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Episcleral macular buckling for posterior retinal detachment in silicone oil filled eyes associated with myopic macular hole 被引量:2
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作者 Jiao Tian Luo-Sheng Tang +1 位作者 Xiao-Jian Guo Yong-Heng Luo 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2013年第2期165-168,共4页
AIM: To evaluate anatomical and visual outcomes of episcleral macular buckling (EMB) for posterior retinal detachment in silicone oil filled eyes associated with myopic macular hole.METHODS: Five cases of EMB for init... AIM: To evaluate anatomical and visual outcomes of episcleral macular buckling (EMB) for posterior retinal detachment in silicone oil filled eyes associated with myopic macular hole.METHODS: Five cases of EMB for initial failure of retinal reattachment after internal limiting membrane (ILM) peeling and silicone oil tamponade caused by myopic macular hole were retrospectively reviewed. A silicone sponge sutured directly across the macular region was performed on the silicone oil filled eyes. Silicone oil was removed no sooner than 1 month post- EMB. The duration of follow -up time after removal of silicone oil was more than 3 months.RESULTS: Retinas of five eyes were all reattached at the last follow-up. The postoperative vision ranged from counting fingers to 0.08.CONCLUSION: Anatomical results improved after EBM for posterior retinal detachment in silicone oil filled eyes associated with myopic macular hole, which was not evident for visual outcome. 展开更多
关键词 episcleral macular buckling MYOPIA macular hole retinal detachment silicone oil tamponade
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Picosecond Laser Machining of Deep Holes in Silicon Infiltrated Silicon Carbide Ceramics 被引量:1
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作者 张青 WANG Chunhui +2 位作者 LIU Yongsheng ZHANG Litong CHENG Guanghua 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2015年第3期437-441,共5页
Silicon infiltrated silicon carbide (Si-SiC) ceramics, as high hardness materials, are difficult to machine, especially drilling micro-holes. In this study, the interaction of picosecond laser pulses (1 ps at 1 030... Silicon infiltrated silicon carbide (Si-SiC) ceramics, as high hardness materials, are difficult to machine, especially drilling micro-holes. In this study, the interaction of picosecond laser pulses (1 ps at 1 030 nm) with Si-SiC ceramics was investigated. Variations of the diameter and depth of circular holes with the growth of the laser energy density were obtained. The results indicate that the increase of machining depth follows a nonlinear relation with the increasing of laser energy density, while the diameter has little change with that. Moreover, it is found that some debris and particles are deposited around and inside the holes and waviness is in the entrance and at walls of the holes after laser processing. 展开更多
