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光学学报 1999年第8期19卷 1118-1120页

作者：唐志列梁瑞生朱小松何振江司徒达华南师范大学物理系广州510631

讨论了共焦扫描激光显微镜的纵向分辩率和信噪比对三维成像能力的影响，给出了纵向分辨率极限的判据，

关键词：偏振共焦显微镜纵向分辨率成像激光显微镜

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飞机外表面清洗剂AHc-1的研制

材料工程 1999年第3期27卷 28-31页

作者：李斌张晓云司徒振民北京航空材料研究院

针对飞机表面材料及油污特点研制的飞机外表面清洗剂ＡＨＣ－１，主要技术指标达到了美军标ＭＩＬ－Ｃ－８５５７０Ｂ《飞机外表面清洗化合物》（Ⅱ型）的要求，是一种安全、高效、环保型的水基清洗剂。

关键词：飞机清洗剂技术指标缓蚀剂

环氧豆油/酚醛交联树脂的制备和抗吸水机理研究

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高校化学工程学报 2011年第1期25卷 103-108页

作者：司徒粤胡剑峰周利庄陈焕钦华南理工大学化学与化工学院广东广州510640

通过苯酚羟基醚化和环氧豆油(ESO)扩链聚合制备了环氧豆油/酚醛(PR)交联树脂,采用扫描电子显微镜和热分析分别研究了醚化和扩链对改性酚醛树脂微观形貌及抗吸水性的影响。ESO扩链聚合物与酚醛树脂不相容,通过醚化反应可改善相容性并接... 详细信息

通过苯酚羟基醚化和环氧豆油(ESO)扩链聚合制备了环氧豆油/酚醛(PR)交联树脂,采用扫描电子显微镜和热分析分别研究了醚化和扩链对改性酚醛树脂微观形貌及抗吸水性的影响。ESO扩链聚合物与酚醛树脂不相容,通过醚化反应可改善相容性并接枝形成软硬链段交联网络。ESO与酚醛交联聚合能够增强树脂的抗吸水性,由该交联树脂制得的纸层压板吸水率可降至0.13%,其抗吸水机理包括对极性酚羟基的醚化封闭和疏水链段屏蔽作用。醚化接枝确保疏水柔性链在酚羟基区域均匀分布,扩链过程可增大疏水链段空间位阻,两者相互结合实现屏蔽作用最大化和抗吸水性最优化。

关键词：环氧豆油酚醛树脂抗吸水性交联

Determination of surface structure and the depth profile of silica glass by infrared spectroscopy

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光学精密工程 2005年第4期13卷 413-420页

作者： c. Z. Tan Laboratory of Solid State Microstructure and Department of Materials Science and Engineering Nanjing University 210093 Nanjing China Institut für Mineralogie Freie Universitt Berlin 14195 Berlin Germany

The surface structure and properties are different from those of the bulk, depending on the substrate materials and deposition condition, and playing an important role in precise optical components. The conventional spectroscopic methods to monitor the surface structure are restricted only in several layers of molecules. It is known that the penetration depth of the incident light increases with its wavelength and decreases with the angle of incidence. Thus infrared spectroscopy provides a powerful means for determination of surface structure and the depth profile up to micrometers. By recording the reflection spectra at different angles of incidence, the surface structure and its depth profile can be monitored successively. Further, the incident field has the subcomponents parallel and perpendicular to the surface, which excite the transverse and longitudinal optic modes, respectively. change of the polarization direction of the incident light provides a practical function to study anisotropic property of the surface and the interaction between the transverse and longitudinal optic modes. In this work, infrared spectrophotometer was applied to investigate the depth profile in microstructure of silica glass. combining with the glass fiber system, this technique can be used for in-situ control of the deposition process. In comparing with ellipsometry, this method reveals both structural and constitutional information.

关键词：硅石光谱红外线表面结构光学材料

舒芬太尼超前镇痛联合颈丛神经阻滞用于甲状腺瘤切除术的有效性和安全性

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中国实用医药 2017年第5期12卷 6-9页

作者：司徒颖芬开平市第二人民医院麻醉科 529367

目的对舒芬太尼超前镇痛联合颈丛神经阻滞在甲状腺瘤切除术中的临床效果及安全性进行探究。方法 120例接受甲状腺瘤切除术治疗的患者为研究对象,依据麻醉方式的不同分为A组(单纯颈丛神经阻滞)、B组(舒芬太尼术中应用联合颈丛神经阻滞)以... 详细信息

