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1.
通过大量的调查研究,查清了电磁站内渗漏水的缺陷,提出了解决方案和具体操作方法,改变了原定的搬迁方案,不仅彻底地消除了缺陷,还节约了大修费,缩短了工期,为生产创了可观的效益。  相似文献   

2.
承钢“八五”期间坚持“科技是第一生产力”的思想,紧紧依靠技术进步,狠抓节能降耗,增产增收,投资7亿余元用于科技进步的项目,实现了高炉喷吹煤粉,连铸,连轧,热电联产等工艺技术并已取得了显著的经济效益,经济技术指标水平明显提高,有力地促进了企业的发展,提高了市场竞争的能力,保证了经济效益的提高,为“九五”的进一步发展奠定了基础。  相似文献   

3.
大型顶吹平炉投产以来,由于降碳速度快,因而造渣困难,脱硫能力差,长期不能冶炼硅钢。针对上述问题,对造渣工艺进行改革,获得成功,不仅降低了消耗,提高了质量,缩短了熔炼时间,而且也满足了用户对硅钢的要求,同时,取得了较大的经济效益。  相似文献   

4.
热电厂煤气加压站经过系统优化改造后,设备运行可靠,操作方便,满足了生产工艺要求,实现了变频调速,消除了煤气的泄漏现象,达到了节电,节油,节约维修费用的目的,经济效益可观。  相似文献   

5.
本文介绍10t“0”型龙门吊通过静定车架结构代替传统的超静定结构的改进,其造型美观,受力合理,降低了精度要求,节省了大量的材料,降低了成本,使制造工艺更加方便,大大降低了金属结构的自重,改善了起重机的运行状态,延长了驱动车轮的寿命,故障率低,维修费用少。  相似文献   

6.
本文叙述了国内先进的煤气净化工艺和氨、硫回收装置,净化了焦炉煤气,减少了环境污染,改善了硫铵质量,增加了硫磺新产品,提高了生产管理水平,确保了安全生产。  相似文献   

7.
铝-钪(2%)合金的制备   总被引:4,自引:0,他引:4  
传统的生产铝钪合金的方法,成本高,条件复杂,不利于工业生产,我们对金属热还原制取A1—Sc合金进行了研究,简化了生产条件,降低了对原料的要求,缩短了工艺流程,降低了生产铝钪合金的成本,开拓了铝钪合金的应用市场。  相似文献   

8.
这次会议,传达了全国高教管理体制改革工作座谈会精神,听取了徐部长的重要讲话,交流了冶金高校近几年来管理体制改革的情况和体会,研究了改革过程中存在的有关困难和问题,讨论了进一步推动冶金高教管理体制改革的相应措施。这是一次很重要的会议,通过会议,大家进行了热烈地讨论,进一步提高了认识,明确了方向,这对进一步推进冶金高教管理体制深化改革必将起到重要作用。下面,我就有关问题讲几点意见。  相似文献   

9.
湖北丹江哆嗦业公司三期技改工程供电整流系统采用了较多的新技术,新设备,新工艺,在该前提下,对运行参数进行详细研究,达到合理利用电能的目的,同时采用全面质量管理工作的方法,成功地改善了电流的稳定性,减少了设备停运率,为安全生产提供了有力的保障,达到了节能降耗的目的,取得了一定的经济效益。  相似文献   

10.
基于问题原型的采矿方法选择专家系统的研究   总被引:1,自引:1,他引:0  
杨洪军  黄士芳 《黄金》1997,18(10):19-22
本文针对矿山的实际需要,以矿山工作人员应用对象,在充分分析矿块回采问题的基础上,提出了三种问题原型,建立了领域问题的知识库,编制了推理机,用户接口,解释,知识库管理等程序模块,形成了采矿专家系统的框架,为进一步开发奠定了基础。  相似文献   

11.
Within-child associations between family income and child externalizing and internalizing problems were examined using longitudinal data from the NICHD Study of Early Child Care and Youth Development (2004a, 2004b; N = 1,132). Variations in income effects were estimated as a function of whether families were poor, whether mothers were partnered, and the number of hours mothers and their partners were employed. On average, children had fewer externalizing problems during times when their families' incomes were relatively high than during times when their families' incomes were relatively low; the estimated benefits of increased income were greatest for children who were chronically poor. For both externalizing and internalizing problems, income was most strongly associated with problems when chronically poor children's mothers were partnered and employed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

