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Search Results: 1 - 10 of 24113 matches for " 魏倩倩 "
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基于背散射电子图像的矿渣-水泥复合体系反应程度的定量分析
倩倩,
硅酸盐学报 , 2015, DOI: 10.14062/j.issn.0454-5648.2015.05.03
Abstract: 采用基于背散射电子图像(BSE)的物相灰度定量分析法研究了矿渣-水泥复合体系中水泥、矿渣各自反应程度及总体
SiC陶瓷/金属钨的SPS扩散焊接
Diffusion Welding SiC Ceramic/Tungsten by SPS
 [PDF]

张金咏, 倩倩, 张帆, 王玉成, 傅正义
Material Sciences (MS) , 2013, DOI: 10.12677/MS.2013.31002
Abstract:
本文采用放电等离子烧结(SPS)技术,对用于高温环境下服役的SiC陶瓷扩散焊接进行了探索研究。结果表明,采用SPS技术可以在1300~1500实现SiC/W的连接。在SPS扩散焊接条件下SiCW在界面处会发生化学反应,形成一个主要组分为WCSi3W5等新相的过渡层,且随着焊接时间延长和温度升高,W持续向SiC层扩散在过渡层和SiC的界面上形成新的反应物,从而导致过渡层的厚度增加。过渡层的厚度对焊接件性能的影响呈现非线性变化,对焊接件的三点弯曲强度测试表明:在1410时,保温5 min,材料在界面处的弯曲强度达到最高,约162 MPa。对焊接后金属钨的结构分析显示,高温过程对钨的微结构没有明显的改变,断裂方式仍为延性断裂。显然,SPS可以成为一种快速、有效的SiC陶瓷/金属W扩散焊接
季铵型阳离子淀粉絮凝剂的制备及其应用
倩倩,童群义
化工进展 , 2010,
Abstract: 以玉米淀粉为原料,3-氯-2-羟丙基三甲基氯化铵为阳离子醚化剂,采用预干燥干法制备高取代度季铵型阳离子淀粉絮凝剂。考察了醚化剂用量、氢氧化钠与醚化剂摩尔比、反应温度及反应时间对取代度和反应效率的影响,优化出制备高取代度阳离子淀粉的最佳工艺条件为醚化剂的加入量为绝干淀粉量的55%,氢氧化钠与醚化剂摩尔比为1.2,反应温度85℃,反应时间4h。将阳离子淀粉对工业中较难处理的高色值糖蜜酒精废液进行絮凝脱色性能测定,结果表明当阳离子淀粉质量浓度为500mg/L、取代度为0.39、废液初始pH值为9.0时,脱色率达53.6%。
菊粉对肉仔鸡生长性能、免疫器官指数及抗氧化指标的影响
轶男?,倩倩,吕亚军?
西北农林科技大学学报(自然科学版) , 2013,
Abstract: 【目的】研究菊粉对1~42日龄肉仔鸡生长性能、免疫器官发育及抗氧化能力的影响。【方法】选用1日龄健康科宝肉鸡280只,随机分为4组,每组7个重复,每个重复10只鸡,分别饲喂含质量分数0(对照),0.5%,1.0%和1.5%菊粉的饲粮,饲养期为42d,试验期间记录每天的采食量,分别于试验开始的1,7,14,21,28,35和42d早晨以重复为单位空腹称体质量,计算平均日采食量、平均日增质量和料体质量比;分别于21和42d取样测定肉仔鸡免疫器官指数及肝脏和血清中的抗氧化指标。【结果】与对照组相比,日粮中添加菊粉对1~42日龄肉仔鸡的生长性能无显著影响(p>0.05),但有提高平均日增质量、平均日采食量和降低料体质量比的趋势;添加菊粉可显著提高1~42日龄肉仔鸡的脾脏、胸腺和法氏囊指数(p<0.05),其中以添加质量分数为1.0%和1.5%时效果较好;添加菊粉可显著降低1~42日龄肉仔鸡肝脏和血清的mda含量,并可显著提高t-sod、gsh-px含量(p<0.05),其中以添加菊粉的质量分数为1.0%时效果较好。【结论】菊粉有促进肉仔鸡生长、提高肉仔鸡免疫器官指数和抗氧化能力的作用,其中以质量分数为1.0%的添加量效果较好。
水泥混凝土路面板固化温差对翘曲和应力的影响
Effect of built-in temperature difference on curling and stresses in cement concrete slabs

,梁思明,倩倩
- , 2015, DOI: 10.11835/j.issn.1674-4764.2015.01.014
Abstract: 实测硬化中水泥混凝土路面板内的温度分布,确定混凝土的终凝时间,提出固化温差及有效温差的计算方法,并计算两种施工环境条件下路面板的固化温差和有效温差,进行固化温差对板的翘曲和应力影响分析计算。研究结果表明:春季和秋季施工在水泥混凝土路面板中产生负的固化温差,将会导致路面板在1 d中的大部分时间处于板中脱空的状态,在板中临界荷位处板底产生拉应力,而采用小尺寸板,相比较大尺寸板更能降低路面板翘曲及耦合应力,降低疲劳破坏。
The temperature distributions were measured in hardening concrete slabs, determining final set time of concrete; the calculation methods of built-in temperature difference and the effective temperature difference were provided to determine the corresponding values of the slabs constructed during spring and fall, respectively. Finally, the influence of built-in temperature difference on slab curling and stress were evaluated based on finite element analysis. The results show that negative built-in temperature differences were found in both spring and fall construction which will lead to loss of slab support in the mid-slab position during the most time of a day, and larger tensile stress generates at the slab bottom. However, small size slab will minimize this negative effect from built-in temperature difference and at the same time reduce fatigue damage.