目的对舒芬太尼超前镇痛联合颈丛神经阻滞在甲状腺瘤切除术中的临床效果及安全性进行探究。方法 120例接受甲状腺瘤切除术治疗的患者为研究对象,依据麻醉方式的不同分为A组(单纯颈丛神经阻滞)、B组(舒芬太尼术中应用联合颈丛神经阻滞)以及c组(舒芬太尼超前镇痛联合颈丛神经阻滞),各40例。对三组患者的麻醉效果、Ramsay镇静评分进行对比,观察比较三组颈丛阻滞前(Tl)、切皮后5 min(T2)、剥离瘤体时(T3)、术毕时(T4)的平均动脉压(MAP)、心率(HR)、血氧饱和度(Sp O2)差异。结果 A、B、c组麻醉优良率分别为75.0%、80.0%、100.0%,c组优良率明显优于A组、B组,差异均具有统计学意义(P0.05)。c组Ramsay评分效果明显优于A组、B组,差异均具有统计学意义(P0.05)。c组T2、T3、T4时的HR及MAP均优于A组、B组,差异均具有统计学意义(P0.05)。三组SpO_2变化不明显,组间比较差异无统计学意义(P>0.05)。结论对于行甲状腺瘤切除术的患者采取舒芬太尼超前镇痛联合颈丛神经阻滞能够有效提升患者麻醉效果,提升手术安全性与舒适度,值得推广。

关键词：甲状腺瘤颈丛神经阻滞切除术麻醉效果 Ramsay镇静评分

Improving high-temperature mechanical properties of cast crFecoNi high-entropy alloy by highly thermostable in-situ precipitated carbides

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Journal of Materials Science & Technology 2021年第13期72卷 29-38页

作者： X.w.Liu N.Gao J.Zheng Y.wu Y.Y.Zhao Q.chen w.Zhou S.Z.Pu w.M.Jiang Z.T.Fan State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430074China Institute of Nuclear Physics and chemistry China Academy of Engineering PhysicsMianyang 621999China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China School of Materials Engineering Purdue UniversityWest LafayetteIN 47907USA Southwest Technology and Engineering Research Institute Chongqing 400039China center for Electron Microscopy Wuhan UniversityWuhan 430072China

The cr Fe co Ni high-entropy alloy(HEA)exhibits excellent mechanical properties at lower temperatures due to its low stacking-fault energy,however,its medium-and high-temperature strengths are still *** consideration of the potential diversified applications,more strengthening approaches except for the previously proposed L12 phase hardening deserve further exploration due to its rapid coarsening tendency at high ***,we achieved significant high-temperature strengthening of the cast cr Fe co Ni HEA by in-situ precipitation of highly thermostable *** with 0.5 at.%and 1 at.%niobium and carbon were prepared by simple casting processes,*** cast,solute solution and aging.A highly thermostable microstructure was formed,which comprises very coarse grains accompanied with extensive thermostable carbide precipitates embedded,including submicrometer coherent Nb c particles in grain interiors and intergranular coherent M_(23)c_(6)*** high thermostability of microstructure,which is beneficial for the high-temperature loading,is ascribed to the synergy of lacking growth driving force and Zenner pinning effect by the *** properties tested at 673,873 and1073 K show that the yield strength and ultimate tensile strength are significantly increased by Nb/c doping,along with the elongation escalation at higher *** strengthening is mainly due to the precipitation hardening of carbide particles.

关键词： High-entropy alloy carbides Precipitation High-temperature property Strengthening

芳香多元胺扩链ESO/PR交联树脂的制备与性能

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高分子材料科学与工程 2011年第4期27卷 128-131页

作者：司徒粤胡剑峰徐丽周利庄陈焕钦华南理工大学化学与化工学院广东广州510640 郑州大学化工与能源学院河南郑州450001

采用复合型芳香多元胺扩链剂制备韧性和耐热性好的环氧豆油/酚醛树脂交联聚合物(ESO-c-PR)。研究了ESO含量对ESO-c-PR冲击韧性、弯曲强度、拉伸强度与断裂伸长率的影响,采用差示扫描量热法(DSc),热重法(TG)分析交联体系的热稳定性,用扫... 详细信息

采用复合型芳香多元胺扩链剂制备韧性和耐热性好的环氧豆油/酚醛树脂交联聚合物(ESO-c-PR)。研究了ESO含量对ESO-c-PR冲击韧性、弯曲强度、拉伸强度与断裂伸长率的影响,采用差示扫描量热法(DSc),热重法(TG)分析交联体系的热稳定性,用扫描电镜(SEM)观察了材料断面的形态结构,探讨了增韧机理。结果表明,随着体系中ESO比例的增加,交联树脂的冲击韧性、拉伸强度和断裂伸长率都显著提高,ESO含量为40%时,树脂的综合力学性能最佳。

关键词：芳香多元胺扩链剂环氧豆油酚醛树脂交联

Principles of rockbolting design

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Journal of Rock Mechanics and Geotechnical Engineering 2017年第3期9卷 14-32页