关键词 picosecond laser deep holes silicon infiltrated silicon carbide ceramic
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Comparison of outcomes of idiopathic macular holes treated by vitrectomy with air or silicone oil tamponade based on the hole size 被引量:2
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作者 Lan Yin An-Qi Liu +2 位作者 Xin Jin Liang Jia Feng-Xiang Wang 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2022年第8期1305-1309,共5页
AIM:To compare the efficacy of vitrectomy combined with air or silicone oil in the treatment of idiopathic macular hole(IMH).METHODS:According to the results of high-definition optical coherence tomography(HD-OCT),75 ... AIM:To compare the efficacy of vitrectomy combined with air or silicone oil in the treatment of idiopathic macular hole(IMH).METHODS:According to the results of high-definition optical coherence tomography(HD-OCT),75 cases(75 eyes)of IMH in stage II-IV(Gass stage)in the General Hospital of Chinese PLA from January 2017 to December 2019 were collected for this retrospective study.The best corrected visual acuity(BCVA)and minimum diameter of IMH(MMHD)were measured.Eyes underwent vitrectomy combined with internal limiting membrane peeling operation,and were divided into disinfection air group(30 eyes)and silicone oil group(45 eyes)according to the intraocular tamponade.For MMHD≤400μm(MMHD1),there were 23 eyes in air group and 16 eyes in silicone oil group.For MMHD2>400μm(MMHD2),there were 7 eyes in air group and 29 eyes in silicone oil group.One month after surgery,the closure rates of IMH and BCVA were compared and analyzed.According to HD-OCT,the closure shape was graded with A(bridge closure)and B(good closure).RESULTS:The closure rates of air group and silicone oil group were 86.67%and 95.56%respectively with no significant difference(P>0.05);For MMHD1,those of air group and silicone oil group were 95.65%and 100%respectively with no significant difference(P>0.05);For MMHD2,those of air group and silicone oil group were 57.14%and 93.10%respectively,and those of the silicone oil group were higher than the air group(P<0.05).There was no significant difference in the closure shape grade between MMHD1 air group and silicone oil group(P>0.05).The proportion of Grade B in MMHD2 silicone oil group was higher than that in the air group(P<0.05).BCVA of each group after operation was better than that before operation,and there was no significant difference between air group and silicone oil group.While among them,MMHD1 air group was better than silicone oil group(P<0.05),and there was no significant difference between MMHD2 air group and silicone oil group(P>0.05).CONCLUSION:For smaller IMH(≤400μm),the efficacy of vitrectomy combined with air should be considered better than silicone oil;for larger IMH(>400μm),the efficacy of silicone oil may be better than air. 展开更多
