FATIGUE CRACK GROWTH BEHAVIOR of 0Cr18Ni9 STAINLESS STEEL AT HIGH TEMPERATURES

研究奥氏体不锈钢0Cr18nI9在高温(550℃)下的疲劳裂纹扩展规律。测试采用标准CT(COMPACT TEnSIOn)试样,最大载荷范围为6.5 kn~14 kn,应力比为0.1(室温)和0.05(550℃)。裂纹扩展过程通过QuESTAr长焦距显微镜直接观测,同时采用COd(CrACk OPEnIng dISPlACEMEnT)规记录加载线位移。由于在高温条件下,测试终止时试样的裂纹前缘呈明显弧形,故此给出实测表面处裂纹长度有效值的修正方法。对高温疲劳裂纹扩展问题,采用应力强度因子范围Δk作为裂纹扩展驱动力参数,同时考虑高Δk和低Δk值对裂纹扩展规律的影响,得到0Cr18nI9不锈钢在550℃下的疲劳裂纹扩展规律表征模型,给出裂纹扩展率的上限结果。For austenitic stainless steel 0Cr18Ni9,fatigue crack grow law are studied at 550 ℃.The crack growth tests adopt the standard compact tension(CT) specimens.The applied maximum loads are from 6.5 kN to 14 kN and the stress ratios are 0.1(at room temperature) and 0.05(at 550 ℃).The crack growth length is directly measured by QUESTAR long focus microscope system and the load-line displacement is simultaneously recorded by using crack opening displacement(COD) gauge.Because of the good ductility of 0Cr18Ni9 at high temperatures,the crack front curves on fracture surface of the specimens are complex.In order to get an effective crack size,a modified method for crack length inspected on the surface is proposed.The stress intensity factor range ΔK is used as the driving force parameter of fatigue crack growth.Considering the high ΔK and the low ΔK effects on the fatigue crack growth law,the fatigue crack growth law is obtained for stainless steel 0Cr18Ni9 at room and high temperatures and the upper bound to the crack growth rate is given.国家自然科学基金(50605039);福建省新世纪优秀人才支持计划资助项目---

Improvement of shortest path ray tracing method

综述了用网络最短路径算法求解地震射线追踪问题的原理、方法技术以及存在问题和改进措施 .特别介绍了作者在最短路径算法基础上 ,提出的动态网络最短路径地震射线追踪方法 .该方法先采集从炮点到整个模型所有节点上的初至旅行时 ,其中 ,在一个单元内 ,对相邻每对已计算出最小旅行时的节点进行线性插值 ,并利用Fermat原理计算未知节点的最小旅行时 ;然后 ,利用同样的方法 ,从接收点开始 ,反向追踪炮点到接收点的射线路径 .该方法能适于各种复杂的非均匀介质 ,极大地提高了射线追踪的精度 .The principle and method of seismic raytracing with shortest path algorithm in networks are discussed, the relevant drawbacks in which and improved measures are also analyzed. Especially, we develop a shortest path raytracing method with dynamic networks based on the shortest path algorithm. The wavefront times are sampled at the nodes away from the source throughout the entire model. The first arrival times at nodes in a cell are expressed with linear interpolation between traveltimes obtained aforehand at each pair of two neighboring nodes, and then determined by Fermat principle. After the first arrival times being sampled throughout the model, the raypaths from the source to each receiver are obtained backward away from the receiver to source in the same way as the forward sampling. This algorithm is regardless of model complexity, and has a higher precision for computation of seismic traveltimes and raypaths

Developing fast laboratory screening platform for sulfate dioxide in food by surface-enhanced Raman spectroscopy

