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1.
针对3KA电解槽温度实际分布研究的不足,通过设计实验装置实际测量了Nd2O3-NdF3-LiF熔盐电解槽内温度分布,并对其外部影响因素进行了分析.研究结果表明:电解槽内温度纵向分布是从上到下先升高再下降,横向分布是从阴极到阳极先下降再升高,电解过程中电化学反应主要集中在电解槽的中部,热量是影响温度变化的主要因素.  相似文献   

2.
A data acquisition system based on LabVlEW is designed and implemented, and electrodischarge(ED) fine truing of metal-bonded fine-grain diamond wheel based on real-time monitoring is researched. Real-time monitoring not only makes efficient impulse specification of ED truing easily obtained, but also is good for timely identifying no-load, avoiding short circuit and arc discharge phenomena and then for obtaining normal machining state. ED fine truing of the fine-grain wheel includes two steps: rough truing for high efficiency and fine truing for high precision. Final ED truing precision and efficiency not only depend on electric process specification, but also is concerned with electrode shape, insulated performance of operating fluid and vertical feed quantity value and frequency. Experiments indicate that ED fine truing based on real-time monitoring can improve the truing precision and efficiency. Average machining efficiency of W10 wheel is about 0.95μm/min; the final run-out by ED truing is less than 2μm.  相似文献   

3.
特殊工件精密磨削是一个复杂的多变量影响过程,本文开展了精密磨削加工技术的优化研究。在利用已知加工外表面母线方程的基础上,采用了精密数控曲线磨削砂轮法向跟踪的方法,通过保证曲线轮廓上磨削点处的法线经过砂轮的回转平面,实现了砂轮与工件之间的恒定点接触,在分析砂轮与工件运动几何关系的基础上,建立了砂轮法向跟踪的数学模型,从而提高了加工精度,实现了对任意复杂曲线轮廓的磨削加工。  相似文献   

4.
采用价廉的涤纶滤膜作为电解体系隔膜,利用阴、阳极同时作用降解含酚工业废水,在反应时间80min,曝气量1.2L/min,电流密度30mA/cm2的最佳条件下,含酚废水COD去除率可达到80%,阴极室COD去除率高于阳极室。  相似文献   

5.
A unity transformation model (UTM) was presented for flexible NC machining of spiral bevel gears and hypoid gears. The model can support various machining methods for Gleason spiral bevel gears and hypoid gears, including generation machining and formation machining for wheel or pinion on a universal five-axis machining center, and then directly produce NC codes for the selected machining method. Wheel machining and pinion machining under UTM were simulated in Vericut 6.0 and tested on a five-axis machining...  相似文献   

6.
服装外轮廓原意是影像、剪影、侧影、轮廓,在服装设计上引申为外形、外廓线、大形、廓型等意思。服装外轮廓是一种单一的色彩形态,人眼在没有看清款式细节以前首先感觉到服装的外轮廓。服装廓型是服装整体外形。形状广泛,种类丰富。不同的服装廓型。预示着服装的流行趋势。在掌握其廓型设计元素的同时,对不同的廓型进行合理搭配组合,可提高服装的品质和竞争力。  相似文献   

7.
Li  Kai  Fan  Qun  Chuai  Hongyuan  Liu  Hai  Zhang  Sheng  Ma  Xinbin 《天津大学学报(英文版)》2021,27(3):202-216

As an energy-intensive industry, the chlor-alkali process has caused numerous environmental issues due to heavy electricity consumption and pollution. Chlor-alkali industry has been upgraded from mercury, diaphragm electrolytic cell, to ion exchange membrane (IEM) electrolytic cells. However, several challenges, such as the selectivity of the anodic reaction, sluggish kinetics of alkaline hydrogen evolution, degradation of membranes, the reasonable design of electrolytic cell structure, remain to be addressed. For these reasons, this paper mainly reviews the research progress of the chlor-alkali industry from materials to devices, including hydrogen evolution anode, chlorine evolution cathode, IEM, and electrolytic cell system. Finally, the research directions and prospects in the chlor-alkali industry are proposed for its further improvement.

