸取氧化镍,再用饱和溴水浸取硫化镍和硫酸镍,最后残渣中测定硅酸镍。     

Clinical biochemistry of pregnancy

Major adaptations in maternal physiology and metabolism are required for successful pregnancy outcome. Hormonal changes initiated even before conception significantly alter maternal biochemistry early in pregnancy. Steroid hormones, peptide hormones, and prostaglandins interact to expand blood and plasma volume and modulate the maternal capacity to supply energy and nutrients to the fetoplacental unit. As gestation progresses, reference ranges for the concentration of many biochemical parameters change significantly from those found in the nonpregnant state. Gestation-specific reference ranges are essential for correct interpretation of tests used in screening, diagnosis, and monitoring during pregnancy. The use of clinical laboratory tests in the management of high-risk pregnancy are discussed from the perspective of testing before conception and during pregnancy.     

Endocrine biochemistry of puberty

Puberty corresponds to the development of gonads and secondary sexual characteristics, and on a biological point of view, to the functional maturation of the gonadal axis. Puberty begins at the age of 11.5 to 12 years in males and 10.5 to 11 years in females. Depending on secondary sexual characteristics, particularly pubic pilosity, puberty is classified in five stages (Tanner's stages). During puberty growth velocity increases in response to gonadal steroid secretion. From a biochemical point of view, three steps are involved in the development of the hypothalamo-hypophysogonadal axis: 1. nocturnal hypothalamic GnRH secretion increases and becomes pulsatile (a peak every 60 to 90 min); 2. the pituitary gonadotrophins FSH and LH follow the same pattern of secretion as GnRH; increase of GnRH and FSH/LH secretion is due to a decrease in hypothalamo-hypophysal sensitivity to the negative feed back exerted by circulating gonadal steroids; 3. secretion of estradiol in females and testosterone in males increases, as a consequence of pituitary stimulation. Hormonal exploration of puberty is mainly based on the measurement of FSH-LH and testosterone or estradiol. SDHA is also measured to investigate adrenal androgen secretion, which increases three or four years before puberty; this is related to the maturation of adrenal androgenic function (adrenarche). Dynamic tests are used to evaluate the biological stage of puberty (LH-RH test) and to measure the functional capacity of the testes. Pubertal abnormalities can theoretically be divided into precocious and delayed puberty. In the former, clinical and biological characteristics are used to define: dissociated puberties, central precocious puberty and peripheral precocious puberty. In the latter, hypogonadism has either a central origin (hypogonadotropic hypogonadism) or peripheral origin (hypergonadotropic hypogonadism).     

粗硫酸镍溶液直接萃取镍的工艺研究

使用新型萃取剂HBL110从粗硫酸镍溶液中直接萃取镍。结果表明,萃取的较优条件为：萃取剂皂化率60%、萃取相比V_O：V_A=2：1、料液起始pH=2.2、萃取时间5 min,经5级逆流萃取,镍萃取率为98.63%,铁、钴、锌、钙、镁的萃取分别为10.41%、22.86%、8.42%、1.75%、1.38%。有机相经酸洗后反萃,反萃的较优条件为：反萃剂H₂SO₄浓度1.0 mol/L、反萃相比V_O：V_A=4：1、反萃时间5 min,该条件下进行4级逆流反萃,镍的反萃率为98.85%,反萃液镍浓度为31.11 g/L,且反萃液杂质含量低。     

高镍锌白铜的性能研究

采用水平连铸－拉拔－轧制生产工艺锌白铜异材，对高镍锌白铜的金相组织，机械性能及退火工艺进行了研究。研究表明α单相高镍锌白铜具有优良的机械性能，适宜冷热加工，退火温度为７００－７５０℃，颜色为银白色。该材料完全能满足高档眼镜用异形材料的要求。     

PET: brain tumor biochemistry

Most mechanisms of drugs which are used in brain tumor chemotherapy are well characterized: alkylation of DNA components (nitrosoureas), binding with tubulin protein resulting in metaphase arrest (vincristine), chromatid breaks and chromosome translocations (procarbazine), or inhibition of ribonucleotide reductase (hydroxyurea) [1]. These drugs exert their effects mainly during certain cell cycle phases of proliferating cells, particularly when DNA is synthesized. From this it can be assumed that the efficacy of these drugs depends on the fraction of proliferating cells. Thus it would be of great importance to estimate the proliferation rate of brain tumors which could guide chemotherapy in individual patients. Positron emission tomography (PET) measures quantitatively the in vivo tissue uptake of tracer substances. In tumors, the uptake appears to be altered in a characteristic way determined by biochemical properties of tumor tissue. Some aspects of brain tumor metabolism which are theoretically related to proliferation have been investigated with PET. In the following, the literature is reviewed with regard to: 1) tracer substances whose uptake has been thought to reflect tumor malignancy (11C-methionine, 18F-fluoro-deoxyglucose), and 2) tracers which theoretically could reflect mechanisms specifically related to DNA synthesis (11C-putrescine, ligands for peripheral benzodiazepine receptors).     

Extraction of Nickel from Oxidized Nickel Ores by Heap Leaching

Metallurgist - A characteristic feature of serpentine oxidized nickel ores (ONO) of the Serov deposit (≈ 1 wt.% Ni) is the increased content of iron and magnesium. The main nickel-containing...     

从高镍锍中选择性回收镍的试验研究

高镍锍-硫酸选择性浸出工艺包括常压浸出和加压浸出.通过浸出,Ni、Co转入溶液而Fe、Cu等杂质富集在浸出渣中.与镍同时浸出的钴用Cyanex272溶剂萃取分离或用黑镍去除,最终得到纯净的硫酸镍溶液,可用于生产硫酸镍或电积镍.     

The dark side of dioxygen biochemistry

The aim of this study was to evaluate the clinical function and long-term prognosis of overdentures retained by a small number of implants in the maxilla and mandible using one of two different attachment systems. Included in the study were all patients referred to specialty clinics in J?nk?ping and Link?ping, Sweden, during the treatment period who needed an overdenture and could be provided with a minimum number of two bilaterally-placed implants. Excluded were patients with bone-grafted jaws, irradiated cancer patients, heavy bruxers, and patients who had lost a fixed prosthesis because of implant losses. The patients were randomly assigned to receive one retentive system, either a round 2-mm-diameter bar with clips or ball attachments (Nobel Biocare). Eighteen overdentures were placed in maxillae and 32 in mandibles, supported by a total of 115 Br?nemark implants. Of the implants placed, 86.1% were continuously osseointegrated. The cumulative implant survival rates after 7 years of loading were 75.4% in the maxillae and 100% in the mandibles. There was no difference in implant survival rate between the attachment systems. Patients with implant losses were characterized by severely resorbed maxillary ridges and inferior bone quality, together with unfavorable loading circumstances such as short implants combined with long leverages. Complications and prosthetic adjustments were mostly resolved early and easily.     

从废镍催化剂中回收镍并生产硫酸镍

试验了从废镍催化剂中回收镍并生产硫酸镍。废镍催化剂用硫酸溶解并去除硅酸之后,通过碱析获得粗硫酸镍产品,再通过净化、二次碱析及结晶,获得纯度较高的NiSO4.7H2O产品。该方法可从废镍催化剂中充分回收镍资源,并对环境有利。     

镍及镍合金板带材生产线工艺及设备

介绍了镍及镍合金板带材生产线主要工艺参数和工艺装备。