CGM与SMBG改善1型糖尿病患者血糖控制及减少低血糖事件发生的meta分析
美林,倩倩,韩峻峰,
- , 2015, DOI: 10.16118/j.1008-0392.2015.05.017
Abstract: 目的 探讨动态血糖监测(continuous glucose monitoring, CGM)与自我血糖监测(self-monitored blood glucose, SMBG)改善1型糖尿病患者血糖控制及减少低血糖事件发生的效果。方法 检索国内外各类大型数据库自建库以来发表的关于应用CGM对比SMBG的临床随机对照试验(randomized controlled trial, RCT),采用meta分析的方法,利用stata 12.0软件评价应用CGM对比SMBG的效果。结果 与SMBG相比,1型糖尿病患者应用CGM能够有效降低糖化血红蛋白(HbA1c)(WMD: -0.23%,95%CI: -0.29~-0.16)。亚组分析显示,应用动态血糖监测能降低成人(WMD: -0.33%,95%CI: -0.46~-0.20)及儿童、青少年(WMD: -0.13%,95%CI: -0.26~-0.01)1型糖尿病患者糖化血红蛋白值。实时动态血糖监测(real-time CGM)可有效改善血糖控制(WMD: -0.23%,95%CI: -0.30~-0.16)。应用CGM可减少低血糖事件发生(SMD: -0.27,95% CI: -0.45~-0.09)。结论 动态血糖监测,特别是实时动态血糖监测可有效改善1型糖尿病患者的血糖控制,减少低血糖事件发生。
Objective To compare continuous glucose monitoring(CGM) with self-monitored blood glucose(SMBG) in glucose control and reducing hypoglyemic episodes in patients with type 1 diabetes. Methods We searched major international and domestic databases up to August 2014 for randomized controlled trials comparing CGM and SMBG in type 1 diabetes. Meta-analysis was performed by stata 12.0 software. ResultsPatients using CGM had a greater decrease in HbA1c from baseline compared with those using SMBG(WMD: -0.23%, 95%CI: -0.29--0.16). We found that it was effective both for adults(WMD-0.33%, 95%CI: -0.46--0.20) as and children/adolescents(WMD: -0.13%,95%CI: -0.26--0.01). Only real-time devices for CGM improved glycemic control(WMD: -0.23%,95%CI: -0.30--0.16). Pooled results from 5 studies revealed a reduction in hypoglycemic events in the CGM group(SMD: -0.27,95%CI: -0.45--0.09). Conclusion CGM, particularly real-time system, has a favorable effect on glycemic control and reducing hypoglycemic episodes in patients with type 1 diabetes
从创伤理论视角看电影《喜福会》中的创伤与疗伤
Trauma and Therapy in the Film The Joy Luck Club from the Perspective of Trauma Theory
 [PDF]

倩倩
World Literature Studies (WLS) , 2015, DOI: 10.12677/WLS.2015.34022
Abstract:
电影《喜福会》是一部家喻户晓的影片,近年来对于此作品的研究摆脱不了“东西文化冲突”、“女性主义”、“母女关系”等字眼,本文试图从创伤理论视角全面分析电影中母女的创伤,探讨创伤的来源并寻找疗伤的途径,希望读者从创伤理论视角对影片产生更为深刻的理解,也为华裔女性医治创伤提供借鉴。
The film The Joy Luck Club was a well-known film made on the basis of the novel of the same name. Recent studies mainly focus on the oriental and occidental cultural conflicts, feminism or relationship between mother and daughter. This paper tries to analyze the traumas of the four mothers and their daughters, the reasons for their traumas and possible means to cure traumas from the perspective of trauma theory in order to make readers have a profound understanding about the film and provide reference for Chinese-American women to cure their traumas in real life.
