oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 200 )

2018 ( 2930 )

2017 ( 3063 )

2016 ( 3141 )

Custom range...

Search Results: 1 - 10 of 167837 matches for " 葛振林XU Geng-chi "
All listed articles are free for downloading (OA Articles)
Page 1 /167837
Display every page Item
非拔牙矫治上牙列重度拥挤1例
Non-extraction Treatment for Severe Dentition Crowding: A Case Report

牟兰,张晓波,徐庚池,
MU Lan
, ZHANG Xiao-bo,XU Geng-chi, GE Zhen-lin.

- , 2016, DOI: 10.11839/kqyxzh.2016.01.02
Abstract: 摘要 目的:分析重度拥挤非拔牙矫治病例。方法:用磨牙推进器联合MBT直丝弓技术排齐牙列。结果:矫治结束后患者直面型维持较好,上下牙列排齐。结论:在生长发育高峰期,磨牙推进器可有效矫治牙列重度拥挤
位点保存术在关闭拔牙间隙预防牙龈折痕的临床应用
Clinical Application of Alveolar Ridge Preservation Techniques in the Orthodontic Space Closure to Prevent Gingival Invagination

徐庚池,韩耀辉,牟兰,
XU Geng-chi
, HAN Yao-hui, MOU Lan, GE Zhen-lin

- , 2015,
Abstract: 摘要 目的:研究位点保存术对正畸拔牙间隙关闭过程中出现牙龈折痕的影响,以评价该技术在临床应用的可行性。方法:选择对称性拔除双侧第一前磨牙的正畸病例3例,6对牙齿,采用自身左右对照。随机选取一侧进行位点保存,另一侧拔牙后进行常规处理,作为对照,术后6周开始正畸治疗。选用牙周探针进行测量,对比两组牙龈折痕的发生情况。结果:对照组上颌1例患者,下颌所有患者中均出现牙龈折痕,实验组观察到牙龈折痕的出现。结论:位点保存术能够对抗拔牙窝的萎缩,有效的预防牙龈折痕的发生
正畸拔牙矫治病例中出现牙龈折痕的临床研究
Clinical Study on Gingival Invagination after Tooth Extraction and Orthodontic Treatment.

徐庚池, 张晓波, 牟兰, 韩耀辉,
XU Geng-chi
,ZHANG Xiao-bo, MOU Lan,HAN Yao-hui,GE Zhen-lin

- , 2016, DOI: 10.13701/j.cnki.kqyxyj.2016.03.017
Abstract: 摘要 目的: 探讨正畸拔牙矫治病例出现牙龈折痕原因,为临床预防牙龈折痕的发生提供依据。方法: 在拔除前磨牙进行固定矫治的错牙合畸形患者中,筛查出发生的牙龈折痕病例87例,选择其中一侧出现牙龈折痕,另一侧未出现的病例65例,将出现牙龈折痕的一侧作为实验侧,未出现牙龈折痕的一侧作为对照侧,通过CBCT测量分析,比较两侧牙槽骨宽度、高度及骨密度的变化与出现牙龈折痕的相关性。结果: 牙龈折痕多发生在下颌,牙周探针牙龈折痕深度下颌均大于上颌。牙龈折痕侧牙槽骨宽度减小、高度降低以及密度减小均明显大于对照组,两组数据统计结果有显著性差(P<0.05)。结论: 正畸拔牙矫治病例中牙龈折痕的出现与牙槽骨宽度、高度及骨密度的变化具有相关性,拔牙间隙关闭过程中牙槽骨吸收,对软组织支持的丧失,可能是出现牙龈折痕的解剖学因素
Smog Chamber Simulation of Atmospheric Photochemical Reactions of Acetylene and NOx
烟雾箱模拟乙炔和NOx的大气光化学反应

DU Lin,XU Yong-fu,GE Mao-f,JIA Long,WANG Geng-chen,WANG Dian-xun,
,徐永福,茂发,贾龙,王庚辰,王殿勋

