镝铁阴极电蚀对稀土电解槽的电解特性影响分析

随着稀土熔盐电解槽电解过程的进行,阴极形状会随着时间的推移发生电腐蚀,电解槽底部阴极锥角α不断增大,对电解效率与热场产生了一定影响.以越南镝铁阴极稀土电解槽为研究对象,利用COMSOL多物理场耦合软件,计算了稀土电解槽中阴极不同电解阶段不同阴极形状的电解特性参数,得到了电解槽中不同阴极锥角α值与最大电流密度关系曲线图,并分析了电解槽内阴极电蚀对整个电解反应过程的影响,为电解槽的后期维护提供了参考依据.      

镝铁阴极电蚀对稀土电解槽电解特性的影响

随着稀土熔盐电解槽电解过程的进行,阴极形状会随着时间的推移发生电腐蚀,电解槽底部阴极锥角α不断增大,对电解效率与热场产生了一定影响.以越南镝铁阴极稀土电解槽为研究对象,利用COMSOL多物理场耦合软件,计算了稀土电解槽中阴极不同电解阶段不同阴极形状的电解特性参数,得到了电解槽中不同阴极锥角α值与最大电流密度关系曲线图,并分析了电解槽内阴极电蚀对整个电解反应过程的影响,为电解槽的后期维护提供了参考依据.     

石墨化阴极炭块在400kA节能型电解槽上的应用

石墨化阴极具有良好导热性、高电导率、低电阻率、低钠膨胀率等特点,采用石墨化阴极炭块及其配套技术可以提高电解槽的磁流体稳定性,降低电解槽的阴极压降,延长电解槽寿命,为电解槽在低电压下稳定运行创造条件。本文详细阐述了铝电解槽阴极炭块的选择标准、石墨化阴极的特点和石墨化阴极炭块的工程应用实例。     

168kA新型阴极高效节能铝电解槽磁流体运动的数值模拟

建立了168 kA新型阴极铝电解槽磁流体运动的数学模型,对电解质与铝液交界面的流场、电解质的流场以及阴极铝液的流场进行了模拟,并对新型阴极电解槽阳极导杆等距电压降进行了测量。研究结果表明：新型阴极铝电解槽可隔断槽内铝液流动,降低槽内阴极铝液的流速。新型阴极铝电解槽铝液与电解质交界面的速度矢量和较普通阴极铝电解槽铝液与电解质交界面的速度矢量和低2～3倍,且极值分布更为均匀。新型阴极电解槽内铝液与电解质界面处的磁流体速度最大,然后以界面为中心线逐渐减小。     

60kA铝电解槽寿命初探

根据 6 0kA铝电解槽炉膛变化情况、大修槽阴极方钢和阴极炭块破损情况分析 ,初步探讨了6 0kA铝电解槽寿命同电解槽炉膛、阴极方钢质量、阴极炭块质量之间的关系     

铝电解高效节能技术应用与研究现状

近年来,新型阴极结构铝电解技术在国内众多铝厂得到推广与应用.本文介绍了新型阴极结构电解槽的结构特点.结合数家铝厂的新型阴极结构电解槽实际运行情况,分析与探讨了新型阴极结构电解槽内衬结构、热平衡、电流效率、铝液面稳定性、槽内磁场特点,以及阴极凸起的磨蚀与消耗问题,以及新型阴极结构电解槽在操作与管理上的若干问题.     