12.
15-5PH steel is one of the martensitic precipitation-hardened stainless steels, which is extensively applied in the aero shafts, and electron beam welding is a significant procedure to manufacture the parts. To verify the dimension accuracies and properties, EBW with oscillation was employed on the cylinders of 15-5PH steel. The welding distortions were measured, and the microstructures and tensile properties of the joints were investigated. The weld appearances of the cylinders were smooth, and the morphology was parallel. After EBW, the shrinkages of the cylinders were above ?0.22?mm, and the welding distortions were ?0.66 to ?1.1‰, and the straightnesses were less than 1‰ due to the distortions. The martensites and a few austenites were in the welds of the cylinders after heat treatment, and the microhardnesses in the welds were 445 HV0.2, which were bigger and more homogeneous than those of the as-welded. The tensile strength and yield strength of the joints were respectively 1300 and 1150?MPa, which were higher than those of the as-welded joints, and the elongation rate of the joints was 10%. The microstructures and properties of the cylinders conformed to the aero shafts, which was attributed to the microstructure transformation with oscillation EBW and heat treatment.  相似文献   

13.
系统汇集了20世纪70年代以来我国使用X射线荧光光谱(XRF)分析技术进行铁矿石分析的文献共计101篇,其中熔融制样法文献78篇,粉末压片法文献11篇,能量色散仪器分析及野外现场应用文献12篇。首先介绍了铁矿石分析的基础条件:包括专著、标准物质、标准方法和综合性评述论文;然后采用表格方式对文献要点进行了介绍, 按熔融法、粉末压片法、能量色散多元素分析方法进行了重点评介;最后讨论了铁矿石分析中常遇到的粒度、矿物效应,制样方法选择和内标的应用等实际问题。对XRF在铁矿石分析中的某些重要问题进行了探讨,并对XRF分析铁矿石的应用前景作了展望。文献表明:XRF技术已经成为铁矿石主、次量元素分析最重要的分析方法之一。全篇引文151篇。  相似文献   

14.
A geotextile-reinforced embankment was built over soft ground. Staged construction and vertical prefabricated drains were used to obtain strength gain via consolidation of the foundation material. Settlement and pore pressure were measured as a part of construction control. Settlement, differential settlement, and rate of consolidation were predicted by simple models. Uncertainties in the predictions were evaluated to assess the reliability of the predictions. The estimated errors were compared with the measured values, and major contributors to prediction errors were identified.  相似文献   

15.
通过2种途径将熔体快淬法制得的FeCuNbSiB非晶薄带制成环状粘结磁体。一是将非晶薄带进行晶化处理,再将晶化后的薄带粉碎成不同粒度的粉末,然后与粘结剂相混合制成粘结磁体。二是将非晶薄带直接粉碎成不同粒度的粉末,再将此粉末进行晶化处理,将晶化后的磁粉与粘结剂相混合制成粘结磁体。分析了磁粉粒度和模压压力对粘结磁体性能的影响。并对两种粘结磁体的性能进行比较。结果表明,第一种方法制备的粘结磁体的性能优于第二种。  相似文献   

16.
系统汇集了20世纪70年代以来我国使用X射线荧光光谱(XRF)分析技术进行铁矿石分析的文献共计101篇,其中熔融制样法文献78篇,粉末压片法文献11篇,能量色散仪器分析及野外现场应用文献12篇。首先介绍了铁矿石分析的基础条件:包括专著、标准物质、标准方法和综合性评述论文;然后采用表格方式对文献要点进行了介绍, 按熔融法、粉末压片法、能量色散多元素分析方法进行了重点评介;最后讨论了铁矿石分析中常遇到的粒度、矿物效应,制样方法选择和内标的应用等实际问题。对XRF在铁矿石分析中的某些重要问题进行了探讨,并对XRF分析铁矿石的应用前景作了展望。文献表明:XRF技术已经成为铁矿石主、次量元素分析最重要的分析方法之一。全篇引文151篇。  相似文献   