关键词 idiopathic macular hole vitreoretinal surgery silicone oil AIR
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Sub-stochiometric MoO_(x) by radio-frequency magnetron sputtering as hole-selective passivating contacts for silicon heterojunction solar cells
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作者 Xiufang Yang Shengsheng Zhao +6 位作者 Qian Huang Cao Yu Jiakai Zhou Xiaoning Liu Xianglin Su Ying Zhao Guofu Hou 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第9期597-603,共7页
The silicon heterojunction(SHJ)solar cell has long been considered as one of the most promising candidates for the next-generation PV market.Transition metal oxides(TMOs)show good carrier selectivity when combined wit... The silicon heterojunction(SHJ)solar cell has long been considered as one of the most promising candidates for the next-generation PV market.Transition metal oxides(TMOs)show good carrier selectivity when combined with c-Si solar cells.This has led to the rapid demonstration of the remarkable potential of TMOs(especially MoO_(x))with high work function to replace the p-type a-Si:H emitting layer.MoO_(x) can induce a strong inversion layer on the interface of n-type c-Si,which is beneficial to the extraction and conduction of holes.In this paper,the radio-frequency(RF)magnetron sputtering is used to deposit MoO_(x) films.The optical,electrical and structural properties of MoO_(x) films are measured and analyzed,with focus on the inherent compositions and work function.Then the MoO_(x) films are applied into SHJ solar cells.When the MoO_(x) works as a buffer layer between ITO/p-a-Si:H interface in the reference SHJ solar cell,a conversion efficiency of 19.1%can be obtained.When the MoOx is used as a hole transport layer(HTL),the device indicates a desirable conversion efficiency of 17.5%.To the best of our knowledge,this current efficiency is the highest one for the MoO_(x) film as HTL by RF sputtering. 展开更多
关键词 radio-frequency magnetron sputtering silicon heterojunction(SHJ)solar cell MoO_(x) hole transport layer
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Localized electronic states in gaps on hole-net structures of silicon
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作者 黄伟其 吕泉 +2 位作者 张荣涛 王晓允 于示强 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第11期5066-5071,共6页
Hole-net structure silicon is fabricated by laser irradiation and annealing, on which a photoluminescence (PL) band in a the region of 650-750 nm is pinned and its intensity increases obviously after oxidation. It i... Hole-net structure silicon is fabricated by laser irradiation and annealing, on which a photoluminescence (PL) band in a the region of 650-750 nm is pinned and its intensity increases obviously after oxidation. It is found that the PL intensity changes