2219铝合金FSW/VPPAW交叉接头组织和性能

通过沿垂直于搅拌摩擦对接焊缝的方向进行变极性等离子弧对接立焊获得交叉焊缝,研究了6mm厚的2219铝合金交叉焊缝的微观组织和拉伸性能.并利用扫描电镜对焊缝断口的形貌进行了观察.结果表明,交叉焊缝呈现出铸态组织的特征,但是与单纯变极性等离子弧焊焊缝相比组织更不均匀.交叉焊缝的力学性能具有方向性,沿变极性等离子弧焊方向抗拉强度为254.5 MPa,沿搅拌摩擦焊方向的性能是207.53MPa,仅为母材的50%,满足使用要求.气孔是造成焊缝性能降低的主要原因.     

基于图谱法的新型运动分岔并联机构型综合

多模式并联机构在航空航天、机械加工、医疗康复等领域均极具应用前景,但目前能够实现多模式的运动分岔并联机构类型较少,绝大多数运动分岔并联机构中含有变自由度性质的RER支链,为此基于图谱法综合了一类新型运动分岔并联机构且机构中含有4类变自由度性质支链与已有的RER支链不同。首先基于图谱法以机构初始位置两瞬时转动自由度线非共面且相互垂直为例对2T1R运动分岔并联机构进行综合,随后将机构含有的URR支链中和定平台相连接的R副轴线方向改变,使其具有2R2T和3R1T两种自由度性质。将改进后的URR支链配置方案应用到部分4自由度和5自由度支链中,提出另外三类变自由度支链,每种类别支链分别有4、12、32种。以机构中含有4类不同变自由度性质的支链为分类依据,综合出四大类同时具有2T1R+2R1T两模式新型运动分岔并联机构,共包括12种子类别;以第4类变自由度支链为例,将其引入到并联机构中,通过图谱法综合出具有3T1R+2R2T两模式新型运动分岔并联机构。     

元青花《昭君出塞》罐艺术特征与主题思想研究

"昭君出塞"故事源于汉代,绵延流传,元青花《昭君出塞》罐表现的即为"昭君出塞"故事题材。元青花《昭君出塞》罐具有鲜明的艺术特征,同时,亦具有丰富而深邃的主题思想内涵。     

Poly(4,4'-bis(thien-2-yl)azobenzene-co-3-hexylthiophene): Synthesis and optical/electrochemical properties

A conjugated polymer of poly(4,4'-bis(thien-2-yl)azobenzene-co-3-hexylthiophene)(PTAB-H), bearing azo group in main chain and soluble in THF, chloroform, was synthesized through FeCl_3 oxidation copolymerization with 3-hexylthiophene, and the monomer of 4,4'-bis(thien-2-yl)azobenzene was synthesized by Sandmeyer reaction and Suzuki reaction. The UV-Vis spectra of PTAB-H reveal that azo group in the main chain can extend the absorption and lower the band gap. The fluorescent spectra, photoluminescence(PL) spectra, cyclic voltammetry(CV) of PTAB-H were recorded.The gel permeation chromatography(GPC), thermogravimetry analysis(TGA), and differential scanning calorimetry(DSC) measurements indicated that the molecular weight Mn, Mw and polydispersity indices(PDI) of the polymer are 10876 g/mol, 22338 g/mol and 2.05 respectively and the temperature of 5% weight-loss is 224.6 ℃. No glass transition and crystallization melting peak was observed in the temperature range from 30 ℃ to 400 ℃.     

Reconstituted yogurt from yogurt cultured milk powder mix has better overall characteristics than reconstituted yogurt from commercial yogurt powder

For manufacture of commercial yogurt powder, yogurt has to go through a drying process, which substantially lowers the yogurt culture counts, so the potential health benefits of the yogurt culture bacteria are reduced. Also, upon reconstitution, commercial yogurt powder does not taste like yogurt and has an off-flavor. The objective was to study the microbial, physicochemical, and sensory characteristics of reconstituted yogurt from yogurt cultured milk powder (YCMP) mix and reconstituted yogurt from commercial yogurt powder (CYP). The CYP reconstituted yogurt was the control and YCMP mix reconstituted yogurt was the treatment. Microbial and physicochemical characteristics of the CYP reconstituted yogurt and YCMP mix reconstituted yogurt were analyzed daily for the first week and then weekly for a period of 8 wk. Sensory consumer testing of CYP reconstituted yogurt and YCMP mix reconstituted yogurt was conducted with 100 consumers. At 56 d, YCMP mix reconstituted yogurt had 5 log cfu/mL higher counts of Streptococcus thermophilus than the control (CYP reconstituted yogurt). Also, Lactobacillus bulgaricus counts of YCMP mix reconstituted yogurt were 6.55 log cfu/mL at 28 d and were 5.35 log cfu/mL at 56 d, whereas the CYP reconstituted yogurt from 28 d onwards had a count of <10 cfu/mL. The YCMP mix reconstituted yogurt also had significantly higher apparent viscosity and sensory scores for appearance, color, aroma, taste, thickness, overall liking, consumer acceptability, and purchase intent than CYP reconstituted yogurt. Overall, YCMP mix reconstituted yogurt had more desirable characteristics than CYP reconstituted yogurt.     

介入治疗烧伤后下肢深静脉血栓形成13例

【摘要】 目的 探讨烧伤后下肢深静脉血栓形成（DVT）患者介入治疗效果及其特殊性。方法 回顾性分析13例烧伤并发下肢DVT患者临床资料。其中男7例，女6例；年龄37～67岁，中位年龄46.1岁；火焰伤9例，电击伤2例，热液伤2例；烧伤面积为1%～88%，平均（37.08±30.60）%；11例伴发下肢烧伤，其中8例双下肢烧伤；5例伴发吸入性损伤；烧伤后13～72 d发现DVT，平均（38.69±16.83） d。所有患者均接受介入治疗并观察疗效。结果 介入手术技术均获成功（13/13）。3例经右侧颈内静脉入路，10例经健侧股静脉入路分别接受下腔静脉滤器（IVCF）置入及抗凝治疗；7例留置溶栓导管接受接触溶栓，4例静脉溶栓，2例未溶栓治疗。未发生有症状的肺栓塞。介入治疗有效率为84.6%（11/13）。结论 介入治疗烧伤后DVT安全、可靠，但在穿刺点选择、是否留置溶栓导管方面有其特殊性。

     

企业加强质量管理和提高经济效益的几点思考

主要阐述了质量管理对企业发展的意义,针对企业在质量管理方面存在的问题,提出了注重人才队伍建设、建立质量管理体系、注意管理目标等强化企业经济效益、提升质量管理的建议,以提升企业的综合竞争力。     

吕临线建设项目压覆重要矿产资源评估

以山西吕梁至临县铁路支线建设项目为例,结合建设项目所在地概况,对该建设项目压覆重要矿产资源储量进行了系统评估,指出该建设项目具有较强的抗风险能力,从经济角度分析是可行的。     

First-principles study of doping and distribution of Si in TiC

In this work, first principles calculations have been performed to study the doping and distribution of Si atoms in TiC lattice. The results confirm that Si atoms prefer to occupy Ti sites and their segregation on the TiC crystal surface may occur. But in the presence of carbon vacancies on the surface, Si atoms tend to be chemically adsorbed around the vacancies rather than occupy the carbon sites. It is also shown that the diffusion of Si may be very difficult in stoichiometric TiC, in particular the diffusion from bulk to surface. However, the carbon vacancies can considerably decrease the energy barrier and enhance the diffusion of Si atoms.