  相似文献   

8.
质子交换膜燃料电池的水管理是影响其性能的重要因素之一。电池水管理的目的就是要实现尽可能高的膜的水合程度,降低膜的阻抗。为了更好实现以上目标,文中建立了电池水传输模型,基于模型利用工程逼近分析方法,分析了阴阳极湿度、反应气体流量对膜的水含量和阴阳极水分压的影响。仿真结果通过与其他模型相比较,取得了一致的结果,因此也证明了该模型的有效和实用性。基于以上的分析结果为建立简化的膜水含量控制模型和实现水管理的控制目标奠定基础。  相似文献   

9.
固定阴极电化学射孔的成型规律研究   总被引:1,自引:0,他引:1  
根据电场理论,提出了一种研究固定阴极电化学射孔成型规律的更为严密的处理方法, 且基于这种思路分析了该加工方式下阴极表面电荷密度及加工区电场强度、电流密度、加工速度等在加工过程中的变化规律,建立了加工中间隙变化的数学模型,并给出了相关的实验结果,为这种简易加工方式的合理应用提供了理论依据.,A kind of new idea based on electromagnetic theory is presented, and it is used in research of the shaping law of electrochemical perforation with fixed cathode. The changing laws of the electric field vectors at certain point on the surface of the anode workpiece with machining time, such as the electric field intensity E, the current density j and so on, are introduced. The mathematical model of the perforating velocity is presented, moreover, the experimental result to verify it is given at the end of the paper.  相似文献   

10.
A unity transformation model (UTM) was presented for flexible NC machining of spiral bevel gears and hypoid gears. The model can support various machining methods for Gleason spiral bevel gears and hypoid gears, including generation machining and formation machining for wheel or pinion on a universal five-axis machining center, and then directly produce NC codes for the selected machining method. Wheel machining and pinion machining under UTM were simulated in Vericut 6.0 and tested on a five-axis machining center TDNC-W2000 with NC unit TDNC-H8. The results from simulation and real-cut verify the feasibility of gear machining under UTM as well as the correctness of NC codes.  相似文献   

11.
利用电化学技术,以试样为阳极,白金为阴极,进行电解,根据试样同参比电极之间的电位差随时间变化的曲线得出溶解反应的终点,从而求出铬、氧化铬溶解所需的电量,根据法拉第定律计算出镀层的重量;根据电解法的校准系数K得到镀铬板的氧化铬。通过实际生产试样进行电解法与化学法的比对,检测精度满足生产要求。  相似文献   

12.
从对小说《心是孤独的猎手》的文本分析入手,通过对人物之间轮辐结构和上帝形象的分析,试图找出这种结构本身的虚空与人物的信仰危机之间的联系。讨论得出位于中轴位置的辛格,实际代表了沉默的上帝,并认为20世纪宗教信仰根基的动摇,轮辐最终只是虚空,不能带动人类历史车轮的转动,走向生活的和谐与安详。最后回归到作品题目所表达的追逐的徒劳。  相似文献   

13.
This research investigated students' understanding of electrochemistry following a 7–9-week course of instruction. A list of conceptual and propositional knowledge statements was formulated, and this provided the framework for semistructured interviews that were conducted with 32 students in their final year of high school chemistry, following instruction in electrochemistry. Three misconceptions identified in this study and five which have been reported earlier are incorporated into an alternative framework about electric current. The framework is grounded on the notion that a current always involves drifting electrons, even in solution. Another area where students' misconceptions were prevalent was in relation to the sign of the anode and cathode. Students who thought the anode was negatively charged believed cations would move toward it, and those who thought it was positively charged were unable to explain why electrons move away from it. Electrolytic cells also proved troublesome for students. Many students did not associate the positions of the anode and cathode with the polarity of the applied electromotive force (e.m.f.). Other students attempted to reverse features of electrochemical cells and apply the reversals to electrolytic cells. The implications of the research relate to students' interpretation of the language that is used to describe scientific phenomena and the tendency for students to overgeneralize, due to comments made by teachers or statements in textbooks.  相似文献   