with both laser irradiation time and annealing time. Calculations show that some localized states appear in the band gap of the smaller nanocrystal when Silo bonds or Si-O-Si bonds are passivated on the surface. It is discovered that the density and the number of Si=O bonds or Si-O-Si bonds related to both the irradiation time and the annealing time obviously affect the generation of the localized gap states of hole-net silicon, by which the production of stimulated emission through controlling oxidation time can be explained. 展开更多
关键词 hole-net silicon passivated bonds localized gap states
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高度近视黄斑裂孔性视网膜脱离行玻璃体切割术后C_(3)F_(8)与硅油填充的疗效比较
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作者 温晓英 杨娜 +3 位作者 张月玲 马伟娜 付燕 耿任飞 《国际眼科杂志》 CAS 2024年第5期805-809,共5页
目的:比较高度近视黄斑裂孔性视网膜脱离(MHRD)行玻璃体切割联合内界膜剥离后玻璃体腔内分别行硅油或C_(3)F_(8)填充治疗的疗效观察。方法:回顾性临床研究。2019-01/2022-08就诊于我院的45例45眼高度近视MHRD患者,根据手术方式分为硅油... 目的:比较高度近视黄斑裂孔性视网膜脱离(MHRD)行玻璃体切割联合内界膜剥离后玻璃体腔内分别行硅油或C_(3)F_(8)填充治疗的疗效观察。方法:回顾性临床研究。2019-01/2022-08就诊于我院的45例45眼高度近视MHRD患者,根据手术方式分为硅油组(23例)及C_(3)F_(8)组(22例),两组患者均常规三切口玻璃体切割手术,内界膜剥离后行内界膜填塞、自体血覆盖,硅油填充组行硅油填充,C_(3)F_(8)组行15%C_(3)F_(8)气体填充。两组患者分别观察最佳矫正视力(BCVA)、多焦视网膜电图(mfERG)、裂孔的闭合及视网膜复位情况,统计两组患者术后并发症情况。结果:C_(3)F_(8)组、硅油组患者裂孔闭合率为77%、83%(P>0.05),视网膜复位率分别为95%、96%(P>0.05)。C_(3)F_(8)组、硅油组术后视力分别为0.99±0.34、1.22±0.37,C_(3)F_(8)组视力优于硅油组(t=-2.156,P=0.037),两组均较术前显著提高。术后12 mo,两组患者mfERG一阶函数1环(C_(3)F_(8)组114.27±26.37 nV/deg2,硅油组98.08±24.36 nV/deg2)及2环(C_(3)F_(8)组80.45±14.94 nV/deg2,硅油组67.73±15.33 nV/deg2)P1波反应密度较术前(1环P1波反应密度:C_(3)F_(8)组58.13±13.96 nV/deg2、硅油组55.30±10.48 nV/deg2;2环P1波反应密度:C_(3)F_(8)组51.18±8.19 nV/deg2、硅油组47.43±11.97 nV/deg2)明显增加(均P<0.05),C_(3)F_(8)组较硅油组增加明显(P<0.05)。硅油组与C_(3)F_(8)组患者术后并发症发生情况无差异(P>0.05)。结论:玻璃体切割联合内界膜剥离后玻璃体腔内分别行硅油或C_(3)F_(8)填充均可促进高度近视MHRD患者视网膜复位及黄斑裂孔闭合,而且在视功能恢复C_(3)F_(8)填充优于硅油填充。 展开更多
关键词 黄斑裂孔性视网膜脱离 高度近视 玻璃体切割术 硅油填充 C_(3)F_(8)填充
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基于金刚线切片的钙钛矿/硅叠层太阳电池
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作者 苏诗茜 应智琴 +3 位作者 陈邢凯 李鑫 杨熹 叶继春 《太阳能学报》 EI CAS CSCD 北大核心 2024年第4期23-29,共7页
提出一种免空穴传输层的策略,将自组装单分子层材料作为钙钛矿活性层的添加剂,通过一步旋涂法直接将钙钛矿薄膜制备在导电基底表面,其中薄膜的质量与均一性都得到改善。进一步地,将该方法应用在低成本的商用金刚线切片上,可在高粗糙度... 提出一种免空穴传输层的策略,将自组装单分子层材料作为钙钛矿活性层的添加剂,通过一步旋涂法直接将钙钛矿薄膜制备在导电基底表面,其中薄膜的质量与均一性都得到改善。进一步地,将该方法应用在低成本的商用金刚线切片上,可在高粗糙度的硅表面制备出覆盖度高、形貌致密、无空洞的钙钛矿薄膜。在光电性能方面,用该方法得到的单结钙钛矿太阳电池的光电转换效率为21%,填充因子高达83%,两端钙钛矿/硅叠层太阳电池的光电转换效率为28%。 展开更多
关键词 钙钛矿太阳电池 自组装单分子层材料 添加剂 免空穴传输层 金刚线切片 钙钛矿/硅叠层太阳电池
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Rapid manufacturing of SiC molds with micro-sized holes using abrasive water jet 被引量:1
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作者 Bo-Sung SHIN Kang-Su PARK +5 位作者 Yeon-Kyoung BAHK Sun-Ki PARK Jung-Han LEE Jeung-Sang GO Myung-Chang KANG Chae-Moon LEE 《中国有色金属学会会刊:英文版》 CSCD 2009年第B09期178-182,共5页