基于表面增强拉曼光谱(SERS)的指纹图谱的高能量分辨率,以位于~630; cm~(-1)亚硫酸根的特征峰为定性和定量依据,本文开展了食品中滥用和非法添加二氧化硫的直接检测研究:一种检测流程实现了不同食品基质中二氧化硫的; 高灵敏检测,最低检出浓度达1 mg; kg~(-1)的水平.针对实际样本的传统蒸馏法前处理流程的一些不足以及SERS检测的指纹图谱优势,本文进行了三方面显著改进:; (1)碳酸钙和沸石取代氮气以提高二氧化硫的挥发提取效率; (2)草酸取代盐酸酸化蒸馏溶液,以有效避免挥发性强酸对操作环境的危害;; (3)氢氧化钠溶液代替乙酸铅溶液作为吸收液,以防止二次污染.环境友好、灵敏度高和不受基质干扰等特点使得本方法有望取代经典蒸馏法和比色法,用于食品; 中非法添加二氧化硫类添加剂的快速高效筛查.The direct detection of sulphur dioxide has been realized in various; food matrixes with high sensitivity and high selectivity, on the basis; of the integration of the high energy resolution of the finger-print; spectrum of surface-enhanced Raman spectroscopy and the universal but; easy-on-going pretreatment procedure. The characteristic peak of sulphur; dioxide at ~630 cm~(-1) was applied as the qualitative and quantitative; standard, which displayed a lowest detectable concentration at the 1 mg; kg~(-1) level for the spiked food samples. The key point of the high; sensitivity and selectivity is the effective pretreatment born out of; the standard distillation one, which has been improved in the three; parts. (1) Using CaCO_3 and Zeolite instead of N_2 gas as the bubbling; reagent. (2) Using oxalic acid as the acidic distillation solution to; eliminate the hazards from acid volatilization, such as hydrochloric; acid. (3) Using diluted sodium hydroxide solution as the absorption; reagent instead of lead acetate solution to avoid the secondary; pollution. With the three distinguished advantages of environment; friendly, high sensitivity and free of matrix interference, the proposed; method has great potential to replace the traditional ones for the fast; screening of the illegal or abused sulphur dioxide in food.国家自然科学基金; 福建省高校产学合作项目; 中央高校基本科研业务费专项资

Relationship Between SHG EFFect and Crystal Structure in Complexes of Sub-Group Metal Halide and POM

已发现某些金属有机配合物是一类有前景的非线性光学材料，为了系统地探索二次谐波发生（SHg）效应大、综合性能好的新型金属有机配合物非线性光学晶体材料，则有必要探讨它们的性能与结构之间的关系。考虑到某些具有较大二阶极化率的有机分子可能与副族金属卤化物形成配合物，于是对这些配合物的二次谐波效应与晶体结构的关系进行了较系统的研究，发现它们实测的SHg强度的大小与晶体的配位键中离子键和共价键成分的大小相一致。Some organometallic complexes which are a type of potential nonlinear optical materials have been discovered.In order to make a systematic exploration For new organometallic complexes exhibiting large second harmonic generation(SHG)eFFect and good comprehensive properties ,it is necessary to study the relationship between the property and the structure.Considering the possibility of Forming complexes between some organic molecular crystals exhibiting good SHG eFFect and metallic ions of the sub-group,the relationship between the second-harmonic eFFect and the crystal struture of these complexes was investigated systematically.The experimentation discovered that the regularity of their SHG intensity agree with the regularity of the crystal structure.国家自然科学基金、福建省自然科学基

Level Statistics for the Nilsson Single-Particle Levels

National Natural Science Foundation of China [10605018, 10975116, 10675170]; Program for New Century Excellent Talents in University [NCET-07-0730]; National Basic Research Program of Chin [2007CB815003]We perform level statistics of the Nilsson single-particle levels. The effects of the l(2) and l . s terms are discussed as well as their interplay with the deformations. The results show that when the l(2) term is added to the harmonic oscillator potential, chaotic motion occurs. The strength ranges of the l(2) term in which chaotic motion exists are related to the deformation of the harmonic oscillator potential. The calculations of the localization length in different bases demonstrate that it is the spherical or axial symmetries that govern the chaotic motion. The degree of chaoticity increases significantly with the l . s term included