17.
In this paper, efficiency and effectiveness of carbon fiber-reinforced polymers (CFRP) in upgrading the shear strength and ductility of seismically deficient beam-column joints have been studied. For this purpose, four reinforced concrete interior beam-column sub-assemblages were constructed with nonoptimal design parameters (inadequate joint shear strength with no transverse reinforcement) representing preseismic code design construction practice of joints and encompassing the vast majority of existing beam-column connections. Out of these four, two specimens were used as baseline specimens (control specimens) and the other two were strengthened with CFRP sheets under two different schemes (strengthened specimens). In the first scheme, CFRP sheets were epoxy bonded to the joint, beams, and part of the column regions. In the second scheme, however, sheets were epoxy bonded to the joint region only but they were effectively prevented against any possible debonding through mechanical anchorages. All four subassemblages were subjected to cyclic lateral load histories so as to provide the equivalent of severe earthquake damage. Further, the damaged control specimens were repaired after filling the cracks through epoxy and wrapping them with CFRP sheets under the same two above-mentioned schemes. These repaired specimens were subjected to the similar cyclic lateral load history and their response histories were obtained. Hence, a total of six specimens were tested: two control; two strengthened; and two repaired. Response histories of control, repaired, and strengthened specimens were then compared. The results were compared through hysteretic loops, load-displacement envelopes, column profiles (maximum horizontal displacements of column along its height), joint shear distortion, ductility, and stiffness degradation. The comparison shows that CFRP sheets improve the shear resistance of the joint and increase its ductility. Results of two chosen schemes of strengthening were also compared and the importance of beam upgrading was highlighted.  相似文献   

18.
 On the basis of the uniform design method, six kinds of martensitic hot work die steels were designed. The phase transformation temperatures including Ac1, Ac3, and Ms were measured by DIL805A quenching dilatometer. The influences of the main elements on phase transformation temperatures were analyzed by quadratic stepwise regression analysis, and three corresponding equations were obtained. These equations, in which the interactions of the elements were considered, showed more effectiveness than the traditional ones. In addition, the thermal expansion coefficients of these steels in annealed state and quenched state were also obtained during the tests. The influences of chemical composition and temperature on the thermal expansion coefficient were analyzed; the equations obtained were verified by using several kinds of steels. The predicted values were in accordance with the results of the experiments.  相似文献   

19.
全层TiAl基合金室温断裂机制的研究   总被引:1,自引:1,他引:1  
通过拉伸、压缩、弯曲实验分析研究了全层(FL)组织TiAl基合金的断裂机制。研究发现:拉伸和压缩时材料抵抗裂纹的扩展能力不同,抗压强度远高于抗拉强度,这是由于两者的变形及断裂机制不同。TiAl基合金拉伸断裂机制为脆性解理断裂,压缩变形断裂是剪应力和正应力共同作用下的断裂,是准解理断裂。TiAl基合金的缺口弯曲断裂方式也为解理断裂,其断裂过程是先在缺口处产生微裂纹,一旦裂纹在缺口根部产生,由于材料已积累足够的能量使得材料快速失稳解理断裂。  相似文献   

20.
采用氢氧化钾碱熔法处理样品,以铑校正铍、铯、铊、铪、铀、钍,以铼校正镓、铌、钽、锆,建立了电感耦合等离子体质谱法测定铍、铯、镓、铊、铌、钽、锆、铪、铀、钍10种元素的方法。分别选用银坩埚、镍坩埚、刚玉坩埚熔融空白样品进行试验,结果表明,采用银坩埚时各元素的空白响应信号值与镍坩埚和刚玉坩埚相比均较低。对熔融条件进行了优化,确定熔融温度为600℃、熔融时间为8min。分别采用去离子水、2%(体积分数)硝酸上机测量,并记录各元素的响应信号值,与测定地质实际样品中各元素的响应信号值进行对比,结果表明,其对测定结果的影响可以忽略不计。在优化的实验条件下,各元素校准曲线线性相关系数均在0.9990以上,方法的检出限为0.023~0.049μg/g,测定下限为0.078~0.16μg/g。采用实验方法对岩石成分分析标准物质中铍、铯、镓、铊、铌、钽、锆、铪、铀、钍10种元素进行测定,测定结果与认定值基本一致,相对误差(RE)在-8.3%~9.6%之间,相对标准偏差(RSD,n=11)均不大于4.2%。采用实验方法对2个从野外采回的地质实际样品进行测定,并加入岩石成分分析标准物质进行加标回收试验,上述10种元素的回收率在96%~102%之间。  相似文献   

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