Silicon carbide (SiC) is highly wear resistant with good mechanical properties, including high temperature strength, excellent chemical resistance, and high thermal conductivity and thermal shock resistance. SiC molds... Silicon carbide (SiC) is highly wear resistant with good mechanical properties, including high temperature strength, excellent chemical resistance, and high thermal conductivity and thermal shock resistance. SiC molds, which can be produced with diverse microstructural features, are now widely used in glass molding owing to their excellent characteristics, and also have potential applicability in IT industries. SiC molds are traditionally fabricated by silicon micromachining or dicing. The fabrication cost of silicon micromachining is very high, however, because several expensive masks are needed. Furthermore, the fabrication time is very long. Meanwhile, it is difficult to make micro-patterned molds with arbitrary shapes using dicing saws. Abrasive water jet (AWJ) is widely applied to cut and drill very brittle, soft and fibrous materials. It offers high energy density, the absence of a heat affected zone(HAZ), high performance, and an environment friendly process. In spite of these advantages, micro-hole drilling via conventional AWJ processing suffers from notable shortcomings. We proposed a new abrasive supplying method of AWJ. The proposed method reduces frosting phenomena, and provides micro-machining of AWJ. The characteristics of a hole machined was investigated by the proposed AWJ process according to the ratio of water and abrasives. With the optimal experimental conditions, 3×3 array SiC molds with the diameter of 700 μm and depth of 900 μm were successfully manufactured. 展开更多
关键词 快速模具制造 磨料水射流 碳化硅 微型 硅微加工 型孔 最佳实验条件 机械性能
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Different charging behaviors between electrons and holes in Si nanocrystals embedded in SiN_x matrix by the influence of near-interface oxide traps
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作者 方忠慧 江小帆 +3 位作者 陈坤基 王越飞 李伟 徐骏 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第1期457-461,共5页
Si-rich silicon nitride films are prepared by plasma-enhanced chemical vapor deposition method, followed by thermal annealing to form the Si nanocrystals(Si-NCs) embedded in Si Nx floating gate MOS structures. The c... Si-rich silicon nitride films are prepared by plasma-enhanced chemical vapor deposition method, followed by thermal annealing to form the Si nanocrystals(Si-NCs) embedded in Si Nx floating gate MOS structures. The capacitance–voltage(C–V), current–voltage(I–V), and admittance–voltage(G–V) measurements are used to investigate the charging characteristics. It is found that the maximum flat band voltage shift(△VFB) due to full charged holes(~ 6.2 V) is much larger than that due to full charged electrons(~ 1 V). The charging displacement current peaks of electrons