职业教育课程特点研究综述

对职业教育课程的特点,国内外学者从不同角度给出多种阐释,但都力求逼近职业教育课程特点的本来面貌.以要素比较的方法探讨职业教育课程特点,可以认为其显著特点是应用性、综合性和适用性.     

纵向槽孔板的应力集中系数

根据Ｈｅｌｌｉｎｇｅｒ－Ｒｅｉｓｓｎｅｒ原理，建立了一种具有一个无外力圆形边界的特殊杂交应力元，其应力场准确满足弹性力学平衡方程、协调方程及无外力圆弧上的边界条件。根据修正的Ｈｅｌｌｉｎｇｅｒ－Ｒｅｉｓｓｎｅｒ原理，建立了另一种具有一个无外力直边界的特殊杂交应力元，其应力场在元上变分满足平衡方程，但准确满足无外力直边上的边界条件。数值算例表明：特殊假定应力元与一般假定位移元这两类元联合，能十分有效地进行纵向倒圆槽孔板的应力集中分析。     

古汉语教学中的几个问题

假借、形声是汉字和汉语历史上的两个重要阶段,汉字由此获取表音特点。通假并不避免意义关联,古今字通假是古汉语的事实,也是常规。形声字声符寓义、形声字族具有义通关系．这一观念具有很大的理论和应用价值。联绵词事实上包括了两类词,即单纯的双音词,和词源或结构不明的双音词。     

黑龙江穆棱新生代玄武岩锆石巨晶的微量元素及Hf同位素研究

穆棱古近纪（第三纪）碱性玄武岩位于郯庐断裂东北段分支敦化～密山深大断裂带的中北部,与吉林敦化、汪清,黑龙江镜泊湖、牡丹江等新生代火山岩一起分布于兴蒙造山带和太平洋板块俯冲带结合带上;本文利用电子探针、激光剥蚀等离子质谱技术（LA-ICP-MS）及多接收器电感耦合等离子体质谱仪（MC-ICP-MS）分析了来自玄武岩风化冲积物中锆石巨晶的主、微量元素及其Hf同位素组成.这些锆石巨晶具有明显的熔蚀结构,锆石电子探针分析其Zr/Hf比最高可达217,平均150,是目前东部新生代玄武岩锆石巨晶的最高值.它们具有相似的微量元素特征,具有明显的Ce正异常,富集重稀土和HFSE元素,锆石Hf/Y比值大多小于10,Th/U均小于1（一个数据例外）,Yb/Sm为21～59.与岩浆锆石和变质锆石相比,显示过渡的特征;锆石^176Hf/^177Hf变化为0.283105～0.283151,εHf变化在＋11.8～＋13.4之间,显示亏损地幔来源,反映锆石形成时岩石圈地幔主体具有＂新生＂的特征,表明岩石圈减薄或置换事件在东北地区东北部穆棱地区也同样存在.穆棱新生代碱性玄武岩有关锆石巨晶的成因特征与中国东部海南文昌、福建明溪及山东昌乐等地新生代玄武岩的锆石巨晶相同,可能与有下地壳物质参与的近期岩石圈地幔的交代作用有关.     

Distribution characteristics of minerals and elements in chromite ore processing residue

In this paper,environmental scanning electron microscopy (ESEM) is applied to characterizing the mineral and element distribution of chromite ore processing residue (COPR).The test results show that Cr-bearing brownmillerite occurs in the rim of COPR particle,while hydroandradite with Cr(Ⅵ) in its structure presents inside the COPR particle.Periclase and calcite occur in the interstitial area.Element analyses show that Ca,Fe and Al are distributed throughout the COPR particle,and Mg exists mostly in the interstitial area or on the particle surface.A lower content of Cr is evenly distributed in the COPR particle,while slightly higher concentration of Cr occurs inside the particle.It is suggested that it will take a relatively longer time for Cr to migrate out of COPR,especially for hexavalent chromium,so the leaching time and the particle size may be two important factors to affect the release of Cr(Ⅵ).     

国外母语课程教材管窥

国外母语课程教材具有多样化的类型、体例和相似的表层成分，这些表层成分取决于课程内容的深层要素。从课程研制到课程实施经过了多重转换，其中教材编者对课程内容进行了认真的教学法加工，而这种加工具有其深厚的理论基础。     

N元格蕴涵代数不等式的解^＊ I

在格蕴涵代数中研究了带蕴涵算子的N元格蕴涵代数不等式,得到其有解的充分必要条件,同时还在b是L交既约元的情况下,找出该不等式的所有极小解,进而给出N元格蕴涵代数不等式的具体解集.     

名义压力角对双圆弧齿轮弯曲强度影响的研究

双圆弧齿轮具有优良的啮合特性和工艺特性,且齿形参数的选择具有很大的灵活性。通过C语言、AutoLISP语言编程与ALGORFEAS前处理模块结合,构成了一个参数化的三维几何造型系统,利用该系统建立轮齿的三维有限元分析模型,准确、直观,分析计算了名义压力角参数对轮齿弯曲强度的影响。     

Test and numerical analysis on performance of reinforced concrete segment in subway tunnel

To investigate the mechanical behavior of segmental lining,a three-dimensional numerical analysis and test using three actual segments were used to analyze the effects of axial force and reinforcement ratio on the failure mechanism and ultimate bearing capacity of segmental lining.Both numerical and test results confirmed that the cracking load,yield and ultimate load were strongly influenced by axial force,and it was also proved that the yield and ultimate load would increase with the increase of reinforcement ratio,but the cracking load was almost not affected.The cracking load,yield and ultimate load are about 28.7%,500% and 460% larger due to the effect of axial force respectively.The comparison between numerical calculation and test results showed that the finite element analysis results were in good agreement with the test results.     

Model test and numerical analysis on long-term mechanical properties of stepped reinforced retaining wall

Model tests and numerical analyses of stepped reinforced retaining wall were performed to investigate the effects of rheology of backfill and creep of geogrids on the long-term performance of the structure.The geogrid tensions,soil pressures,wall deformations and foundation pressure were measured during model construction and loading.A visco-elasto-plastic model and an empirical nonlinear visco-elastic model were utilized to simulate the stresses and deformations of geogrid-reinforced earth-retaining wall under long-term loads.By comparing test data with numerical results,it is shown that the foundation pressure distribution is nonlinear,and the lateral constraint of geogrids for backfill can cause a redistribution of foundation pressure.The curve of soil pressure is outside convex at each step initially,and it is close to the distribution for the case of vertical wall subsequently.The variation trend of geogrid tensions at different heights is obtained.Moreover,the failure mechanism and development mode of potential slip surface in retaining wall are proposed.