Early Age Shrinkage and Mechanical Effect of Ultra-High-Performance Concrete Composite Deck: A Case Study with In Situ Test and Numerical Simulation

For the Honghe Bridge project located in Yunnan Province, Southwest China, a steel/ultrahigh-performance concrete (UHPC) composite deck is used in the suspension bridge with a 700 m main span, and the steel stud connectors are used in the 50 mm–thick UHPC layer. To investigate the shrinkage behavior of UHPC and the relevant influence, the in situ time-dependent strain is measured continuously, and within the 20-day curing time, the material behavior is summarized based on test results. This paper proposes a prediction model for UHPC shrinkage which is refined from the widely used B3 model for normal concrete material, and the parameter values are modified and optimized by experimental comparison. Combining the numerical model and the finite element analysis model of the composite deck, the detailed mechanical state in structural parts is studied. For the practical construction, the simulation results indicate that the small thickness of UHPC above the stud and weak bond strength can influence the eventual structural performance greatly. In the discussion of stress distribution at different locations of the deck, the potential crack on the edge and the corner of the UHPC–steel interface and the mechanical damage on the stud connector around are also indicated.     

鸦胆子茎节组培快繁体系的建立

目的：建立鸦胆子茎节组培快繁体系。方法：选用鸦胆子嫩枝为外植体,探讨基本培养基和外源激素对其离体再生的初代培养、继代增殖、生根培养的影响,并进行移栽试验。结果：鸦胆子的不定芽增殖、壮苗、生根的最佳培养基分别为MS＋6-BA1．0mg·L^-1＋IBA0.1mg·L^-1,1／2MS＋香蕉汁20g·L^-1;1／2NS＋IBA0．1mg·L^-1＋NAA0．1mg·L^-1。炼苗基质为细沙时,成活率最高。     

圆叶牵牛毛状根的诱导及培养

目的：利用发根农杆菌,R1601,1000,1025,15834诱导约用植物圆叶牵牛产生毛状根。方法：采用共培养方法,通过对外植体、菌种、浸染时间、预培养、共培养、外源激素等因素对转化率的影响。结果：利川发根农杆菌1601,预培养60h的叶片、叶柄为转化材料,感染6～8min,加入1mg·L^-1 NAA转化率最高。结论：圆叶牵牛毛状根的诱导成功,为其遗传转化提供了依据。     

子宫内膜异位症与抗碳酸酐酶抗体的关系

目的 :探讨抗碳酸酐酶Ⅰ、Ⅱ抗体与子宫内膜异位症的关系。方法 :应用酶联免疫吸附 (ELISA)法分别检测内异症 32例、其他妇科疾病 (妇科组 ) 2 0例及正常妇女 12例血清抗碳酸酐酶抗体水平。结果 :(1)内异症患者血清抗碳酸酐酶Ⅰ、Ⅱ抗体阳性率(87.5 %、5 3.1% )高于妇科组 (2 5 %、15 % ) ,两组差异有显著性 (P <0 .0 1) ;(2 )内异症患者血清抗碳酸酐酶Ⅰ、Ⅱ抗体阳性率明显高于正常妇女组 (0 %、0 % ) ,两组差异有显著性 (P<0 .0 1) ;(3)妇科组及正常妇女组血清抗碳酸酐酶Ⅰ、Ⅱ抗体阳性率较低 ,两组差异无显著性 (P >0 .0 5 )。结论 :检测抗碳酸酐酶抗体对诊断子宫内膜异位症及探讨其发病机制有重要价值     

HPLC法测定齿囊耙齿菌固体发酵产物中麦角甾醇含量

目的建立齿囊耙齿菌固体发酵产物中麦角甾醇含量的测定方法。方法采用高效液相色谱方法,汉邦ODS-C18色谱分析柱(250×4.6mm,5μm),流动相为100%甲醇,流速1.0m L/min,检测波长282nm;柱温30℃。结果麦角甾醇进样量在0.20~1.40μg之间与吸收峰面积呈良好的线性关系,r=0.9999;平均加样回收率为100.07%,RSD(%)=1.91%。方法具有较高的专属性、准确性、重现性和可行性。结论该方法简便、准确、灵敏度好,为齿囊耙齿菌固体发酵产物质量评价提供了可靠依据。     