运用MEPDG建立季冻区水泥路面IRI预测修正模型
倩倩,程培峰,玉伟,周兴业
- , 2018, DOI: 10.11918/j.issn.0367-6234.201709056
Abstract: 为解决季冻区水泥路面平整度预测问题,基于MEPDG构建了季冻区水泥路面国际平整度指数(IRI)预测修正模型.该模型充分考虑了交通状况、气候条件和道路各层材料的特性,在原有预测模型基础上对CRK、TFAULT、SPALL和SF 4个指标变化趋势进行分析并与IRI相关性进行了验证,利用SPSS分析软件提出适用于季冻区特点的水泥路面平整度指数预测修正模型,结合黑龙江省水泥路面调查数据进行验证.结果表明:气候、交通、材料参数均对构成预测国际平整度指数的4个指标CRK、TFAULT、SPALL和SF有显著影响;且4个指标和国际平整度指数线性拟合可靠度高;利用交通量、降水、降雨、潮湿天数、冻融循环次数,路面材料性能等参数可对季冻区水泥路面国际平整度指数进行预测.提出的预测修正模型预测的精确度高,具有良好的实用性和较高的预测性能.
To solve the problem of flatness prediction of cement pavement in seasonal frozen region, the international roughness index (IRI) prediction revised model of cement pavement in frozen season was constructed using MEPDG. The model takes into account the traffic conditions, climatic conditions, and the characteristics of the materials of the pavement layers. The trends of CRK, TFAULT, SPALL, and SF were analyzed and verified with IRI correlation on the basis of the original prediction model. SPSS analysis software was used to obtain the prediction revised model of cement pavement roughness index in seasonal frozen region. The cement pavement survey data of Heilongjiang Province was used to verify this model. The results show that climate, traffic, and material parameters had significant influence on the four indexes CRK, TFAULT, SPALL, and SF. These indicators and international flatness index were linearly fitted with high reliability. The number of traffic, precipitation, rainfall, wet days, the number of freeze-thaw cycles, and the performance of pavement materials can be used to predict the international flatness index of cement pavement in seasonal frozen region. The accuracy of the model was high, with good practicability and high predictive performance.
中国青藓科植物分类学修订(Ⅱ):燕尾藓属
,,倩倩,王晓蕊,王幼芳
- , 2016,
Abstract: 基于燕尾藓属(Bryhnia Kaurin)被处理为狭义青藓属(Brachythecium Schimp. s. str.)的异名,燕尾藓属已不复存在。笔者对原分布于中国的5种燕尾藓属植物进行了相应的分类学修订,结果如下:短尖燕尾藓(B. hultenii E. B. Bartram)、燕尾藓[B. novae angliae (Sull. & Lesq.) Grout]和毛尖燕尾藓(B. trichomitria Dixon & Thér.)被移入狭义青藓属并处理为短尖青藓[Brachythecium hultenii (E. B. Bartram) Min Li & Y. F. Wang]、燕尾青藓[B. novae angliae (Sull. & Lesq.) A. Jaeger]和东亚青藓[B. trichomitrium (Dixon & Thér.) Huttunen, Ignatov, Min Li & Y. F. Wang];短枝燕尾藓(B. brachycladula Cardot)被移入鼠尾藓属(Myuroclada Besch.),并处理为羽枝鼠尾藓[M. longiramea (Müll. Hal.) Min Li, Y.F. Wang, Ignatov & Huttunen]的异名;密枝燕尾藓[B. serricuspis (Müll Hal.) Y. F. Wang & R. L. Hu]移入拟异叶藓属(Pseudokindbergia Min Li, Y.F. Wang, Ignatov & B.C. Tan),并处理为拟异叶藓[P. dumosa (Mitt.) Min Li, Y.F. Wang, Ignatov & B.C. Tan]的异名。
Cn上φ-闭正流的Lelong数
The Lelong Number of a φ-Positive Closed Current on Cn
 [PDF]

王芳,倩倩
Pure Mathematics (PM) , 2016, DOI: 10.12677/PM.2016.62015
Abstract:
本文给出了Cn上φ-闭正流ddφf的Lelong数,这里φ是特殊Lagrangian calibration,f是Lloc1(Cn)中的φ-多次下调和函数。并且我们应用此Lelong数,将单复变中全纯函数的极小模原理进行了推广,给出了此类φ-多次下调和函数的一个下界估计。
In this paper, we give the Lelong number of a φ-positive closed current ddφf , where φ is the special Lagrangian calibration and f is a φ-plurisubharmonic function in Lloc1(Cn)?. Using that Lelong number, we generalize the minimum modulus principle for the holomorphic function of one complex variable, and we get an estimate of the low bound for φ-plurisubharmonic functions.
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