中国高等教育70年十人谈(笔会)

70年来我国高等教育发展在国家层面的思想上体现出从以政治建设为中心到以经济建设为中心,最终指向以人民为中心的特征;在大学和政府关系上表现为自主性从失落到逐渐回归;在高校内部管理模式上从管理向治理转变。吸取70年的经验教训,未来我国高等教育改革发展需注意以下方面:走出计划经济与市场经济的双重藩篱,提升自身的成熟度和主体性;扎根中国大地,推动中国高等教育优秀文化传统的现代转换和创新性发展;加快推进大学校长专业化进程,实现"教育家办学";继续探索较为理想和具有示范效应的院系设置模式;在"双一流"建设背景下,还要支持和鼓励地方高水平大学的发展,注意淡化"排名"和"一流"在政策目标中的重要性,最终实现高等教育内涵式发展。中宣部文化名家暨“四个一批”人才自选项目(中宣干字[2016]133号)的阶段性研究成果教育部哲学社会科学研究重大课题攻关项目“高校内部治理体系创新的理论与实践研究”(项目编号:16JZD039)的阶段性成果;教育部哲学社会科学研究重大课题攻关项目“博士研究生教育体制机制改革研究”(项目编号:17JZD057)的阶段性研究成果;教育部人文社会科学研究一般项目“高校所属学院的重要事项决策权配置及其整合机制研究”(项目编号:15YJA8800)的阶段性研究成果江苏高校哲学社会科学研究重大项目“地方统筹与高等教育治理”(项目编号:2019SJZDA082)的阶段性研究成

Experimental study on reperfusion of intraocular lens

作者简介: 祁明信, 男, 1945 年7 月 出生, 教授、主任医师、博士研究生 导师, 主要从事白内障的基础与临 床研究。联系电话: 0591-83570887; E-mail:qihuang@netease. com 通讯作者: 黄秀榕,E-mail:[email protected][中文文摘]目的开展晶状体再灌注的离体和动物实验研究,并对再灌注人工晶状体技术进行评价。方法采用新鲜离体幼兔眼、离体猪眼、新西兰白兔眼,应用自行研制的人工晶状体材料,进行以下实验:(1)体外固化实验;(2)晶状体前囊膜微型撕囊及其稳固性实验;(3)经微型前囊膜开口超声乳化吸出晶状体内容物实验;(4)活的新西兰白兔眼内人工晶状体再灌注实验。结果(1)按硅酮聚合物与固化剂50:1的比例可获得柔软、弹性好、固化时间短(完全固化时间为60min)的注入材料;(2)晶状体前囊膜1.8～2.0mm的连续环形撕囊口具有较好的稳定性,可经该微型开口吸出晶状体内容物并灌注材料;(3)超声能量18%、流量25mL·min-1、负压120mmHg(1kPa=7.5mmHg)为晶状体内容物经微型前囊膜开口吸出的最佳条件;(4)注入灌注材料后可形成由晶状体囊膜包裹的、置换原晶状体皮质和核的、新的再灌注人工晶状体。结论采用再灌注人工晶状体的方法可进行新型人工晶状体再灌注,可为治疗白内障和老视提供参考。[英文文摘]Objective To carry out the experimental study on reperfusion of intraocular lens(IOLs) in vitro or in animal,and to assess the technique of IOLs reperfusion.Methods The following experiments were performed by using self-developed materials in fresh rabbit eyes and pig eyes in vitro,as well as in eyes of alive New-Zea-land rabbits:(1)Solidification study of self-developed material in vitro;(2)Continuous circular capsulorhexis(CCC) in anterior capsule of lens and its stability;(3)Draw of lens contents via phaco through mini-CCC;(4)IOLs ref illing in the eyes of alive New-Zea land rabbits. Results(1) Thematerialwhich was soft, springy and short-term solidification(full solidification time was 60 minutes) were obtained in certain proportion of geland solidified agent(50:1) in vitro; ( 2)The CCC in anterior capsule of lens with 1.8-2.0 mm diameter had very good stability. The lens contents were drawn and the materialwere refilled through themini-CCC; (3) The best conditions of drawing out lens contents through m ini-CCC were phaco energy 18% , flow 25 mL·min- 1, and negative pressure 120 mmH g (1kPa=7.5 mmHg);(4) The new refilled IOLs, which were wrapped by capsule of lens and were replaced original cortex and nucleus of lens, were obtained after thematerial refillied. Conc lusion. New IOLs are refilled through this method, which can prov ide reference for the treatment of cataract and presbyopia.福建省科技三项费用;教育厅重点资助项目基金资助(编号:K98041