and holes can be also observed by the I–V measurements, respectively. From the G–V measurements we find that the hole injection is influenced by the oxide hole traps which are located near the Si O2/Si-substrate interface. Combining the results of C–V and G–V measurements, we find that the hole charging of the Si-NCs occurs via a two-step tunneling mechanism. The evolution of G–V peak originated from oxide traps exhibits the process of hole injection into these defects and transferring to the Si-NCs. 展开更多
关键词 silicon nanocrystals memory different charging of electrons and holes oxide traps admittancevoltage characteristics
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Easy-to-fabricate high efficiency silicon nanowires solar cell modified by CdTe and zinc tetraphenyl porphyrin nanostructures
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作者 Debanjan Maity Saurabh Kumar Pathak Melepurath Deepa 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第12期484-497,I0012,共15页
Liquid junction solar cell(LJSC) with vertically silicon nanowires(SiNWs) as the primary photosensitizer,co-sensitized with luminescent and narrow gap CdTe nanoparticles,and cuboidal microstructures of zinc tetrapheny... Liquid junction solar cell(LJSC) with vertically silicon nanowires(SiNWs) as the primary photosensitizer,co-sensitized with luminescent and narrow gap CdTe nanoparticles,and cuboidal microstructures of zinc tetraphenyl porphyrin(ZnTPP) dye offers broad and intense visible light absorption that translates into a maximum power conversion efficiency(PCE) of 9.09%,when combined with a polymeric gel of a I_(2)/I^(-)redox couple as the hole transport material and a counter electrode(CE) of poly(3,4-ethyelenedioxythio phene) doped with imide ions(PEDOT-N(CF_(3) SO_(2))_(2)),under 1 sun irradiance.The p-type CdTe efficiently scavenges holes from SiNWs and simultaneously allows the passage of photoexcited electrons from ZnTPP to SiNWs via electrical conduction thus imparting an enhanced solar cell performance.Cosensitization also supresses back electron transfer effectively,as is inferred from a ~68% enhancement in PCE compared to SiNWs alone.Optimization of the CE entailed the evaluation of the effect of dopant anion:imide versus dicyanamide in PEDOT,and revealed that the presence of macro-cracks in the polymer surface,a deeper work function,and a lower electrical conductance are the shortcomings of the dicyanamide doped PEDOT and reduce the overall PCE,compared to imide.This study brings out how by judicious choice of photoanode and CE components,efficient,stable and easy-to-assemble LJSCs can be developed. 展开更多
关键词 silicon NANOWIRES PORPHYRIN Solar cell hole transfer
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高体分铝基碳化硅超声振动钻削的内孔表面质量试验研究 被引量:2
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作者 马利杰 屈海涛 +3 位作者 马尊严 逄明华 冯启高 王占奎 《工具技术》 北大核心 2023年第2期33-38,共6页