大型预焙铝电解槽阴极隆起的应对策略与生产实践

针对铝电解槽阴极炉底隆起,本文研究了铝电解槽阴极上隆的原因,分析了阴极隆起的危害,结合生产实践进行了控制阴极隆起的探索,找到了消除阴极隆起的工艺控制方法。     

中铝贵州工服电解阴极钢棒热熔焊接试验成功

中铝贵州工服公司采用热熔焊接铝电解槽阴极钢棒的试验获得成功,标志铝电解槽阴极钢棒焊接工艺引入了全新的技术。热熔焊接铝电解槽阴极钢棒,是将铝热反应药剂放入位于两段阴极钢棒间并进行加热熔化焊接。     

铝电解槽阴极软带维修工艺改进

通过对电解槽阴极软带维修工艺的研究,针对目前维修工艺所存在的问题,提出了电解槽阴极软带维修施工操作要点及质量改进措施,提高了电解槽阴极软带维修质量。     

500kA铝电解槽阴极破损分析及对策

某电解铝厂500 kA铝电解槽由于电磁场、热平衡设计不合理，工艺运行参数不匹配，电解槽早期破损严重，给电解槽长寿命、高效率运行带来巨大的风险。本文通过对电解槽进行解剖，深入分析电解槽阴极炭块破损机理，可知电解槽早期破损主要分为槽壳变形、阴极炭块破损、侧部破损等几大类。为了解决阴极破损问题，在不改变阴极母线结构的前提下对电解槽内衬、工艺技术参数等方面进行深度优化，最终有效解决了电解槽早期破损的问题，实现了延长电解槽寿命的目的。     

Inhibin A is a sensitive and specific marker for testicular sex cord-stromal tumors

We compared the expression of inhibin A, chromogranin, synaptophysin, S-100 protein, cytokeratins AE1/AE3, 7, and 20, and estrogen and progesterone receptors in testicular sex cord-stromal tumors: 11 Sertoli cell tumors, 3 Sertoli cell adenomas (nodules), 26 benign Leydig cell tumors, 7 malignant Leydig cell tumors (defined clinically by metastatic behavior), and a variety of germ cell tumors. Inhibin was the most sensitive marker, expressed in 91% of the Sertoli cell tumors and 100% of the Sertoli cell adenomas and Leydig cell tumors. The non-neoplastic Sertoli and Leydig cells invariably stained for inhibin. Conversely, no germ cell tumors were immunoreactive. One testicular tumor of the adrenogenital syndrome was immunoreactive. Neuroendocrine marker immunoreactivity was variable. Chromogranin was expressed in the non-neoplastic Sertoli and Leydig cells, 82% of the Sertoli cell tumors, 92% of the benign Leydig cell tumors, and 43% of the malignant Leydig cell tumors. Synaptophysin was expressed in the non-neoplastic Sertoli and Leydig cells, 45% of the Sertoll cell tumors, and 70% of the Leydig cell tumors, in approximately similar proportions between the benign and malignant Leydig cell tumors. S-100 protein was expressed in 64% of the Sertoli cell tumors, 8% of the benign Leydig cell tumors, and none of the malignant Leydig cell tumors. Cytokeratins AE1/AE3 were expressed in 64% of the Sertoli cell tumors and 42% of the Leydig cell tumors, with similar proportions in the benign and malignant cases. Estrogen and progesterone receptor expression were identified in 24 and 39% of benign and malignant Leydig cell tumors, respectively. We conclude that inhibin is a characteristic marker for Sertoli and Leydig cells and that it serves to differentiate testicular sex cord-stromal tumors from germ cell tumors.     

Action potential conduction between a ventricular cell model and an isolated ventricular cell

We used the Luo and Rudy (LR) mathematical model of the guinea pig ventricular cell coupled to experimentally recorded guinea pig ventricular cells to investigate the effects of geometrical asymmetry on action potential propagation. The overall correspondence of the LR cell model with the recorded real cell action potentials was quite good, and the strength-duration curves for the real cells and for the LR model cell were in general correspondence. The experimental protocol allowed us to modify the effective size of either the simulation model or the real cell. 1) When we normalized real cell size to LR model cell size, required conductance for propagation between model cell and real cell was greater than that found for conduction between two LR model cells (5.4 nS), with a greater disparity when we stimulated the LR model cell (8.3 +/- 0.6 nS) than when we stimulated the real cell (7.0 +/- 0.2 nS). 2) Electrical loading of the action potential waveform was greater for real cell than for LR model cell even when real cell size was normalized to be equal to that of LR model cell. 3) When the size of the follower cell was doubled, required conductance for propagation was dramatically increased; but this increase was greatest for conduction from real cell to LR model cell, less for conduction from LR model cell to real cell, and least for conduction from LR model cell to LR model cell. The introduction of this "model clamp" technique allows testing of proposed membrane models of cardiac cells in terms of their source-sink behavior under conditions of extreme coupling by examining the symmetry of conduction of a cell pair composed of a model cell and a real cardiac cell. We have focused our experimental work with this technique on situations of extreme uncoupling that can lead to conduction block. In addition, the analysis of the geometrical factors that determine success or failure of conduction is important in the understanding of the process of discontinuous conduction, which occurs in myocardial infarction.     

