垂体后叶素联合宫腔水囊在近子宫内口处胎盘源性难治性产后出血时应用

目的评价垂体后叶素联合宫腔水囊填塞在剖宫产术中近子宫内口处胎盘源性难治性产后出血时的止血效果。方法选择剖宫产术中近子宫内口处难治性出血经常规处理不能止血的18例患者,应用胎盘剥离面多点注射垂体后叶素联合填塞宫腔水囊。结果 18例患者均成功止血,无子宫切除,无孕妇死亡。结论垂体后叶素联合宫腔水囊填塞是控制近子宫内口处胎盘源性难治性产后出血的有效方法,值得临床推广。

云南中学生对成瘾性处方药滥用的认知调查

对云南省部分地区在校中学生进行了成瘾性处方药滥用的相关知识问卷调查,为制定成瘾性处方药滥用预防教育方案和方法提供依据。方法:自行设计成瘾性处方药调查问卷,对云南省7个州市的初一至高三学生进行问卷调查。结果:共发放问卷2913份,有效问卷2611份,占89.63%。结论:云南中学生对成瘾性处方药知识了解甚少,存在滥用成瘾性处方药的隐患,应引起相关部门重视,加强成瘾性处方药滥用的预防教育。

强夯法在电厂湿陷性黄土地基处理中的应用

对山西省某电厂地基强夯法处理湿陷性黄土地基的经验做了介绍 ,主要包括在强夯施工过程中的强夯试验、施工方案的选择及施工过程中的具体问题及其处理效果 。

微表处在公路路面预防性养护中的应用

微表处技术具有施工方便、开放交通快、可有效修复车辙、维修成本低、节能环保等特点,在公路路面预防性养护中有着较广泛的应用。结合自身工作经验,重点对微表处混合料配合比设计及施工要点进行了重点分析,在某高等级公路路面预防性养护中应用,收到了良好的经济和社会效益,值得推广。

湿陷性地基处理方案技术经济比较

对强夯、灰土挤密桩处理方案在章丘电厂冷却塔湿陷性地基处理方面的应用进行了技术经济比较 ,分析了两种方案各自的优。

近断层地震动作用下钢筋混凝土桥墩的抗震性能

通过对满足规范延性要求的12根典型钢筋混凝土桥墩试件的线性和非线性地震反应分析,指出在近断层地震动作用下满足延性需求与延性能力比小于1 0的桥墩仍可能发生严重破坏和倒塌,若考虑桥墩的地震损伤性能,允许的延性需求与延性能力比不宜超过0 6～0 8。讨论了桥墩延性抗震设计中强度折减系数Rμ和设计基底剪力系数BSC取值问题。

公路工程微表处预防性养护施工技术的应用

作为预防性养护新技术,微表处预防性养护施工技术有着诸多有点,其兼备较快的施工速度、污染小、适用范围广等特点。为了进一步全面发挥出微表处预防性养护技术的优势,相关工作人员需要对相关技术要点进行深入地了解和掌握,有效控制施工质量,延长公路工程的使用寿命。

强夯法在湿陷性黄土地基处理中的应用研究

我国西北地区黄土地质范围广泛,应用湿陷性黄土地基处理技术能够强化地基结构的稳定性。基于此,本文就强夯法技术原理及应用优势进行了分析,并结合某工程案例探讨了湿陷性黄土地基强夯技术的应用方法。

湿陷性黄土地基处理强夯法

南水北调中线工程禹州长葛段第五标段总干渠渠堤湿陷性黄土地基处理工程量大．沿线制约因素多，技术性较强。为确保总干渠的安全与正常使用，项目部采取了强夯法施工工艺处理地基湿陷性，作为施工便捷、工艺成熟、经济易行、节省材料的地基处理方法之一，在南水北调工程地基处理中广泛应用。且强夯法施工工艺也是处理地基湿陷性的典型。文章重点介绍了强夯法消除地基湿陷性的施工工艺、施工要点及注意事项。

