超大截面长距离电缆敷设专用工具的研制与应用

本工具的研制主要基于阳江核电一期百万千瓦机组BOP及常规岛建安工程,贯穿厂区的电缆主要在GB电气技术廊道内,电气廊道内空间狭小。进行电缆截面500mm2大截面长距离电缆敷设,如采用原由纯人工敷设方法,难以保证工期。为此,通过现状分析与调研,提出多套方案进行试验论证,成功研制出超大截面长距离电缆敷设专用工具,并该工程中应用。采用该工具敷设的电缆排列整齐,电缆无应力,外观无明显划伤,电缆耐压等试验数值均符合国标要求,敷设工艺得到了中广核工程公司高度认可。     

大学英语教学中中国文化地位的建立

大学英语教学中的文化传播主要以西方文化的单向输入为主,中国文化基本处于失语状态。要改变这种现状,首先要认识到在大学英语教学中导入中国文化的必要性,同时应遵循一定的导入原则,通过教材内容、考核内容的改变及教师文化素养的提升等途径导入和渗透中国文化,从而建立中国文化在大学英语教学中的地位。     

基于LLE算法和SVM的旋转机械故障诊断

利用LLE（Locally Linear Embedding）算法对众多的观测变量进行降维,再利用支持向量分类器SVM（Support Vector Machine）方法对降维后的变量数据集进行故障诊断。通过算例仿真表明,旋转机械故障的23维变量因素可降到14维,同时得到的诊断结果中,训练集的正确率为94．8％,测试集的正确率为100％。结果表明基于LLE算法和SVM的旋转机械故障诊断的模型精度有效。其既降低了模型的复杂度,又不影响故障诊断模型的精度。     

体育文化在高校校园文化中的传承和建设中的作用

大学体育文化是构建大学文化系统的重要分支部分,它既有教育性、健身性、娱乐性和激励性的一些功能,对于大学生的自信、独立、创新、竞争和个人素质及精神上和意识上的培养和提高,都具有很大的促进作用。百年名校体育文化在校园文化中的传承和建设是对中华传统文化的弘扬。     

基于业扩报装的全社会电量预测方法研究

电力系统需求侧业扩报装的容量是分析预测全社会用电量的一个重要参考指标,长期以来,都以定性分析为主,文章以安徽为例,在对相关变量进行季节性分解的基础上,建立业扩报装容量和全省全社会用电量之间的定量关系月度模型。结果表明所建模型预测结果具有较高参考意义,并适用于短期月度电量预测。     

Sol-gel法制备介孔WO3-TiO2复合材料及其光催化性能

以非离子表面活性剂P123为结构导向剂,采用溶胶-凝胶法,通过调整P123与(W+Ti)的摩尔比例,经500℃煅烧制备出一系列不同介孔特性的WO3-TiO2复合光催化材料。利用X射线衍射图谱(XRD)、扫描电子显微镜(SEM)、紫外-可见吸收光谱(UV-Vis)、比表面积分析仪(BET)对复合材料的形貌、孔结构及光谱性质进行表征。研究了介孔WO3-TiO2复合材料对罗丹明B的吸附/光催化降解能力。结果表明,以P123为模板剂所制备的介孔WO3-TiO2复合材料表现出较好的吸附/光催化性能,可见光照射下,0.5g的P123、(W+Ti)摩尔比为0.6%的复合材料经500℃煅烧,对200mL罗丹明B(10mmol/L)的吸附降解率140min后达到97.7%。     

Effects of the radial force on the static contact properties and sealing performance of a radial lip seal

The radial force is a critical factor to determine the sealing performance of radial lip seals.The effects of radial force produced by garter spring and interference on the static contact properties and sealing performance of a radial lip seal are investigated by numerical simulations and experiments.Finite-element analysis and mixed elastohydrodynamic lubrication simulation are used.Radial force,contact width,temperature in the sealing zone,the reverse pumping rate and friction torque are measured.A critical value of interference for a cost-effectively designed radial lip seal is found.Spring force is required to compensate the decrease of the radial force because of the interference and used as a possible way to obtain intelligent control of sealing performance.The quantitative results gotten in this study could provide guide for the seal design and improvement.     

Reduction of nonreciprocal errors in a differential interferometric fiber optical gyroscope using optically differential processing

The bias stability of differential interferometric fiber optical gyroscope is analyzed.Thermal error causing long-term bias drift are reduced by putting the 90°splice in the middle of the fiber coil and applying a wide spectrum light source.Also,a kind of novel optical differential processing,which is much more precise than the electronic differential processing,is proposed for reducing the residual nonreciprocal error in the final differential output.An experimental setup based on optical differential processing was built.An~100 fold reduction in the long-term bias drift is demonstrated experimentally compared with the primary differential interferometric fiber optical gyroscope.     

基于矿物晶体结构的铝土矿细菌浸矿机制研究

采用环状芽孢杆菌CGMCC12对5种含不同结构硅酸盐矿物的铝土矿样进行了生物脱硅研究.选用铝土矿中常见的橄榄石、高岭石、钾长石及河南铝土矿作为细菌溶蚀作用对象,采用电镜及XRD衍射技术,研究细菌对它们的分解作用差异.结果表明:浸矿12d,细菌对橄榄石、高岭石及石英型铝土矿脱硅作用显著,铝硅比(A/S)分别从7.12,6.11,2.89提高到16.15,11.61,13.56,而对钾长石型铝土矿及河南铝土矿脱硅效果较差,A/S分别从3.69和4.90仅提高到4.64和7.30;细菌对试验用硅酸盐矿物的溶蚀破坏作用由易至难依次为橄榄石、高岭石、钾长石;在细菌作用下,橄榄石向水镁石与石英转化,钾长石向伊利石转化,高岭石向水铝石与石英转化;多种矿物同时存在的情况下,细菌对不同晶体结构的硅酸盐矿物的分解有一定的选择性,对较易分解的矿物破坏作用较快,细菌会优先选择分解含Fe,Ca等生命元素的赤铁矿与方解石等矿物.     

Deterioration mechanism of sulfate attack on concrete under freeze-thaw cycles

The experiments of concrete attacked by sulfate solution under freeze-thaw cycles were investigated. The sulfate solution includes two types of 5% Na2SO4 and 5% MgSO4. Through the experiment, microstructural analyses such as SEM, XRD and TGA measurements were performed on the selected samples after freeze-thaw cycles. The corrosion products of the concrete were distinguished and quantitatively compared by the thermal analysis. Besides, the damage mechanism considering the dynamic modulus of elastically of concrete under the coupling effect was also investigated. The experimental results show that, under the action of freeze-thaw cycles and sulfate attack, the main attack products in concrete are ettringite and gypsum. The corrosion products exposed to MgSO4 solution are more than those to Na2SO4 solution. Furthermore, the content of gypsum in concrete is less than that of ettringite in test, and some of gypsum can be observed only after a certain corrosion extent. It is also shown that MgSO4 solution has a promoting effect to the damage of concrete under freeze-thaw cycles. Whereas for Na：SO4 solution, the damage of concrete has restrained before 300 freeze-thaw cycles, but the sulfate attack accelerates the deterioration process in its further test period.