作者： charlie c. Li Department of Geoscience and Petroleum The Norwegian University of Science and Technology Norway

This article introduces the principles of underground rockbolting *** items discussed include underground loading conditions,natural pressure zone around an underground opening,design methodologies,selection of rockbolt types,determination of bolt length and spacing,factor of safety,and compatibility between support *** types of rockbolting used in engineering practise are also *** traditional principle of selecting strong rockbolts is valid only in conditions of low in situ stresses in the rock ***-absorbing rockbolts are preferred in the case of high in situ stresses.A natural pressure arch is formed in the rock at a certain distance behind the tunnel *** should be long enough to reach the natural pressure arch when the failure zone is *** bolt length should be at least 1 m beyond the failure *** the case of a vast failure zone,tightly spaced short rockbolts are installed to establish an artificial pressure arch within the failure zone and long cables are anchored on the natural pressure *** this case,the rockbolts are usually less than 3 m long in mine drifts,but can be up to 7 m in large-scale rock *** spacing is more important than bolt length in the case of establishing an artificial pressure *** addition to the factor of safety,the maximum allowable displacement in the tunnel and the ultimate displacement capacity of rockbolts must be also taken into account in the ***,rockbolts should be compatible with other support elements in the same support system in terms of displacement and energy absorption capacities.

关键词： Rockbolting design Pressure arch Bolt length Bolt spacing Factor of safety

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乳液pH值对乳胶粉及其涂料分散涂膜的影响

建筑材料学报 2011年第4期14卷 486-491页

作者：司徒粤周利庄蓝仁华夏正斌陈焕钦华南理工大学化学与化工学院广东广州510640

采用喷雾干燥法制备可再分散苯丙乳胶粉,探讨喷雾乳液pH值对苯丙乳胶粉及其再分散乳液性能的影响,并分析其作用机理;以不同pH值喷雾乳液制备的乳胶粉为成膜物质配制干粉涂料,研究各涂料样品的施工稳定性,并观察漆膜断面微观形貌.结果表... 详细信息

采用喷雾干燥法制备可再分散苯丙乳胶粉,探讨喷雾乳液pH值对苯丙乳胶粉及其再分散乳液性能的影响,并分析其作用机理;以不同pH值喷雾乳液制备的乳胶粉为成膜物质配制干粉涂料,研究各涂料样品的施工稳定性,并观察漆膜断面微观形貌.结果表明:随着喷雾乳液pH值增大,乳胶粉的再分散性提高、堆积密度增大,再分散乳液粒径变小,施工稳定性增强,漆膜中成膜物质对颜填料包裹更充分,但乳胶粉分散再成膜的吸水率有所升高;再分散乳液ζ电位随喷雾乳液pH值增大而先升高后降低,证实乳胶粉的再分散稳定机理为形成亲水"发状结构".综合各项性能,喷雾乳液最佳pH值为8.5.

关键词：可再分散苯丙乳胶粉干粉涂料喷雾乳液pH值

Viability of recalcitrant Araucaria angustifolia seeds in storage and in a soil seed bank

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Journal of Forestry Research 2020年第6期31卷 2413-2422页

作者： Ezequiel Gasparin Jose M.R.Faria Anderson cJose Olivia AOTonetti Rodrigo Ade Melo Henk w.M.Hilhorst Departamento de ciencias Florestais Universidade Federal de Santa Maria(UFSM)Avenida Roraima1000CamobiSanta MariaRS 97105-900Brazil Departamento de ciencias Florestais Universidade Federal de Lavras(UFLA)Caixa Postal 3017LavrasMGBrazi1 wageningen Seed Lab Laboratory of Plant PhysiologyWageningen UniversityDroevendaalsesteeg 16708 PB WageningenThe Netherlands

Araucaria angustifolia(Bertol.)Kuntze is a representative species of the Mixed Ombrophilous Forest in the Atlantic Forest Biome of *** development of a germplasm conservation protocol for long-term seed bank storage is compromised for this species,as it is sensitive to ***,in situ establishment of a soil seed bank in its natural habitat may be *** study evaluates the storability of two provenances of *** seeds and their behavior in an artificial soil seed bank in two forest environments(understory and edge).Results show that both seed provenances may be stored at 5c for approximately 12 months,retaining high *** subsequent decrease in germination was associated with a reduction and an increase in seed water content,as well as with increased electrical *** the understory environment,seed viability was above 85%for the first 60 days,and at the end of the experiment(270 days),seedlings ***,at the forest edge,there was a total loss of seed viability after 120 days associated with a reduction in water content and high *** is concluded,therefore,that short-term storage of *** seeds is possible in a cold room,which is fundamental to supply seed demand outside the production *** cover conservation is important for regeneration and conservation of the species.

关键词： Brazilian pine Desiccation sensitivity Forest cover Soil seed bank Storability