强夯法在高原机场湿陷性黄土地基处理中的应用——以新疆昭苏机场二标段项目为例

介绍在昭苏机场项目中开展强夯法处理湿陷性黄土,强夯处理后经现场取不同深度湿陷性土样检测,湿陷性粉土层湿陷性指标均满足设计要求。

MS-3型微表处在高速公路预防性养护中的应用

以广东西部沿海高速公路为依托,对MS-3型微表处在该工程中的配合比设计作了介绍,阐明了微表处施工的工艺流程、技术要点及现场补给工艺,并对微表处后的路面性能进行了检测,指出该路面的抗滑性与封水性均达到了预防性养护要求。

如何处理好历史学习的拓展

进行课外拓展是新课程理念的要求,也是时代发展的要求。但是教师的拓展要避免随意性,遵循以文本为基础,遵循适度的原则。并且对文本的拓展要能够引起学生的共鸣,还要遵循遵循适时性原则。从而在丰富课堂学习的同时,起到优化教学的效果。

微表处施工技术与质量控制研究

近年来,微表处技术在国内外广泛应用于公路路面的预防性养护中,结合高速公路微表处养护施工的实践,介绍微表处混合料施工工艺、施工注意事项及质量控制等。

双抗减少颅内动脉多处中度狭窄脑梗死复发的疗效研究

目的:总结症状性颅内动脉多处中度狭窄患者采取阿司匹林联合氯吡格雷进行治疗的疗效。方法:选取某院2016年6月~2017年5月收治的急性脑梗死,并经MRA确诊颅内动脉多处中度狭窄的患者60例,随机分为对照组和实验组,对照组接受阿司匹林治疗,实验组在对照组基础之上加用氯吡格雷,分别采用秩和检验、t检验和χ^2检验比较实验组与对照组患者患者的疗效、治疗前后NIHSS评分及脑梗死复发率。结果:实验组患者疗效优于对照组,治疗后NIHSS评分低于对照组,症状性脑梗死复发率低于对照组,差异有统计学意义。结论:对于症状性颅内动脉多处中度狭窄患者,应用阿司匹林联合氯吡格雷治疗防止症状性脑梗死的复发效果理想,应该给予大力的推广与应用。

Effect of thermo-mechanical treatment on microstructure and mechanical properties of wire-arc additively manufactured Al-Cu alloy

Wire-arc additive manufacture(WAAM)has great potential for manufacturing of Al-Cu components.However,inferior mechanical properties of WAAM deposited material restrict its industrial application.Inter-layer cold rolling and thermo-mechanical heat treatment(T8)with pre-stretching deformation between solution and aging treatment were adopted in this study.Their effects on hardness,mechanical properties and microstructure were analyzed and compared to the conventional heat treatment(T6).The results show that cold rolling increases the hardness and strengths,which further increase with T8 treatment.The ultimate tensile strength(UTS)of 513 MPa and yield stress(YS)of 413 MPa can be obtained in the inter-layer cold-rolled sample with T8 treatment,which is much higher than that in the as-deposited samples.The cold-rolled samples show higher elongation than that of as-deposited ones due to significant elimination of porosity in cold rolling;while both the T6 and T8 treatments decrease the elongation.The cold rolling and pre-stretching deformation both contribute to the formation of dense and dispersive precipitatedθ′phases,which inhibits the dislocation movement and enhances the strengths;as a result,T8 treatment shows better strengthening effect than the T6 treatment.The strengthening mechanism was analyzed and it was mainly related to work hardening and precipitation strengthening.

类风湿性关节炎膝关节病变的X线影像学研究

目的 :分析类风湿性关节炎(RA)膝关节病变的X线影像学特征,以提高诊断正确率。方法 :收集2015年2月至2017年2月收治的RA患者52例和骨关节炎患者45例,进行X线摄片,分析两组膝关节病变的影像学特征。结果 :RA组中,关节间隙呈均匀性狭窄47例(90.4%),髌上囊肿胀41例(78.8%),关节面毛糙、关节面不同程度侵蚀破坏22例,关节周缘轻度骨质增生43例,明显重度增生、骨赘形成5例,未见明显骨质增生4例,52例均有不同程度骨质疏松。OA组中,关节间隙呈均匀性狭窄5例(11.1%),髌上囊肿胀16例(35.6%),关节面下小囊性改变7例,45例有不同程度骨质增生、骨赘形成改变。两组关节间隙均匀狭窄及髌上囊肿胀改变发生率差异有统计学意义(P<0.05)。结论 :RA膝关节病变的X线影像学表现具有一定特征性,尤其是关节间隙均匀性狭窄、髌上囊肿胀及关节面侵蚀的改变在鉴别RA和OA的诊断中有重要价值。