Rapid isolation of cell-type-specific protein tyrosine kinases by degenerate polymerase chain reaction combined with differential hybridization technique

To identify protein tyrosine kinase (PTK) genes preferentially expressed in renal cell carcinoma cell line, we screened a PTK-cDNA-enriched library constructed from RNA of an renal cell carcinoma cell line with a PTK probe, each produced from renal cell carcinoma, gastric cancer or esophageal cancer cell lines by degenerate polymerase chain reaction. Two cDNA fragments of PTK genes, FRK and FLT-3, were isolated from the PTK-cDNA-enriched library of the renal cell carcinoma cell line by differential hybridization technique. The FRK cDNA clone represented 15.8% of the PTK-cDNA-enriched library from the renal cell carcinoma cell line, while the FLT-3 cDNA clone was 2.8% of the same library. Both of the two PTK genes were expressed preferentially in renal cell carcinoma cell lines. This method, described here, is useful for the rapid isolation of PTK cDNA fragments, including a low abundant cDNA, preferentially expressed in a specific cell line.     

NK/T细胞淋巴瘤细胞凋亡和细胞增殖特征及意义

Objective:The aim was to study the features and clinical significance of cell apoptosis and proliferation of NK/T cell lymphoma. Methods:TdT-mediated dUTP nick end labeling and immunohistochemical Streptavidin-peroxidase method were used to study cell apoptosis and the expression of proliferation cell nuclear antigen in 25 NK/T cell lymphoma and 10reactive lymphoid tissues. Results:Apoptotic index (AI) and proliferative index (PI) averaged (1.92% ± 0.86%) and (41.48%± 5.10%) respectively in the 25 NK/T cell lymphomas and (6.70% ± 1.89%) and (20.10% ± 2.77%) in the 10 reactive lymphoid tissues. Compared with reactive lymphoid tissues, AI was significantly reduced in NK/T cell lymphoma (t = 10.80, P < 0.01)while PI significantly increased (t = 12.39, P < 0.01). In addition, in NK/T cell lymphoma, AI and PI were positively related (r = 0.69, P < 0.01). Conclusion:In NK/T cell lymphoma, cell apoptosis is reduced while cell proliferation increased. The imbalance between cell apoptosis and cell proliferation is closely related to the development and progression of NK/T cell lymphoma.     

From bioenergetics to philosophy of science: a brief report of an exciting cultural journey

Continuous human leukemia-lymphoma cell lines have become indispensable tools in hematological research since the establishment of the first human lymphoma cell line Raji in 1963. We summarize here historical landmarks in the establishment of unique leukemia-lymphoma-derived cell lines from the various cell lineages; their special importance in hematopoietic research is emphasized. The first cell lines were derived from African Burkitt lymphomas and were found to integrate the Epstein-Barr virus in their genome leading to the discovery and isolation of this virus. However, it was later recognized that not every cell line derived from a patient with leukemia-lymphoma represents a malignant cell line as residual normal B-lymphocytes can also be immortalized by EBV infection. During the following 20-30 years many other types of hematopoietic cell lines, commonly derived from hematopoietic neoplasms, were established. These panels of cell lines now span almost the whole spectrum of hematopoietic cell lineages (except for dendritric cells) and the various distinct stages of differentiation along the respective cell axes. From early on, cell lines became important tools for basic and clinical hematological research, initially mainly in the field of immunology, but later expanding to other areas also. It became apparent that leukemia-lymphoma cell lines are of monoclonal origin, are arrested at a discrete maturational stage during differentiation in each lineage, and show sustained and growth factor-independent or -dependent unlimited proliferation. Categorization of cell lines might best be based on the physiological stages of hematopoietic differentiation in the various cell lineages. For an adequate classification, detailed characterizations of both the cell lines and the primary cells from which the cell lines originated are absolutely mandatory. In summary, the availability of large numbers of continuous leukemia-lymphoma cell lines has greatly facilitated clinical and immunobiological studies of normal and malignant hematopoiesis. Human leukemia-lymphoma cell lines will continue to provide exquisite model systems for many biomedical disciplines.     

