J-Integral of Interfacial Crack Between Metal-Base Ceramic Coating and Steel

The definition ofJ-integral of interfacial crack was introduced.The three.point bending tests were carried out to obtain the criticaI lOading values when the interfacial crack initiation occurred between coatings and substrates.The finite element analysis(FEA)was adopted to analyze the stress distribution in the specimens and compute the J-integral of the interfaciaI crack between LX88A coating and Chinese 0345 steel.The results showed that the average value of critical J-integral iS 0.70 N/m.which can be taken as the fracture parameter to evaluate the interfaciaI fracture behavior for the three-point bending specimens of LX88A coating/Q345 steel system.     

裂纹尺寸对混凝土断裂韧度的影响

利用断裂力学方法对含有裂纹混凝土试件的断裂韧度进行了研究。通过预制不同裂纹深度的混凝土试件,采用三点弯曲试验方法对含裂纹混凝土梁的断裂韧度进行实验,同时利用ABAQUS软件,采用最大主应力牵引损伤开裂准则与线性软化损伤模型进行数值模拟。结果表明,实验结果和数值模拟比较一致,最大误差不超过15%,当初始缝纹长度为40~120 mm时,起裂断裂韧度KiniIC变化幅度较小,失稳断裂韧度KunIC有明显的减小趋势。     

Experimental study on the interfacial delamination in a thermal barrier coating system at elevated temperatures

The failure mode and adhesion of thermal barrier coating (TBC) 8YSZ (ZrO2+8% (w/w) Y2O3) deposited on NiCoCrAlTaY bond coat by atmospheric plasma spraying were investigated. A grooved modified three-point bending specimen that can generate a single interface crack to facilitate the control of crack growth was adopted for testing, which was conducted at the ambient temperature of 100 °C. The morphology and composition of fractured surfaces were examined by means of a scanning electron microscopy (SEM) and an energy disperse spectroscopy (EDS). Images and spectrum show that cracks are initiated and propagated exclusively within YSZ layer adjacent to top/bond coat interface. The load-displacement curves obtained exhibit similar shapes that indicate two distinct stages in crack initiation and stable crack growth. Finite element analyses were performed to extract the adhesion strength of the TBCs. The delamination toughness of the plasma-sprayed 8YSZ coatings at 100 °C, in terms of critical strain energy release rate Gc, can be reliably obtained from an analytical solution.     

Analytical method for promoting process capability of shock absorption steel

Mechanical properties and low cycle fatigue are two factors that must be considered in developing new type steel for shock absorption. Process capability and process control are significant factors in achieving the purpose of research and development programs. Often-used evaluation methods failed to measure process yield and process centering; so this paper uses Taguchi loss function as basis to establish an evaluation method and the steps for assessing the quality of mechanical properties and process control of an iron and steel manufacturer. The establishment of this method can serve the research and development and manufacturing industry and lay a foundation in enhancing its process control ability to select better manufacturing processes that are more reliable than decision making by using the other commonly used methods.     

织物增强混凝土薄板的高温力学性能与微观界面黏结破坏性分析

研究目的：探讨不同温度和持续时间对织物增强混凝土（TRC）薄板裂缝行为和承载能力的影响。通过微观扫描电镜观测观测,分析纤维编织网与基体混凝土间的界面黏结破坏机理。创新要点：明确了高温后纤维编纵网与基体混凝土之间界向粘结破坏的主要原因。以温度和持时为基本参数,对TRC构件的耐高温性能进行正确评价。研究方法：通过三点弯曲试验（地图3）,对高温后试什的力学件能（见图4、5）进行测试。通过微观扫揣电镜观测（见图8～10）,了解高温下纤维编织网、坏氧树脂及基体混凝土的形态。重要结论：1．环氧树脂任200℃高温作用90min时劣化严重,造成纤维网与基体之间的界血黏结破坏,这是导致试件破坏的主要原因;2．在常温或120℃作用下,掺加聚丙烯（PP）纤维可以较大幅度地提高TRC构件的乐载能力;但在200℃、持续时间较长的高温作用下,PP纤维的掺入对试件的乐载力几乎没有影响。     

Designing Bézier surfaces minimizing the L2-norm of the Gaussian curvature

In freeform surface modelling, developable surfaces have much application value. But, in 3D space, there is not always a regular developable surface which interpolates the given boundary of an arbitrary piecewise smooth closed curve. In this paper, tensor product Bézier surfaces interpolating the closed curves are determined and the resulting surface is a minimum of the functional defined by the L2-integral norm of the Gaussian curvature. The Gaussian curvature of the surfaces is minimized by the method of solving nonlinear optimization problems. An improved approach trust-region form method is proposed. A simple application example is also given.     