Influence of Zr content on microstructure and mechanical properties of implant Ti-35Nb-4Sn-6Mo-xZr alloys

The influence of Zr content on the microstructure and mechanical properties of implant Ti-35Nb-4Sn-6Mo-xZr （x=0, 3, 6, 9, 12, 15; mass fraction） alloys was investigated. It is shown that Ti-35Nb-4Sn-6Mo-xZr alloys appear to have equiaxed single β microstructure after solution treatment at 1023 K. It is found that the grains are refined first and then coarsened with the increase of Zr content. It is also found that Zr element added to titanium alloys has both the solution strengthening and fine-grain strengthening effect, and affects the lattice parameters. With increasing the Zr content of the alloys, the strength increases, the elongation decreases, whereas the elastic modulus firstly increases and then decreases. The mechanical properties of Ti-35Nb-4Sn-6Mo-9Zr alloy are as follows： σb=785 MPa, δ=11%, E=68 GPa, which is more suitable for acting as human implant materials compared to the traditional implant Ti-6Al-4V alloy.

Effect of heat treatment on microstructure and tensile properties of A356 alloys

Two heat treatments of A356 alloys with combined addition of rare earth and strontium were conducted.T6 treatment is a long time treatment（solution at 535 ℃ for 4 h ＋ aging at 150 ℃ for 15 h）.The other treatment is a short time treatment（solution at 550 ℃ for 2 h ＋ aging at 170 ℃ for 2 h）.The effects of heat treatment on microstructure and tensile properties of the Al-7%Si-0.3%Mg alloys were investigated by optical microscopy,scanning electronic microscopy and tension test.It is found that a 2 h solution at 550 ℃ is sufficient to make homogenization and saturation of magnesium and silicon in α（Al） phase,spheroid of eutectic Si phase.Followed by solution,a 2 h artificial aging at 170 ℃ is almost enough to produce hardening precipitates.Those samples treated with T6 achieve the maximum tensile strength and fracture elongation.With short time treatment（ST）,samples can reach 90% of the maximum yield strength,95% of the maximum strength,and 80% of the maximum elongation.

Effect of heat treatment on microstructures and mechanical properties of sand-cast Mg-4Y-2Nd-1Gd-0.4Zr magnesium alloy

Influence of heat treatment on the microstructures and mechanical properties of sand-cast Mg-4Y-2Nd-1Gd-0.4Zr magnesium alloy was investigated,and the tensile fracture mechanisms of the studied alloys under different conditions were also discussed.The results show that the optimum T4 and T6 heat treatment conditions for the as-cast Mg-4Y-2Nd-1Gd-0.4Zr alloy are 525°C,8 h and（525°C,8 h）＋（225°C,16 h）,respectively,with regard to the microstructure observation,DSC heating curve and mechanical properties.The hardness,yield strength,ultimate tensile strength and elongation of the Mg-4Y-2Nd-1Gd-0.4Zr alloy treated by optimum T6 heat treatment are HV91,180 MPa,297 MPa and 7.4%,respectively.Moreover,the Mg-4Y-2Nd-1Gd-0.4Zr alloys under different heat treatment conditions exhibit different tensile fracture modes.

Effects of heat treatment on microstructure and mechanical properties of ZK60 Mg alloy

The microstructure and mechanical properties of ZK60 Mg alloy were investigated under different solution treatments and artificial aging conditions. When as-cast ZK60 alloy was solution treated at 400 ℃for 10 h and artificially aged at 150 ℃, the volume fraction of precipitates increased with the aging time up to 30 h. When the as-cast ZK60 alloy was solution treated at 400 ℃ for 10 h and artificially aged at 200 ℃ for 15 20 h, the volume fraction of precipitates reached a peak value. Tensile test at room temperature showed that a high density of the second phase precipitates was beneficial to improving the strength and elongation. Solution treatment at 400 ℃ for 10 h and artificial aging at 150 ℃ for 30 h is considered the optimum heat treatment condition to obtain a good combination of strength and ductility.