中国上映的美国电影票房影响因素分析

本文利用2012年1月至2013年12月在中国上映的84部美国电影数据,对引进的美国电影的电影票房影响因素进行实证分析。考虑到票房分布的偏态性,本文除了运用传统的OlS回归、CHOW检验,还特地采用了非参数检验方法。结果表明票房与电影预算、消费者对电影期待值、电影质量呈正相关,而与中国首映时间与外国首映放映时间差呈负相关。最后本文随机抽取了10部2014年中国上映的美国电影票房用拟合模型进行预测

Fabrication and characteristic analysis of two-dimensional anti-reflective subwavelength periodic gratings

运用等效介质理论研究了占空比随深度变化的二维亚波长光栅的抗反射原理。对全息干涉法制得的正弦型光栅进行了详细分析,表明这类光栅形成了渐变折射率的抗反膜结构。设计并利用两束相干光对称入射到记录介质(光刻胶)分两次曝光的全息方法制备了适用于可见波段的周期为310nM的二维正交正弦型光栅。测试结果表明这种光栅在整个可见光波段具有增透作用,有潜力作为传统抗反膜的替代品。将具有浮雕结构的记录介质为母版并采用模压或浇铸等方法,可将结构复制到其它材料上。这类抗反射材料具有制作简单、成本低、可大批量生产等优点。On the base of the effective medium theory(EMT),the anti-reflection property of subwavelength cross gratings with filling factors changing with depth is studied.Sinusoidal shaped gratings fabricated with holographic lithography are analyzed in detail,indicating that this kind of grating can form the structure similar to graded index anti-reflective coatings.Two-dimensional sinusoidal cross gratings with 310 nm period were designed and fabricated using double-exposure method,with two coherent beams symmetrically incident to the recording medium(photoresist).The result shows that the grating has enhanced the transmission at visible wave band,thus has the potential to replace the traditional anti-reflective coatings.Taking the recording medium with relief structures as the master and using embossing or casting methods,the structures can be replicated to other materials.Such anti-reflection materials have the merits of simple fabrication,low cost and mass production

High-Quality Quartz Thin Film Prepared by Lapping and Chemical & Mechanical Polishing Technology

石英薄膜的质量是决定各种石英基底的微纳器件品质高低的关键所在。阐述如何运用研磨和化学机械抛光CMP(CHEMICAl&MECHAnICAl POlISHIng)技术获得高品质石英薄膜的方法。由于石英属于高硬度材料,选用金刚石研磨液和球墨铸铁研磨盘对石英衬底进行研磨,以获得较高的研磨速率和较好的研磨后的表面粗糙度。在石英CMP中,采用特殊的“两步抛“工艺,对衬底进行抛光。第一步粗抛抛光液采用金刚石颗粒直径为0.3μM的研磨液与SIO2颗粒直径为50 nM的抛光液相混合,第二步精抛只采用SIO2的抛光液。实验结果表明,采用上述技术,可以获得高品质的石英薄膜,厚度为(25.1±3.2)μM,表面粗糙度约为0.89 nM(rMS)。The quality of quartz thin film is a key to various kinds of quartz-based micro and nano devices.This paper presents techniques to gain high quality quartz thin film with lapping and chemical & mechanical polishing(CMP).Due to high hardness of quartz,diamond slurry and ductile iron plate are used for lapping the quartz substrate to get higher grinding rate and better roughness of the grinded surface.Fro CMP,a special procedure of "2step-polishing"is developed,for which the first step is to use diamond slurry containing 0.3 μm particles mixed with SiO 2 slurry containing 50 nm particles,and the second step is to use only SiO 2 slurry.Tested results show that a high quality quartz film,with thickness of(25.1±3.2) μm and roughness of 0.89 nm(RMS),is acquired by using the techniques presented in the paper.国家自然科学基金重点项目(60936003

Design and Fabrication of Stack Micro-Direct Methanol Fuel CellUsing Silicon and PDMS