塑性变形后碳钢扭转疲劳极限与弯曲疲劳极限的关系

应用疲劳试验机对退火后15号和45号碳钢及其各自3种塑性变形材料进行了回转弯曲及扭转疲劳实验,讨论了在相同塑性变量的条件下,两种钢材的扭转疲劳极限与回转弯曲疲劳极限之间的关系。实验结果表明：15号和45号钢的扭转与弯曲疲劳极限的比,分别为0．53～0．57和0．57～0．58,即塑性变量相同的情况下,含碳量高的材料其疲劳极限比也较高;相同含碳量的情况下,塑性变形量较小时其疲劳极限比较低。     

Seymour Benzer and T4 <Emphasis Type="Italic">r</Emphasis>II

One of the goals of genetics is to understand genes in as much detail as possible. For instance, with respect to a given gene, one would like to know its chromosomal location, its physical and genetic size, its neighbours, the number of mutations/alleles defining the gene, the order of mutations, the genetic/physical distance between them, etc. Thus, rather than focusing on the whole genome, one focuses on the finer details of a given genetic segment. The exercise of probing such details is called ‘fine structure genetic analysis’. There are several pioneers who have contributed enormously to this area in many bacterial and phage systems. Two stalwarts, Seymour Benzer and Charles Yanofsky, stand preeminent among them. In the following pages I present briefly Benzer’s outstanding work on the fine structure of the rII region of bacteriopage T4. These path-breaking studies contributed significantly to our understanding of the structure, organization and function of genes. R Jayaraman is an Emeritus Professor of Molecular Biology at the School of Biological Sciences, Madurai Kamaraj University, Madurai, where he taught and carried out research in the area of microbial genetics for three decades.     

Production of bacterial blight resistant lines from somatic hybridization between Oryza sativa L. and Oryza meyeriana L.

Novel bacterial blight (BB) resistance gene(s) for rice was (were) introduced into a cultivated japonica rice variety Oryza sativa (cv. 8411), via somatic hybridization using the wild rice Oryza meyeriana as the donor of the resistance gene(s). Twenty-nine progenies of somatically hybridized plants were obtained. Seven somatically hybridized plants and their parents were used for AFLP (amplified fragment length polymorphism) analysis using 8 primer pairs. Results confirmed that these plants were somatic hybrids containing the characteristic bands of both parents. The morphology of the regenerated rice showed characters of both O. sativa and O. meyeriana. Two somatic hybrids showed highest BB resistance and the other 8 plants showed moderate resistance. The new germplasms with highest resistance have been used in the rice breeding program for the improvement of bacterial blight resistance. Project (No. 98001) supported by Ningbo Agriculture Key Scientific Research Foundation, China     

Evaluation of the dust and methanol extracts of Garcinia kolae for the control of Callosobruchus maculatus (F.) and Sitophilus zeamais (Mots)

Insecticidal effects of different doses of the dust and methanol extracts of Garcinia kolae on Collosobruchus maculatus and Sitophilus zeamais were tested. The dust had no significant effect on the two insects; none of them died even at 3 d after treatment. The methanol extracts, however, had rapid lethal effects on both C. maculatus and S. zeamais. The mortality of C. maculatus by the lowest concentration of methanol extracts ranged from 95%∼100% whereas in S. zeamais, the mortality ranged from 87.5%∼100% and 70%∼100% in concentrations of 1 g extract+3 ml methanol and 1 g extract+5 ml methanol, respectively, from 24 to 48 h. The least concentration of 1 g extract+15 ml methanol had no significant lethal effect on Sitophilus zeamais.      

《实践论》与《矛盾论》的当代价值

《实践论》和《矛盾论》是面向中国问题的哲学,是毛泽东哲学思想的两篇核心著作,开创了马克思主义中国化的先河,在实践基础上产生了马克思主义中国化的第一次飞跃——毛泽东思想,进而指导中国革命、建设和改革,取得了一次又一次的重大胜利。时至当今,《实践论》和《矛盾论》所蕴含的马克思主义哲学立场、观点和方法仍具有十分重要的价值。     

《宝剑记》对《水浒传》的继承与创新

《宝剑记》主要取材于我国古典小说《水浒传》中"林冲落草"这段故事。相较来看,《宝剑记》继承了《水浒传》的很多方面,包括主要人物设置,故事情节内容,"忠奸"主题思想。除此,《宝剑记》在人物形象、情节脉络、中心矛盾、起因结局等方面又有所创新。《宝剑记》对《水浒传》的改编凸显出明中叶反封建专制统治的社会思潮和人的自我意识的觉醒,也是作者李开先个人心灵世界的直接映现,具有明显的进步性与现实意义。     

Relationship between teacher intentions and their classroom use of Superscience

Using the conceptual model of reasoned action, one would expect that what teachers do with instructional materials would be influenced by their internal beliefs and their external constraints. In this two-year study with elementary teachers, using a supplemental science instructional resource,Superscience, it was found that teachers' internal beliefs about what will benefit their students are linked to the external constraints of their students' interests and the expected curriculum. Even if the teachers believed that the content of the resource would be helpful, they were not likely to use it if they believed it did not fit the expected curriculum.     