针对高体分铝基碳化硅精密钻削加工技术难题,利用普通超声振动钻削(UVD)和超声振动啄式钻削(UVPD)两种工艺,通过均匀试验设计,对高体分铝基碳化硅套料钻削的内孔表面质量的变化规律及产生原因进行了深入的直观分析和回归分析。结果表明... 针对高体分铝基碳化硅精密钻削加工技术难题,利用普通超声振动钻削(UVD)和超声振动啄式钻削(UVPD)两种工艺,通过均匀试验设计,对高体分铝基碳化硅套料钻削的内孔表面质量的变化规律及产生原因进行了深入的直观分析和回归分析。结果表明:高体分铝基碳化硅套料钻削时,内孔表面缺陷表现为SiC颗粒拔出、SiC颗粒破裂、Al基体塑性变形三种形式;采用UVD能够获得比普通钻削更好的内孔质量,而采用UVPD的表面粗糙度可比UVD降低20%以上,各工艺条件下表面缺陷特征的差异是导致内孔质量变化的根本原因;无论UVD还是UVPD,超声振幅和进给速度都是影响内孔质量的重要因素,增大超声振幅或降低进给速度都有利于提高内孔质量。 展开更多
关键词 高体分铝基碳化硅 超声振动钻削 内孔表面质量 均匀试验设计
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玻璃体切除联合硅油填充治疗复发性黄斑裂孔视网膜脱离的疗效分析
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作者 王剑 《智慧健康》 2023年第6期201-204,共4页
目的 分析玻璃体切除联合硅油填充治疗复发性黄斑裂孔视网膜脱离(macular hole retinal detachment, MHRD)的疗效。方法 采取计算机随机分组法,将本院于2020年1月-2022年1月收治的100例复发性MHRD患者分为50例/组,均接受玻璃体切除术治... 目的 分析玻璃体切除联合硅油填充治疗复发性黄斑裂孔视网膜脱离(macular hole retinal detachment, MHRD)的疗效。方法 采取计算机随机分组法,将本院于2020年1月-2022年1月收治的100例复发性MHRD患者分为50例/组,均接受玻璃体切除术治疗,对照组联合14%C3F8气体填充,观察组联合硅油填充治疗。对比术后视网膜复位率、黄斑裂孔闭合率、logMAR-BCAV值、并发症发生率。结果 两组术后视网膜复位率、并发症发生率差异不大(P>0.05),观察组黄斑裂孔闭合率高于对照组,术后logMARBCAV值低于对照组(P<0.05)。结论 在复发性MHRD的临床治疗中,采取玻璃体切除联合硅油填充治疗方案效果理想。 展开更多
关键词 复发性 黄斑裂孔视网膜脱离 玻璃体切除术 硅油填充
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井底参数新型检测手段设计研究 被引量:2
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作者 汤凤林 赵荣欣 +2 位作者 周欣 段隆臣 ЧихоткинВ.Ф. 《钻探工程》 2023年第2期1-7,共7页
绝缘硅(SOI)是一种新型电子材料。俄罗斯利用SOI技术设计研究出了一种新型井底参数检测手段,包括顶角测量仪和井底钻井液压力测量仪。这种手段具有热稳定性好、抗辐射能力强、精度高、灵敏度好和可靠性高的特点。建议引起重视并对此进... 绝缘硅(SOI)是一种新型电子材料。俄罗斯利用SOI技术设计研究出了一种新型井底参数检测手段,包括顶角测量仪和井底钻井液压力测量仪。这种手段具有热稳定性好、抗辐射能力强、精度高、灵敏度好和可靠性高的特点。建议引起重视并对此进行讨论和研究。 展开更多
关键词 绝缘硅 井底参数检测手段 热稳定性 抗辐射能力 深部钻进
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航空零件表面处理过程中孔保护的方法
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作者 杨含 乔永莲 +2 位作者 刘晓君 徐健 马雯雯 《电镀与涂饰》 CAS 北大核心 2023年第1期60-65,共6页
针对传统航空零件表面处理过程中孔保护材料和方法的保护效果不佳的问题,通过使用由耐高温、耐强酸及耐强碱材料制成的T型硅橡胶塞、柱型硅橡胶塞、机械膨胀塞,以及刷涂可剥离保护胶,在表面处理过程中对各类孔进行保护,通过目视检查和... 针对传统航空零件表面处理过程中孔保护材料和方法的保护效果不佳的问题,通过使用由耐高温、耐强酸及耐强碱材料制成的T型硅橡胶塞、柱型硅橡胶塞、机械膨胀塞,以及刷涂可剥离保护胶,在表面处理过程中对各类孔进行保护,通过目视检查和装配验证评价了各自的保护效果。结果表明,上述4种方法对各类孔都有很好的保护效果。 展开更多
关键词 航空零件 表面处理 保护 硅橡胶塞 机械膨胀塞 可剥离保护胶
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硅片纳秒激光附加电流打孔实验研究
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作者 李锦超 张伟 +2 位作者 郑宏宇 高军 蒋超 《现代制造工程》 CSCD 北大核心 2023年第9期111-116,136,共7页
针对硅片具有反射率高、吸收率低等缺点,为了提高纳秒激光(波长为355 nm)在硅片上打孔蚀除材料效率,设计附加电流场装置,建立单脉冲烧蚀阈值模型,经过实验计算得到硅片烧蚀阈值为1.885 J/cm^(2)。采用电流场辅助激光环切式进行硅片打孔... 针对硅片具有反射率高、吸收率低等缺点,为了提高纳秒激光(波长为355 nm)在硅片上打孔蚀除材料效率,设计附加电流场装置,建立单脉冲烧蚀阈值模型,经过实验计算得到硅片烧蚀阈值为1.885 J/cm^(2)。采用电流场辅助激光环切式进行硅片打孔,分别在激光加工次数和附加电流不同时做实验研究,当激光加工次数较少而附加电流较大时,激光加工的微孔入口孔和出口孔直径均显著增加,锥度减小,蚀除材料效率增大;当激光加工次数较多时,施加电流后由于多脉冲的累积效应,微孔直径变化不明显,这是由于附加电流场导致硅片内自由电子增多,更多的自由电子与激光光子发生碰撞,增加硅片对激光能量的吸收。实验表明,附加电流增加了硅片对波长为355 nm纳秒激光光子的吸收率,提高了硅片蚀除材料效率,也为高效率的纳秒激光加工硅片提供一种新方法。 展开更多
关键词 硅片激光加工 附加电流 烧蚀阈值 微孔形貌 多脉冲累积效应
