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751.
论加强干部教育培训工作的对策和思考 总被引:1,自引:0,他引:1
针对干部教育培训工作目前存在的一些问题,论述了如何增强干部教育培训的实效性,给干部教育培训工作提出了新的更高的要求。 相似文献
752.
高晓彩 《西北大学学报(自然科学版)》1998,28(4):365-368
对宁强县某两乡(缺碘地区)7岁~14岁弱智(MentalRetardationMR)儿童及对照组儿童进行了神经运动功能检查,以查找该地区MR儿童的深层病因。结果表明,该地区MR儿童与正常儿童之间、该地区正常儿童与补碘后正常地区的儿童之间,在神经运动功能方面均存在显著性差异。进一步分析发现,这种神经运动功能损伤存在个体差异,即部分MR儿童在有智力落后的同时伴有神经运动功能障碍,而部分MR儿童仅表现为智力落后。因此提示,以碘缺乏为主的营养不足很可能是该地区MR儿童的致病因素之一。 相似文献
753.
文章就如何在中等职业类学校中“五笔”课程教学进行了初步探索,从5个方面论述了“五笔”课程的教学方法与手段,着重培养学生理论和实际相结合的能力。 相似文献
754.
针对干部教育培训工作目前存在的一些问题,论述了如何增强干部教育培训的实效性,给干部教育培训工作提出了新的更高的要求. 相似文献
755.
采用着色腐蚀法,借助电子探针定量分析了Si、Mn元素在球铁枝晶中的分布特征及其偏析行为,以及碳当量、壁厚对Si、Mn元素偏析行为的影响。结果表明:Si在枝晶中的偏析系数KSiS和分配系数KSi均大于1,而Mn的偏析系数KMnS和分配系数KMn均小于1;Si在奥氏体枝晶晶粒内分布具有一定的空间几何对称性,沿径向呈阶梯形分布特点;在Si平均含量不变和试样壁厚相同的情况下,随着碳当量的增大,Si、Mn元素在枝晶中的分配系数基本保持不变。 相似文献
756.
A process with potentially reduced environmental impacts and occupational hazards of lead-bearing zinc plant residue was studied to achieve a higher recovery of lead via a cost-effective and environmentally friendly process. This paper describes an optimization study on the leaching of lead from zinc leach residue using acidic calcium chloride aqueous solution. Six main process conditions, i.e., the solution pH value, stirring rate, concentration of CaCl2 aqueous solution, liquid-to-solid (L/S) ratio, leaching temperature, and leaching time, were investigated. The microstructure and components of the residue and tailing were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD). On the basis of experimental results, the optimum reaction conditions were determined to be a solution pH value of 1, a stirring rate of 500 r·min-1, a CaCl2 aqueous solution concentration of 400 g·L-1, a liquid-to-solid mass ratio of 7:1, a leaching temperature of 80℃, and a leaching time of 45 min. The leaching rate of lead under these conditions reached 93.79%, with an iron dissolution rate of 19.28%. Silica did not take part in the chemical reaction during the leaching process and was accumulated in the residue. 相似文献
757.
Thermodynamics and kinetics of alumina extraction from fly ash using an ammonium hydrogen sulfate roasting method
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A novel method was developed for extracting alumina (Al2O3) from fly ash using an ammonium hydrogen sulfate (NH4HSO4) roasting process, and the thermodynamics and kinetics of this method were investigated. The thermodynamic results were verified experimentally. Thermodynamic calculations show that mullite present in the fly ash can react with NH4HSO4 in the 298–723 K range. Process optimization reveals that the extraction rate can reach up to 90.95% when the fly ash reacts with NH4HSO4 at a 1:8 mole ratio of Al2O3/NH4HSO4 at 673 K for 60 min. Kinetic analysis indicates that the NH4HSO4 roasting process follows the shrinking unreacted core model, and inner diffusion through the product layer is the rate-controlling step. The activation energy is calculated to be 16.627 kJ/mol; and the kinetic equation can be expressed as 1 ? (2/3)α ? (1 ? α)2/3 = 0.0374t exp[?16627/(RT)], where α is the extraction rate and t is the roasting temperature. 相似文献
758.
为了改善大气环境,满足人民群众对良好的大气环境的需要,首先要对大气质量做出全面的合理的评价,考虑到物联网监测数据只能反映空气监测站点周围有限区域的大气质量情况,且利用公众感知情感分析大气质量在客观性上略有不足,为此,基于物联网监测数据与公众感知情感数据建立大气质量综合评价模型,以山东省为例对2016年12个月的大气质量做了综合评价.结果表明:山东省2016年的大气质量超半数月份里以中度污染为主,中度污染地区以及严重污染地区加起来占全省面积一半以上,这些地区多分布在山东省的中部、中东部以及南部,此外重度污染地区主要分布在东营市、滨州市的北部、青岛市以及潍坊市的南部地区,对此相关部门应该重点关注重度污染地区大气环境状况,切实解决环境问题,满足群众对优美大气环境的诉求. 相似文献
759.
Maize transformation via pollen tube pathway and the inheritance of transgene in progeny 总被引:2,自引:0,他引:2
The herbicide-resistant gene als was introduced into maize inbred line Qi319 through pollen-tube pathway. The inheritance of transgene was studied up to 33 generation. Transformation was performed by applying plasmid DNA carrying solution on the severed styles after self-pollination, or just prior to selfpoll/nation. After herbicide screening, PCR and Southern blot analysis, seventeen plants were confirmed positive in TO generation, and sixteen of them were self-bred to construct family to 33 progeny. Through PCR analysis and herbicide screening in offspring, four lines were confirmed following a 3 : 1 Mendelian segregation ratio. In other lines the numbers of positive plants were lower than expected. Therefore, it is necessary to select large population in progeny to produce stable inherited lines when transgene was delivered by pollen tube method. 相似文献
760.
Wang Qinghua 《高技术通讯(英文版)》2005,11(3):315-319
A new MAPK gene, ZmSIMK1 (Zea mays L. salt-induced mitogen-activated protein kinase 1), is isolatod from a maize eDNA library. The full-length ZmSIMK1 gene contains 1636 bp and an open reading frame of 1122 nucleotides capable of eneoding 373 amino acid polypeptides with a predicted molecular mass of 42.3 kda and pI of 6.01. The putative ZmSIMK1 protein contains all 11 conserved subdomains that are characteristics of serine/threonine protein kinases and the TEY motif, which is the putative phosphorylation site. Northern blot analysis shows that ZmSIMK1 is ubiquitously expressed in roots, stems, and leaves of maize seedlings and its mRNA accumulation is observed in maize seedlings treated with 30 mmol/L PEG-6000 and 137 mmol/L NaCl, but the expression of ZmSIMK1 is not significantly affected by 4℃ treatment. The expression vector pET-ZmSIMK1 is constructed by inserting the coding region of ZmSIMK1 eDNA into pET-42a(+), and transformed into E. coli strain BL21(DE3). A 77kda fusion protein is induced by the further culture at 37℃ after addition of 1 mmol/L IPTG. 相似文献