恶之花——《洛丽塔》的亨伯特与《黑暗之地》的阿尔比恩之比较

尖锐形式的恶是文学的表现。《洛丽塔》与《黑暗之地》这两部小说都用第一人称诚实地交流表达出对恶的严格道德上的认识,其中的主人公都涉及父女乱伦与强奸,在怪癖、丑陋的变态与病态空间里讨论人们尚不熟悉的恶的美学,表达了作者不同的创作主题。纳博科夫通过亨伯特与洛丽塔之间的畸形恋情描写探索了伦理道德世界的复杂人性;格伦维尔创造阿尔比恩的恶的形象充分说明了男权话语霸权对男女双方造成的身心伤害。     

王充与王莽非同宗考

黄晖等人指出王充、王莽均有孙、王二姓,且同出魏郡元城,乃是同族,然细考《汉书·元后传》《论衡·自纪篇》之记载,详玩汉人传记的通行文法,此说难以成立。诸般史迹表明,王充、王莽分属两个平行发展的独立家族,绝非同宗。王莽的宗姓在东汉一朝备受猜忌,王充对王莽之行事素无好感,《论衡·自纪篇》交待"其先本魏郡元城一姓"仅是陈述事实,并无攀附王莽之意。     

Relationships between changes of kernel nutritive components and seed vigor during development stages of F1 seeds of sh 2 sweet corn

The changes of kernel nutritive components and seed vigor in F₁ seeds of sh ₂ sweet corn during seed development stage were investigated and the relationships between them were analyzed by time series regression (TSR) analysis. The results show that total soluble sugar and reducing sugar contents gradually declined, while starch and soluble protein contents increased throughout the seed development stages. Germination percentage, energy of germination, germination index and vigor index gradually increased along with seed development and reached the highest levels at 38 d after pollination (DAP). The TSR showed that, during 14 to 42 DAP, total soluble sugar content was independent of the vigor parameters determined in present experiment, while the reducing sugar content had a significant effect on seed vigor. TSR equations between seed reducing sugar and seed vigor were also developed. There were negative correlations between the seed reducing sugar content and the germination percentage, energy of germination, germination index and vigor index, respectively. It is suggested that the seed germination, energy of germination, germination index and vigor index could be predicted by the content of reducing sugar in sweet corn seeds during seed development stages. Project supported by the National Natural Science Foundation of China (No. 30370911) and Education Department of Zhejiang Province, China (No. 20070147)     

李大钊《我的马克思主义观》新探——兼谈《新青年》第6卷各号的出版时间

《我的马克思主义观》是李大钊成为马克思主义者的标志,是五四新文化运动的重要转折点,也是马克思主义在中国开始广泛传播的重要标志。有关论著对它的研究和提及很多,《李大钊全集》的编注者对其注解也较多。进一步研究起来,该文中需要探究的问题仍有不少。总起来看,李大钊的《我的马克思主义观》以日本社会主义学者河上肇的《马克思的社会主义理论体系》为重要蓝本,其关于马克思主义三个组成部分与一条“金线”的核心论断也出于河上肇此文;写作和定稿时间,应为1919年7月底到8月上旬,而不可能在1919年5月之前。     

Microbial control of diamondback moth,Plutella xylostella L. (Lepidoptera: Yponomeutidae) using bacteria (Xenorhabdus nematophila) and its metabolites from the entomopathogenic nematode Steinernema carpocapsae

Cells and cell-free solutions of the culture filtrate of the bacterial symbiont, Xenorhabdus nematophila taken from the entomopathogenic nematode Steinernema carpocapsae in aqueous broth suspensions were lethal to larvae of the diamondback moth Plutella xylostella. Their application on leaves of Chinese cabbage indicated that the cells can penetrate into the insects in the absence of the nematode vector. Cell-free solutions containing metabolites were also proved as effective as bacterial cells suspension. The application of aqueous suspensions of cells of X. nematophila or solutions containing its toxic metabolites to the leaves represents a possible new strategy for controlling insect pests on foliage.     

<Emphasis Type="Italic">Agrobacterium</Emphasis>-mediated transformation of herbicide resistance in creeping bentgrass and colonial bentgrass

Embryogenic calli were induced from the seeds of creeping bentgrass (Agrostis palustris Huds.) cv. Regent and colonial bentgrass (Agrostis Tenuis Sibth. Fl. Oxen.) cv. Tiger. The embryogenic calli were precultured on fresh medium for 4–7 days and then co-cultivated withAgrobacterium tumefaciens, LBA4404. which contains plasmid vector-pSBGM harboring bar coding region, synthetic green fluorescent protein (sGFP) coding region and matrix attachment region (MAR). After 3 days of co-cultivation, the calli were washed thoroughly and transferred to MS medium containing 2 mg/L of 2, 4-D, 12–15 mg/L phosphinothricin (PPT) and 250 mg/L of cefotaxime. After 2–3 months of selection, the actively growing calli of ‘Regent’ and ‘Tiger’ were transferred to MS medium with 12–15 mg/L PPT and 250 mg/L cefotazime for regeneration. The putative transformants were maintained on MS medium with 3 mg/L PPT for long period but control died within 1 month. After establishing in greenhouse, the transformants also showed strong resistance to 0.4% of herbicide Basta but control plants died within 2 weeks. Under confocal microscope, both young leaves and roots showed significant GFP expression. PCR analysis revealed the presence of a DNA fragment of GFP gene at the expected size (380 bp) in the transformants and its absence in a randomly selected control plant.