14.
基于工作过程的课程开发是现代职业教育改革与发展的趋势;结合数控加工技术类课程项目的改革,本文在非圆曲线轮廓的回转体类零件加工中,以典型椭圆轮廓零件为案例,编制宏程序应用在数控车床中,这对职业院校课程改革和企业实际工作相结合具有一定的借鉴作用。  相似文献   

15.
反转法建立解析式求出凸轮理论廓线方程,再根据包络原理求出实际廓线方程和铣刀加工中心轨迹方程。同时计算出凸轮压力角及其曲率半径验证凸轮设计的合理性和可行性。通过编程运算可对复杂凸轮轮廓曲线精确求解而获得数控加工过程中走刀路线上各点的坐标。  相似文献   

16.
针对线切割加工的特点,讨论了微小齿轮的设计和主要参数的确定,舍弃了普通齿轮设计方法中对参数的一些限制条件,使微小齿轮的设计更加灵活.基于齿轮啮合理论,研究了渐开线微小齿轮轮廓的生成算法.分析了齿轮啮合中的齿廓干涉现象,设计了齿轮啮合过程仿真算法.基于ACIS几何平台,开发了面向线切割的微小齿轮设计和啮合仿真软件,实现了微小齿轮的造型,并可进行啮合过程仿真和干涉检验.最后通过一对微小齿轮的设计制造实验,验证了该方法的可行性.  相似文献   

17.
在陶瓷材料的磨削加工过程中 ,金刚石砂轮特性和磨削用量直接影响磨削表现质量。文章把明确表征金刚石砂轮特性的主要指标参数进行综合 ,在一定假设条件下建立了砂轮特性参数和磨削用量间的函数关系 ,进一步利用MAT LAB分析软件 ,对这些参数和磨削用量之间的相互关系和相互影响进行了可视化研究 ,从某些方面解决了磨削加工过程中砂轮特性参数和磨削用量的选择问题。特别是在选定某一磨削用量数值后 ,如何确定其余磨削用量的选择范围问题。  相似文献   

18.
In this paper, a 60 kW proton exchange membrane fuel cell (PEMFC) generation system is modeled in order to design the system parameters and investigate the static and dynamic characteristics for control purposes. To achieve an overall system model, the system is divided into five modules: the PEMFC stack (anode and cathode flows, membrane hydration, and stack voltage and power), cathode air supply (air compressor, supply manifold, cooler, and humidifier), anode fuel supply (hydrogen valve and humidifier), cathode exhaust exit (exit manifold and water return), and power conditioning (DC/DC and DC/AC) modules. Using a combination of empirical and physical modeling techniques, the model is developed to set the operation conditions of current, temperature, and cathode and anode gas flows and pressures, which have major impacts on system performance. The current model is based on a 60 kW PEMFC power plant designed for residential applications and takes account of the electrochemical and thermal aspects of chemical reactions within the stack as well as flows of reactants across the system. The simulation tests show that the system model can represent the static and dynamic characteristics of a 60 kW PEMFC generation system, which is mathematically simple for system parameters and control designs.  相似文献   

19.
针对圆弧金刚石砂轮磨损检测及砂轮修形的实际需要,通过研究圆弧金刚石砂轮的在位测量原理,设计相应的软硬件控制方案.利用KEYENCE公司LK-G1O高精度激光位移传感器,设计圆弧金刚石砂轮的精密在位检测系统,实现圆弧金刚石砂轮表面轮廓的精密检测.实验结果表明:该检测系统适用于圆弧金刚石砂轮精密测量和评价,为光学非球面磨削加工提供参数依据.  相似文献   

20.
通过测量和分析高频感应钎焊金刚石砂轮磨削大理石过程中的磨削力,对砂轮所受的法向力和切向力进行了研究。从单颗金刚石最大切削厚度的角度。分析了磨削深度、进给速度和砂轮线速度时磨削力的影响。  相似文献   

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