环境科学 , 2007,
Abstract: A series of characteristic experiments were conducted in a self-made photochemical smog chamber, which was used to simulate atmospheric photochemical reactions of acetylene and NO(x) under room temperature of (20 +/- 1) degrees C. The effect of acetylene and NO(x) on ozone production by photochemical reactions was discussed. The wall decay of O3 and NO2 were determined, which were 5.80 x 10(-6) s(-1) and 2.41 x 10(-6) s(-1), respectively. Such decay should be omitted relative to O3 and NO2 in simulative experiments. The effective light intensity for a single black lamp of 40 W was determined to be 0.64 x 10(-3) s(-1), which was expressed by the photolysis rate of NO2. The effect of different light intensity, initial concentrations of acetylene and NO(x) on O3 production was discussed after correction of background O3 from purified air. The incremental reactivity (IR) of acetylene were calculated. For four different experiments, the maximum values of IR are 1.76 x 10(-2), 2.68 x 10(-2), 2.04 x 10(-2) and 2.84 x 10(-2), respectively. It is found that there are close relationships between IR and initial acetylene concentrations, and between IR and irradiation intensity, and that there is no significant relation between IR and initial NO(x) concentrations.
Responses of nutrients diffusion fluxes across the sediment-water interface in tidalflats to salinity variance: a case study of Daguhe Estuary, Jiaozhou Bay
胶州湾大沽河潮滩营养盐在沉积物-水界面的扩散通量对盐度变化的响应

Ge Chang zi,Zhang Fan,Xu Bin duo,Ren Yi ping,Liang Zhen lin,
长字
,张帆,徐宾铎,任一平,

水生态学杂志 , 2011,
Abstract: 2009年3、6、9和12月在胶州湾大沽河河口潮滩采集均长25cm的沉积物柱状样,利用室内培养法,培养柱状样72h。该时间段内的营养盐在水—沉积物界面的平均迁移速度视为营养盐的扩散通量。在培养中,上覆水的盐度,分别被调整到17、22和28。不同盐度水平下,氨氮和磷酸盐在沉积物—水界面的扩散通量具有明显的时空异质性;在所测试的盐度范围内,氨氮的扩散通量与盐度的相关性并不显著;而盐度对磷酸盐在沉积物—水界面的扩散具有显著的影响。在6月和9月,所有测试站位中均表现为盐度增加,磷酸盐的扩散速度下降。大沽河径流的衰减会抑制磷酸盐自沉积物向水体释放,从而导致初级生产磷的供应不足。因此,大沽河径流的降低是大沽河潮滩湿地生态功能退化的一个原因。
Forming Mechanism of Spatial Structure of Commercial Types in Guangzhou City
广州市商业业态空间形成机理

LIN Geng,XU Xueqiang,
,许学强

地理学报 , 2004,
Abstract: Focused on the influencing factors, such as industry, land use, behavior, traffic, history, and culture, the dissertation explores the formed mechanism of commercial types in Guangzhou and evaluates the benefits of its spatial structure under multi factors. The paper defines the study concepts. Based on the quantity, structure and distribution of land supply in Guangzhou, the paper analyzes the relationship between urban land expansion and spatial structure of commercial types. It is concluded that there is spatial accrete characteristic between commerce and real estate, and the degree of integration affects the developmental level of spatial structure of retail. The paper explores the effect of traffic network on spatial structure of commercial types. Urban external traffic arteries mostly affect the spatial structure of wholesale business, and the internal traffic lines combined with real estate generally lead to the expansion of spatial structure of retail. The authors consider that the demand and tendency of consumers cause the differentiation of function about spatial structure of retail. The paper probes into the relationship of history, culture and spatial structure of commercial types in Guangzhou. It is concluded that the core-fringe structure of traditional business streets, modern shopping centers and storage marketplaces in built-up area of Guangzhou is gradually appearing. Finally, the authors summarize the forming mechanism of spatial structure of commercial types by all factors, and evaluate its benefit.
SYNTHESIS AND CHARACTERIZATION OF POLYIMIDE WITH ARYLENE SULFIDE STRUCTURE
含硫醚结构均苯型聚酰亚胺的合成及表征