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玻璃体切割联合硅油填充与C3F8填充治疗高度近视黄斑裂孔视网膜脱离临床效果比较 被引量:11
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作者 于文贞 孙摇遥 +6 位作者 李娟 赵敏 黎晓新 姜燕荣 赵明威 梁建宏 尹虹 《中华实验眼科杂志》 CAS CSCD 北大核心 2012年第11期1036-1039,共4页
背景高度近视黄斑裂孔视网膜脱离(MHRD)可造成严重的视力下降,经睫状体平坦部的玻璃体切割术联合眼内填充术已应用于该病的临床治疗,目前常用的眼内填充物包括硅油及可膨胀性气体C3F8,两种填充物的效果比较仍缺少相关研究证据。目... 背景高度近视黄斑裂孔视网膜脱离(MHRD)可造成严重的视力下降,经睫状体平坦部的玻璃体切割术联合眼内填充术已应用于该病的临床治疗,目前常用的眼内填充物包括硅油及可膨胀性气体C3F8,两种填充物的效果比较仍缺少相关研究证据。目的评价玻璃体切割联合硅油填充与C3F8填充治疗高度近视黄斑裂孔视网膜脱离的手术效果。方法采用回顾性病例对照设计。对采用玻璃体切割联合眼内填充术治疗的51例高度近视MHRD患者,根据术中眼内填充物的不同将患者分为硅油填充组和C3F8填充组,两组患者基线资料一致。对两组术眼术后的最佳矫正视力(BCVA)、视网膜复位率、黄斑裂孔闭合情况及视网膜脱离复发率进行分析和比较。结果两组患者术前视力差异无统计学意义(U=266.000,P=0.286),基线视力一致,术中不同眼内填充物治疗后视力差异亦无统计学意义(U=205.000,P=0.029);应用硅油填充及C3F8填充患者BCVA术后与术前相比均有显著提高,差异均有统计学意义(Z=-2.729,P=0.006;Z=-3.273,P=0.001),两组患者术后视网膜脱离发生率及黄斑裂孔解剖闭合率差异均无统计学意义(P=0.894、1.000)。患者除自内障外无其他并发症发生。结论应用C3F8填充治疗高度近视MHRD与硅油填充治疗效果相同,且均安全、有效。 展开更多
关键词 高度近视 黄斑裂孔视网膜脱离 玻璃体切割 硅油 C3F8
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稀土对A356.2铝合金气孔和共晶硅形貌的影响 被引量:12
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作者 闫洪 谢刚 +2 位作者 李全 张辉 杨祖贵 《铸造技术》 CAS 北大核心 2013年第5期527-528,共2页
研究了稀土对A356.2铝合金显微组织的影响。结果表明:稀土能使铝合金中的气孔尺寸减小,共晶硅由针片状和大块状变为颗粒状。
关键词 稀土 A356 2铝合金 气孔 共晶硅
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乾安地区井壁坍塌机理及钻井液技术研究 被引量:13
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作者 孙玉学 王媛慧 +1 位作者 李玉莲 赵诚 《钻井液与完井液》 CAS 2009年第5期76-78,共3页
吉林油田乾安地区存在着严重的井壁坍塌、掉块等问题。利用X-射线衍射分析、电镜扫描、分光光度法、电动电位分析、滚动回收率测试和膨胀率测试等实验手段,对乾安地区岩样的结构及理化性能进行了系统分析。通过分析认识到,该地区泥页岩... 吉林油田乾安地区存在着严重的井壁坍塌、掉块等问题。利用X-射线衍射分析、电镜扫描、分光光度法、电动电位分析、滚动回收率测试和膨胀率测试等实验手段,对乾安地区岩样的结构及理化性能进行了系统分析。通过分析认识到,该地区泥页岩属中~弱膨胀和中~弱分散的硬脆性泥页岩,并进一步讨论了该地区复杂地层井壁坍塌的机理,形成了满足该地区地层钻井要求的有机硅成膜钻井液。现场试验结果表明,该钻井液能有效控制该地区的井壁失稳,大幅度降低井下复杂情况的发生。 展开更多
关键词 井眼稳定 有机硅成膜钻井液 作用机理 乾安地区
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硅橡胶分子量对硅泡沫性能影响的研究 被引量:5
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作者 陈美华 罗世凯 +2 位作者 赵祺 雷卫华 李艳 《化工新型材料》 CAS CSCD 北大核心 2011年第8期65-68,共4页
选用4种不同分子量的液体硅橡胶(107硅橡胶)作为生胶制备出了室温下固化的硅橡胶泡沫材料。探讨了生胶胶料黏度对固化速度的影响,以及分子量大小对硅泡沫的泡孔形貌、物理力学性能、热稳定性的影响。随着基础胶料黏度的增大,凝胶时间及... 选用4种不同分子量的液体硅橡胶(107硅橡胶)作为生胶制备出了室温下固化的硅橡胶泡沫材料。探讨了生胶胶料黏度对固化速度的影响,以及分子量大小对硅泡沫的泡孔形貌、物理力学性能、热稳定性的影响。随着基础胶料黏度的增大,凝胶时间及其表干时间缩短,即固化速度加快;随着生胶分子量的增大,硅泡沫的泡孔变小,拉伸强度、压缩模量逐渐增大,压缩永久变形逐渐减小;生胶分子量对硅泡沫的热稳定性影响较小,白炭黑的加入有利于提高硅泡沫的热稳定性。 展开更多
关键词 107硅橡胶 泡孔形貌 力学性能 热稳定性
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过共晶铝硅合金缸体/缸套工作面加工技术及应用 被引量:9
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作者 孙廷富 杨波 +3 位作者 翟景 郭安振 郭锋 崔崇亮 《兵器材料科学与工程》 CAS CSCD 北大核心 2013年第5期120-124,共5页
综述了低过共晶铝硅合金、中过共晶铝硅合金以及高过共晶铝硅合金缸体/缸套材料的研究及进展情况,详细叙述了缸体孔/缸套工作面激光合金化、激光刻蚀、珩磨加工、等离子体涂覆、化学腐蚀等加工技术,对存在的问题进行分析总结,并提出解... 综述了低过共晶铝硅合金、中过共晶铝硅合金以及高过共晶铝硅合金缸体/缸套材料的研究及进展情况,详细叙述了缸体孔/缸套工作面激光合金化、激光刻蚀、珩磨加工、等离子体涂覆、化学腐蚀等加工技术,对存在的问题进行分析总结,并提出解决方法。 展开更多
关键词 低过共晶铝硅合金缸体孔 中过共晶铝硅合金缸体孔 高过共晶铝硅合金缸套 缸套工作面 腐蚀加工
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