Study on the Components and Performance of GCrlS Bearing Steel Surface by Gas Multi-elements Penetrating

GAS multi-elements penetrating technology is a newsurface hardening technology developed on the basisof carbonitriding technology.It can not only shortenthe production period,but also improve the mechanicalperformances of the parts,such as torsional strength,flexural strength,wear resistance,and fatigue resistance"'.It features low-temperature multi-elementspenetration that the physical chemistry process ofoxidation-reduction generates the active atoms in thepart surface.In the beginning,the …     

Intelligent cooling structure design of "Z-pins like" silicon rods to enhance the ablation resistance of C/C-ZrC-SiC composites above 2500 °C

In order to improve the ablation resistance of C/C-ZrC-SiC composites by reducing the damage of the protective oxide layer, novel "Z-pins like" silicon rods, which were designed and fabricated by liquid phase sintering, were utilised as a dissipative agent. The microstructure evolution and thermal dissipation behaviour were investigated after ablating above 2500 °C for 300 s. After the "Z-pins like" silicon rods were implanted, the anti-ablative property of the C/C-ZrC-SiC composites was drastically improved by the dissipative thermal protection mechanism. The linear ablation rate of the "Z-pins like" silicon rod-reinforced C/C-ZrC-SiC composite was -0.28 μm/s, which is 112.72% lower than the unmodified composite. Additionally, the actual ablative temperature dropped approximately 357 °C, which enabled abundant SiO₂ to remain in the ablation centre. Furthermore, a dense SiO₂-rich oxide layer with a low oxygen diffusion coefficient is formed that covers the entire ablative surface.     

彩色不锈钢生产工艺及其耐蚀性的研究

采用添加了ＣＳ－１添加剂的常规的不锈钢着色液可以生产出彩色不锈钢。所获彩色膜除包括在常规的着色液中可获得的颜色外，还能着出茶色、咖啡色、古铜色等颜色。通过动电位扫描极化曲线等的测量和分析，研究了所得着色膜的耐蚀性能，并解释着色膜经硬化处理后，耐蚀性得到提高的原因。     

Isolation of feeding deterrents against argentine stem weevil from ryegrass infected with the endophyteAcremonium loliae

Infection of ryegrass (Lolium perenne) by an endophytic fungus (Acremonium loliae) confers resistance against the Argentine stem weevil (Listronotus bonariensis). Extracts from ryegrass clones, infected and uninfected withA. loliae, were compared in a feeding choice bioassay, and several fractions were identified which affected stem weevil feeding behavior. One stem weevil feeding deterrent, peramine C₁₂H₁₇N₅O, has been isolated from infected ryegrass and partially characterized as a basic indole derivative. Extracts from culturedA. loliae had no effect on stem weevil feeding behavior nor was peramine detected in the fungal cultures examined. Peramine and the other active substances are hydrophilic in contrast to the lipophilic properties reported for the neurotoxic lolitrems also isolated from ryegrass infected withA. loliae and associated with causing ryegrass staggers disorder in livestock. It is suggested that ryegrass staggers and stem weevil feeding deterrency may arise by different biochemical mechanisms.     

模具材料的硅硼氮共渗

介绍５ＣｒＮｉＭｏ钢模具材料经硅硼氮共渗后，可使其耐磨性得到明显改善。     

Significance of Wood Terpenoids in the Resistance of Scots Pine Provenances Against the Old House Borer, Hylotrupes bajulus, and Brown-Rot Fungus, Coniophora puteana

We tested how terpenoid (i.e., monoterpenes and resin acids) composition and concentration in wood affects resistance against wood-borers and decaying fungi. Scots pine (Pinus sylvestris) wood from nine provenances having variable terpenoid profiles was studied against the old house borer, Hylotrupes bajulus, and the decay fungus, Coniophora puteana. Provenances represented a 1200-km N-S transect from Estonia to northern Finland, but they were all cultivated for 7 years in the same nursery field, in central Finland. Mean relative growth rate (MRGR) of small H. hajulus larvae positively correlated with the total monoterpene concentration of wood, and feeding was associated with high proportion of levopimaric+palustric acid in wood. Provenance did not affect the MRGR of small or big larvae, but big larvae consumed more wood and produced more frass on the northern Ylitornio trees than on the southern Rakvere and Ruokolahti trees. Low beta-pinene and total monoterpene concentration and low beta: alpha-pinene ratio in wood were all associated with a high number of eggs. The most northern Muonio provenance was the most favored as an oviposition site, differing significantly from Saaremaa, Tenhola, and Suomussalmi. Wood from Saaremaa, Tenhola, Ruokolahti, and Suomussalmi provenance was most resistant against decay fungus, differing significantly from that of Kinnula provenance. However, decay resistance was not clearly associated with the concentrations of wood terpenoids. These results suggest that monoterpene composition of wood affects resistance against wood-boring Cerambycid beetles, but resistance against wood-decaying fungi is not as clearly associated with wood terpenoids.     

三聚氰胺改性脲醛树脂粉体胶粘剂的研制

用三聚氰胺改性脲醛树脂改善了胶粘剂的耐沸水性,并有效地降低了游离甲醛含量。三聚氰胺改性脲醛树脂粉体胶粘剂应用更广泛,性能更可靠。     

一种耐超高温、耐酸聚合物的制备及性能测试

摘要：为解决常规聚合物无法满足超高温深井酸化压裂的技术要求，本文分别以丙烯酰胺（AM） 甲基丙烯酰氧乙基三甲基氯化铵（DMC）、AM DMC SMA（十八烷基甲基丙烯酸酯）为原料，通过自由基聚合制备出两种耐酸聚合物SY-1和SY-2，并对其结构进行表征及性能测试。结果表明：SY-2红外谱图中720 cm-1为—(CH2)n—的弯曲振动吸收峰，单体成功接枝到聚丙烯酰胺分子链上；热重分析表明，SY-1升温至600℃失重比为98%，SY-2失重比86%，热稳定性得到改善；质量分数为20%盐酸中，SY-2质量分数0.8%：180℃，170s-1流变性能测试，SY-2剪切终点黏度56mPa?s，90℃、120℃、150℃剪切1h，黏度为83.6mPa?s、43.5mPa?s、27.8mPa?s，剪切稳定性分别为85.66%、74.45%、52.01%； 180℃、3MPa条件下，静态酸岩反应速率为8.94?10-5(g/cm2?s)，较常规SY-1反应速率1.69?10-4(g/cm2?s)减小一个量级。且与缓蚀剂、铁离子稳定剂配伍性良好，克服高温酸化压裂技术的应用瓶颈。     

恒压操作下深层过滤阻力模型的研究

分析了流体在深层滤床中所受的阻力,从经典的达西公式和科泽尼——卡曼方程着手,推导出清洁滤层的过滤阻力及过滤速度表达式,在此基础上结合深层过滤物理模型,引入微元概念,得到恒压操作下截污滤层的过滤阻力和过滤速度数学模型,明确了过滤阻力随各种参数的变化关系,对恒压操作深层过滤的应用有指导意义。     

改性丙-叔共聚乳液在天然石漆生产中的应用

以丙烯酸酯-叔碳酸乙烯酯共聚乳液为基料生产的天然石漆，具有形象逼真、不褪色、耐水耐碱性好、抗紫外线辐射性强等特点。