累积空腹血糖暴露对心脑血管事件的影响

目的 探讨累积空腹血糖暴露(cumFBG)对心脑血管事件的影响。方法 采用前瞻性队列研究方法,以连续参加2006-2007、2008-2009、2010-2011年3次健康体检的开滦集团职工为观察对象,排除心肌梗死、脑卒中、心力衰竭患者,最终纳入统计分析52 980例。以观察对象完成第3次健康体检时间为随访起点,以发生心脑血管事件为终点事件,随访终止时间为发生心脑血管事件、全因死亡或末次随访时间(2017年12月31日)。按cumFBG四分位分组,用Kaplan-Meier法计算各组心脑血管事件累积发病率,并用Log-rank检验比较各组心脑血管事件累积发病率的差异;采用Cox比例风险模型分析cumFBG对心脑血管事件的影响。结果 随访(6.76±1.03)年,cumFBG第1至第4四分位组心脑血管事件发病密度分别为3.42/千人年、4.57/千人年、5.68/千人年和9.53/千人年,且随着cumFBG增加,心脑血管事件、脑卒中、缺血性脑卒中累积发病率均呈上升趋势,经Log-rank检验及组间两两比较,差异有统计学意义(均P<0.01)。Cox比例风险模型显示校正年龄、性别、体...     

探讨低剂量索他洛尔与普罗帕酮治疗心律不齐的效果

目的 探讨低剂量索他洛尔与普罗帕酮治疗心律不齐的效果.方法 选取2017年4月至2019年8月于本院治疗的60例心律不齐患者为研究对象,随机分为对照组和观察组,各30例.对照组使用普罗帕酮进行治疗,观察组使用低剂量索他洛尔进行治疗.比较两组治疗效果,检测治疗前后QT离散度数据,记录治疗期间药物不良反应发生情况.结果 观...     

丁甘仁辨治哮喘思路探析

丁甘仁为孟河四大家的杰出代表,著名的中医临床家、教育家,其著录的《丁甘仁医案》一书,充分反映了丁甘仁诊疗临床各科之经验。《丁甘仁医案》卷四记录14例哮喘医案,可归纳丁甘仁对哮喘的辨治思路：治疗兼顾内外,疏外邪、化内饮以止咳喘,注重调理脏腑气机,重纳肾气、健脾气、降肺气以止咳喘;用药上多选温药化痰,以脾肺肾经药为主,善用鹅管石治喘急,海浮石化老痰,半夏配茯苓杜生痰之源,补骨脂配五味子治肾虚不纳,远志利肺气纳肾气;组方上采撷众方,汤丸并用。     

无创高频通气对新生儿呼吸衰竭血气、生命体征及并发症的影响

目的：研究无创高频通气对新生儿呼吸衰竭血气、生命体征及并发症的影响。方法：将医院新生儿重症监护室(NICU)2017年1月～2018年5月间收治的106例新生儿呼吸衰竭患儿采用随机数字表法均为分高频通气组(无创高频通气,n=53)与传统组[经鼻间歇正压通气(NIPPV),n=53],比较两组治疗效果。结果：治疗前、治疗3h及12h后,两组血气分析指标PaO₂、PaCO₂、SaO₂均发生显著性改变,PH水平均无显著性改变,其中高频通气组治疗12h后,PaO₂水平明显高于传统组同时间段水平,高频通气组治疗3h及12h后PaCO₂及显著低于传统组同时间段水平,SaO₂高于传统组同时间段水平;治疗前、治疗3h及12h后,两组生命体征MAP、HR及T水平均无显著性改变,两组治疗期间呼吸频率均呈下降趋势,且高频通气组治疗3h及12h后,呼吸频率均显著低于传统组同时间段水平;高频通气组治疗并发症发生率显著低于传统组;高频通气组治愈率显著高于传统组,两组放弃治疗及死亡率均...     

The Effect of Acidity Coefficient on the Crystallization Properties and Viscosity of Modified Blast Furnace Slag for Mineral Wool Production

The crystallization and viscosity of modified blast furnace slag are key factors in fiber forming conditions. In this paper, the crystallization behavior of modified blast furnace slag under continuous cooling conditions was studied by differential scanning calorimetry, and its crystallization kinetics with different acidity coefficients were established. On this basis, the evolution law of the crystallization phase and the influence of crystallization on the viscosity of modified blast furnace slag with different acidity coefficients were analyzed. The results indicated that the crystallization phases of slag with acidity coefficients of 1.05 and 1.20 were, respectively, Melilite and Anorthite. During the cooling process at the acidity coefficient of 1.05, the critical rates of precipitation of Melilite and Anorthite were 50 °C/s and 20 °C/s, respectively, while they were 20 °C/s and 15 °C/s, respectively, at the acidity coefficient of 1.20. With the increase of the acidity coefficient, the crystal growth mode of slag changed from two-dimensional and three-dimensional mixed crystallization to surface nucleation and one-dimensional crystallization. The crystallization activation energy of slag with acidity coefficients of 1.05 and 1.20 were 698.14 kJ/mol and 1292.50 kJ/mol, respectively. In addition, the change trend of viscosity was related to crystal size and content.