ZHANG Yi,ZHENG Xuefei,NIU Xinxing,ZHANG Yanzhu,XIAO Shanxiong,LIN Wenxuan,LIU Siwei,HUANG Aiping,CHI Zhenguo,XU Jiarui,
张艺
,郑雪菲,牛新星,张燕珠,肖善雄,文璇,刘四委,黄爱萍,,许家瑞

高分子学报 , 2010,
Abstract: 以4,4′-二氨基二苯硫醚(SDA)和均苯四酸酐(PMDA)为原料,通过溶液缩聚法热酰亚胺/化学酰亚胺化的方法制备了一种含硫醚结构均苯型聚酰亚胺.利用高级旋转流变仪建立了在线跟踪反应进程的方法,采用热失重分析仪研究反应条件对热酰亚胺化及化学酰亚胺化法的影响,这些方法的建立为进一步制备高性能的聚酰亚胺提供有效的实验手段.采用小角激光光散射法、红外光谱、元素分析、接触角仪、DSC等方法对聚合物的结构与性能进行表征.结果显示,硫醚结构的引入,可有效改善聚合物薄膜的表面性能,其与铜箔之间的粘附功明显大于传统聚酰亚胺,在无胶挠性线路板应用方面显示出较好的应用前景.所获聚合物的Mw为(6.7±1.6)×104,分解温度均高于560℃;DSC的结果显示所制备的两种酰亚胺化聚合物均具有较高的玻璃化转变温度,相比之下,化学酰亚胺化更有利于获得高酰亚胺化程度的聚合物,产物的玻璃化转变温度也更高.
多功能通用综合查询模块的开发
郑志彬,吴昊,,
计算机系统应用 , 1997,
Abstract: 本文介绍了如何在MIS开发中建立了一个实用的通用查询模块。叙述了该查询模块的程序设计思想、程序设计和程序调用方法,该模块充分考虑了数据库软件使用的实际情况,具有良好的实用性及通用性。
历史时期(1803~1958年)西藏水灾分析
张雪芹,全胜,耀
地理科学 , 2001,
Abstract: 分析了现有灾异史料所覆盖时段(1803~1958年)西藏水灾的时空变化特征。研究指出①1803~1958年,西藏水灾发生(县)次数波动比较大;19世纪40~80年代为西藏的水灾多发期;1924、1954年为严重水灾发生年;②西藏水灾空间分布差异显著,主要分布在"一江两河"地区。其中,日喀则、山南地区的水灾(县)次最多,其次为拉萨市、林芝地区,昌都、阿里、那曲地区则水灾发生相对较少;③高强度的持续降水为西藏水灾发生的关键诱导因子,河流暴涨、漫溢、改道为重要媒体,山崩、雪崩、山洪及泥石流等要素为特定地貌条件下的主要致灾因子,雹灾、地水上涌等也是不容忽视的致灾因子;④19世纪40~80年代西藏气候湿润。
鄱阳湖湿地植被退化原因分析及其预警
,,刘成
长江流域资源与环境 , 2015, DOI: 10.11870/cjlyzyyhj201503005
Abstract: 2003年以来,鄱阳湖长期处于低枯水位状态,湖盆植被面积减少600km2;洲滩土壤含水量降低,旱生植物物种入侵,占据高程15m以上洲滩,湿地植被演变成中生性草甸,使物种大幅度增加;湿生和水生植物向湖中心下移,生长空间缩减;对水深、污染物敏感的植物群落的物种、生物量减少,生物多样性退化;对水深适应性强和耐污染的植物迅速扩张。无序采砂、防火烧荒、牲畜放牧加剧了这一局面。在气候变化和人类活动影响下,鄱阳湖湿地植被正在逐步退化。为了遏制这一退化现象,正在建立鄱阳湖健康评价体系与标准,加强植物群落固定断面和针对稀有物种、对水深和污染物敏感物种、危害湖泊健康物种进行专项监测,针对发现的问题,用遥感影像辨识、实地勘测研究分析全湖变化状况,判断其危害程度,提出防治对策,向相关部门和地区提出预警建议
Page 1 /167837
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.