Quantitative analysis of biological marker synthesis in tumor cell cycle

A quantitative relationship between tumor cell number and biologic marker concentration has been investigated and characterized by the previously developed discrete-time kinetic model for the study of cell kinetics. Here, this model is further expanded to cope with both cell cycle kinetics and biologic marker synthesis. A synchronized tumor-cell population is examined to determine the time course of the synthesis of markers in relation to cell cycle. The DNA content distributions, measured by flow microfluorometry, are analyzed by use of the model, and the cell age distribution is extracted. The average marker content per cell in cell cycle is measured for each time sequence in synchronized cell populations. The model, incorporating the cell age distribution and the average marker content per cell in cell cycle, enables one to generate the marker content distribution, from which the cell number is estimated from the marker concentration. The model performance is further evaluated with Chinese hamster ovary cells, and their polyamine content and the total polyamine concentration during synchronization is calculated and related to the total cell number.     

无内衬电解槽在有色金属湿法冶金中的发展及应用

介绍了有色金属湿法冶金精炼工艺中应用的耐腐蚀整体玻璃钢电解槽、玻璃钢筋树脂砼电解槽、抗裂耐酸砼电解槽的特点以及无内衬电解槽在有色行业的应用情况,分析了电解槽的发展方向等。     

无内衬电解槽在有色金属湿法冶金中的发展及应用

介绍了有色金属湿法冶金精炼工艺中应用的耐腐蚀整体玻璃钢电解槽、玻璃钢筋树脂砼电解槽、抗裂耐酸砼电解槽的特点以及无内衬电解槽在有色行业的应用情况,分析了电解槽的发展方向等。     

大型预焙铝电解槽的安全管理

近年来,我国电解铝生产槽逐步向大电流大容量发展,以解决能耗高、技经指标低的问题,但大型槽一旦发生漏槽,处理不及时后果不堪设想。本文就大型铝电解槽防止漏槽,在安全管理方面进行探讨,以减少或避免大型预焙铝电解槽漏槽引发安全事故,从而提高电解铝生产经营效益。     

Characterization of ethanol-sensitive and insensitive fibroblast cell lines expressing human L1

Ethanol inhibits L1-mediated cell-cell adhesion in fibroblast cell lines stably transfected with human L1. Here we show that this action of ethanol is present in only a subset of transfected NIH/3T3 and L cell clonal cell lines. All L1-expressing cell lines had higher levels of cell adhesion than cell lines transfected with empty vector. In all ethanol-sensitive cell lines, L1-mediated adhesion was inhibited by ethanol (IC50 5-10 mM), 2 mM butanol, but not 5 mM pentanol. In contrast, ethanol-insensitive cell lines were not inhibited by up to 200 mM ethanol, 2 mM butanol, or 5 mM pentanol. Ethanol sensitivity or insensitivity was a stable property of each cell line and was not associated with differences in electrophoretic mobility, abundance, or cell surface localization of L1. Fab fragments prepared from anti-L1 polyclonal antisera inhibited cell adhesion only in the ethanol-sensitive cell lines. These data suggest that L1 may exist in an alcohol-sensitive or an alcohol-insensitive state that may be governed by host cell factors.