在堆栈式微型直接甲醇燃料电池μ-dMfC(MICrO-dIrECT METHAnOl fuEl CEll)中,为了避免硅基流场板因为封装压力过大而破裂,采用了硅和PdMS(POlydIMETHylSIlOXAnE,聚二甲基硅氧烷)材料分别制作阳极和阴极流场板。首先,采用微机电系统MEMS(MICrO-ElECTrO-MECHAnICAl SySTEMS)技术制作硅基阳极流场板。其次,通过铜箔与阴极流场板一体成型、有机清洗和PdMS表面活化等改进措施显著提升了PdMS阴极流场板金属化的能力。最后,比较和分析阳极流场板上3种不同结构的流道形式的堆栈式μ-dMfC的输出性能。实验结果表明,活化后的PdMS阴极流场板与Cr/Au的粘附性能和粘接强度显著提高,同时阳极流场板的流道一半开设为凸台,一半开设为通孔时,其堆栈式μ-dMfC的输出性能最优。最大输出电流密度为81.25 MA/CM2,最大输出功率为7.73 MW/CM2。采用硅和PdMS材料分别制作流场板,不仅简化了堆栈式μ-dMfC的结构,而且能够缓冲锁紧力,有效保护硅基阳极流场板。同时优化阳极流场板上的流道结构,能够有效提升堆栈式μ-dMfC的输出性能。In order to avoid cracks of the silicon flow field plate caused by high package pressure,silicon and PDMS(Polydimethylsiloxane)are used as anodic and cathode flow field plate respectively in the stack μ-DMFC(Micro-direct methanol fuel cell).The anodic flow field plate based on silicon is fabricated with MEMS(Micro-Electro-Mechanical Systems)technology,and cathode flow field plate is fabricated using PDMS and its metallic performance is evidently improved by means of integral shaping of copper foil and cathode flow field plate,organic cleaning and activation on PDMS surface.The output of stack μ-DMFC is tested and analyzed,in which 3 different flow channel structures on the anodic plate are introduced.Tested results verify that adhesive capability and strengthen between post-activated PDMS and Cr/Au are greatly improved,and when micro blocks and through holes are introduced alternately in the flow channel of anodic flow field plate the stack μ-DMFC can obtain the maximum output,with voltage of 0.5 V,current density of 81.25 mA/cm2 and output power density of 7.73 mW/cm2.This study shows that using silicon and PDMS as flow field plate respectively not only simplifies the structure of stack μ-DMFC but also cushions clamping force and effectively protects anodic flow field plate,and furthermore to increase the output of stack μ-DMFC by optimizing structure of flow channels on the anodic flow field plate.国家自然科学基金重点项目(60936003

中药沐足结合护理干预治疗护理人员下肢静脉曲张的效果观察

目的探讨中药沐足结合护理干预在下肢静脉曲张护士中的应用效果。方法选取某三甲综合性医院患有下肢静脉曲张的临床护士60例为研究对象,应用随机数字表法分为两组,各30例。两组研究对象均行基础护理,对照组采用医用的循序减压弹力袜进行治疗,观察组实施中药沐足结合护理干预措施。2个月后比较两组患者疗效。结果观察组研究对象静脉曲张恢复总有效率高于对照组,观察组研究对象经过3个疗程的治疗,痊愈12例,显效l3例,有效4例;对照组分别为痊愈5例,显效8例,有效9例;观察组、对照组临床治愈率和总有效率分别为40.00%、96.67%和16.67%、73.33%。差异有统计学意义(P<0.05)。结论中药沐足结合护理干预可以改善下肢静脉曲张的临床症状。福建中医药大学2016年临床专项校管课题(XB2016085

大脑淋巴瘤病的临床及MRI特点分析

目的大脑淋巴瘤病（LC）是中枢神经系统淋巴瘤（PCNSL）的特殊类型，目前报道较少，预后较其它类型的PCNSL差，早期诊断对判断预后十分重要。本文报道经脑立体定向活检明确病理的大脑淋巴瘤病3例，以提高临床医师对大脑淋巴瘤病的认识。方法回顾性分析2017年1月-2020年7月间，中山大学附属第三医院岭南医院确诊为大脑淋巴瘤病3例患者的临床表现、影像学、神经病理特征。结果3例患者分别为44、61和64岁男性，出现进展性认知下降、视物模糊、下肢乏力等神经功能障碍表现，脑部核磁共振（MRI）发现双侧大脑弥漫性脑白质病变，表现为长T1长T2信号影，T2液体衰减反转恢复序列（T2-FLAIR）呈高信号，弥散加权序列（DWI）不均匀稍高，增强扫描强化不明显，经立体定向穿刺脑组织活检取材，镜下可见弥漫性B细胞浸润，CD20（+），结合影像学特征，均确诊为B细胞来源的大脑淋巴瘤病。结论大脑淋巴瘤病为中枢神经系统淋巴瘤的特殊类型，影像诊断困难，极易误诊，对于双侧大脑半球弥漫性病变、同时累及深部脑白质和灰质结构、无强化或小斑片状强化为影像学表现的患者，注意与此病相鉴别，尽早病灶活检，明确病理诊断，对患者的早期诊断及预后具有重要意义

Efficient Preparation of β-O-4 Dilignols and Their Oxidative Coupling Studies

Efficient Preparation of β-O-4 Dilignols and Their Oxidative Coupling Studie

抽水蓄能电站地下厂房的施工项目管理

从抽水蓄能电站自身角度来说,和常规水利枢纽建设比较存在明显差异,所以其管理和常规水电站建设也会存在较大偏差。基于此,本文通过对抽水蓄能电站地下厂房的施工项目管理需求的阐述,提出了抽水蓄能电站地下厂房的施工项目管理措施。</jats:p