中国式学科评估:问题与出路

今年四月份,教育部学位与研究生教育发展中心(以下简称"教育部学位中心")邀请全国学位授予单位参加全国第四轮一级学科整体水平评估。随之,各个高校展开了一场大规模、高级别的学科评估申报及材料提交总动员。第四轮学科评估自发布起也引发了学界的广泛关注和热烈讨论。高等教育是中国崛起的思想发动机,关涉民族复兴的未来,而学科评估是近年来中国高等教育学科建设成就的集中展示,其意义和影响可谓深远。为了更好推进学科评估科学进行,特别是促进高等教育健康发展,《探索与争鸣》编辑部邀请全国

HYDROLOGICAL OBSERVATION IN AN EVERGREEN BROAD LEAVED FOREST IN THE WUYI MOUNTAINS

[中文文摘]对武夷山甜槠林成熟林水文学效应的研究结果表明：观测期间，年大气降水量2678.78ｍｍ，林内雨量2182.04ｍｍ，林冠截留量为496.74ｍｍ；林内雨中，穿透雨量2082.08ｍｍ，树干茎流99.96ｍｍ；到达甜槠林地作用面的林内雨量中，被地表枯枝落叶层截留的雨量为159.84ｍｍ，地表径流量11.6ｍｍ，地下渗流量109.32ｍｍ，其余林内雨量形成土壤含水量增量并由地表物理蒸发、根系吸收以及植物蒸腾所消耗；甜槠林地o~20０ｃｍ土层水分初渗率78.6ｍｍ·ｍｉｎ－１，稳渗率１５．５ｍｍ·ｍｉｎ－１，达到稳渗历时４５ｍｉｎ，地表枯枝落叶最大持水量5.2ｍｍ，土壤蓄水量154.0ｍｍ。与国内其它地区不同类型的森林相比较，武夷山甜槠林具有较强的水文学效能。[英文文摘]Hydrological observations were made in a 76 year old Castanopsis eyrei forest of the Wuyi Mountains.The results are as follows:(1)In the study period during 1993～1994,annual gross precipitation,net precipitation (throughfall was 208204mm and stemflow was 9996mm)and interception loss were 267878mm,218204mm and 49674mm respectively.Interception rate was 1845%.(2)Net precipitation,the part of gross precipitation appearing on the forest floor,was redistributed through different routes.The part absorbed by litter layer was an annual amount of 15984mm,and accounting for 733%.The parts as surface runoff and below ground drainage were annual amounts of 116mm and 10932mm respectively,and accounting for0.53% and 5.01%,respectively.The rest was kept in soil and then lost to the atmosphere by means of ground physical evaporation or plant transpiration as absorbed by the roots.Its amount was 190128mm,and accounting for 87.13%.(3) The initial infiltration rate and stable infiltration rate for the soil layer of 0～20cm were 786mm·min-1 and 155mm·min-1 respectively.The time needed to arrive at the stable state was 45min.Water storage capacity of soil was 15041t·hm-2.The maximum water holding capacity of litter layer was 52mm.福建省自然科学基金,武夷山自然保护区管理局资