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  • Effect of Aluminum Phosphate Sealing Treatment on Corrosion Resistance of Anodic Oxide Films on Al-alloys

    Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-31 Cooperative journals: 《腐蚀科学与防护技术》

    Abstract: Anodic oxide films on Al-alloys were sealed by aluminum phosphate to further improve their corrosion resistance. Electrochemical impedance spectroscope (EIS) was used to study the effect of the sealing treatment on corrosion resistance of the anodic oxide films in comparison with those sealed with boiling water and cerium salt solution respectively. The results showed that, the aluminum phosphate coating was formed on the anodic oxide film sealed with aluminum phosphate, and it could provide the anodic oxide film the best corrosion resistance superior to those sealed with boiling water and cerium salt solution. Furthermore, the effectiveness of the aluminum phosphate treatment could last longer than that of sealing treatmants with boling water and cerium salt solution. This method could be a new sealing treatment for anodic oxide film on Al-alloys.

  • Effect of Alloying Elements on Mechanical Property and Fracture Toughness of A7N01S-T5 Aluminum Alloy

    Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-18 Cooperative journals: 《材料研究学报》

    Abstract: The influence of alloying elements on mechanical property and fracture toughness of A7N01S- T5 aluminum alloy was investigated on the basis of impact test, tensile test and three point bending test. The results show that with a proper addition of the selected alloying elements such as Zn (4.34), Mg(1.43), Mn(0.27), Cr(0.13), Zr(0.12) and Ti(0.066), the A7N01S-T5 aluminum alloy possesses a comprehensive performance with tensile strength 415 MPa, yield strength 378 MPa, specific elongation 13.49%, impact energy 12.3 J and fracture toughness 28.950 kJ·m-2 respectively. It is noted that among others the content of Zn and Mg is the main factor influencing both the strength and ductility, therefore, which should be carefully chosen. It is observed that η´ phase precipitates in the grain interior and η phase precipitates discontinuously at grain boundaries for the A7N01S- T5 aluminum alloy with proper chemical composition.

  • 2000—2015年柴达木盆地植被覆盖度时空变化及其与环境因子的关系

    Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2019-09-11 Cooperative journals: 《干旱区地理》

    Abstract:基于MODIS-NDVI、DEM和气象数据,分析柴达木盆地2000—2015年植被覆盖度(FVC)时空变化特征,并与降水、温度、日照时数、相对湿度、蒸散量和海拔进行相关、偏相关或叠加分析,探讨FVC与各环境因子的关系。结果表明:FVC整体自东南向西北内陆呈半环状递减,FVC集中在20%以下,人类活动及径流等打破植被地带性规律;2000—2015年FVC明显改善,广泛分布于盆地中西部地区,2001—2002年年际变化最显著;FVC与降水、相对湿度以正相关为主,与温度关系不显著,与日照时数和蒸散量主要为负相关,降水对FVC贡献最大,温度通过影响蒸散量等间接影响FVC,而土壤蒸发对蒸散量的影响大于植物蒸腾;FVC与等高线空间分布较吻合,FVC在2 800~2 900 m和4 600~4 700 m出现两个峰值,4 700 m以上FVC迅速降低。

  • 大午粉1号商品代蛋鸡育成后期(10~17周龄)饲粮中适宜代谢能和蛋白质水平的研究

    Subjects: Biology >> Zoology submitted time 2018-12-25 Cooperative journals: 《动物营养学报》

    Abstract:本试验旨在研究育成后期(10~17周龄)饲粮代谢能和蛋白质水平对大午粉1号商品代蛋鸡生长性能、器官指数、小肠发育以及产蛋高峰期生产性能和蛋品质的影响;通过建立饲粮代谢能和蛋白质水平与所检测指标之间的回归模型,得到育成后期大午粉1号商品代蛋鸡饲粮中适宜的代谢能和蛋白质水平。本研究共包括2个试验。试验1:随机选取810只64日龄蛋鸡,将其随机分为9组,每组6个重复,每个重复15只。采用3[代谢能水平:11.77(高)、11.27(中)、10.77 MJ/kg(低)]×3[蛋白质水平:16.50%(高)、15.50%(中)、14.50%(低)]试验设计,共配制9种试验饲粮,分别饲喂上述9组试验鸡,试验期8周(10~17周龄)。试验2:试验鸡的分组情况保持不变,所有试验鸡饲喂同一饲粮(代谢能水平:10.91 MJ/kg;蛋白质水平:15.98%),试验期14周(18~31周龄)。试验1结果显示:1)饲粮代谢能水平对蛋鸡平均日采食量(ADFI)、料重比(F/G)和胫骨长有显著影响(P<0.05);饲粮蛋白质水平对蛋鸡ADFI和胫骨长有显著影响(P<0.05);饲粮代谢能和蛋白质水平的互作效应对蛋鸡ADFI、平均日增重(ADG)和F/G均有显著影响(P<0.05)。2)饲粮代谢能和蛋白质水平及二者的互作效应对蛋鸡各器官指数均无显著影响(P>0.05)。3)饲粮代谢能水平对蛋鸡空肠、十二指肠、小肠长度有显著影响(P<0.05);饲粮代谢能和蛋白质水平的互作效应对蛋鸡空肠和小肠长度有显著影响(P<0.05)。试验2结果显示:1)育成后期饲粮代谢能和蛋白质水平对蛋鸡产蛋高峰期生产性能均没有显著影响(P>0.05),随着育成后期饲粮代谢能水平的升高,蛋鸡产蛋高峰期ADFI呈下降趋势;育成后期饲粮代谢能和蛋白质水平的互作效应对蛋鸡产蛋高峰期ADFI、平均日产蛋量、料蛋比(F/E)有显著影响(P<0.05)。2)育成后期蛋鸡饲粮代谢能水平对蛋鸡产蛋高峰期蛋黄颜色和蛋形指数有显著影响(P<0.05);育成后期蛋鸡饲粮蛋白质水平对蛋鸡产蛋高峰期蛋黄颜色有显著影响(P<0.05);育成后期饲粮代谢能和蛋白质水平的互作效应对蛋鸡产蛋高峰期蛋壳厚度和蛋形指数有显著影响(P<0.05)。通过对育成后期ADFI、F/G以及空肠、十二指肠、小肠长度和蛋黄颜色进行二次曲线拟合,得出大午粉1号商品代蛋鸡育成后期饲粮中适宜代谢能水平分别为10.902、10.720、11.404、11.446、11.374和11.760 MJ/kg;通过对育成后期胫骨长进行二次曲线拟合,得出大午粉1号商品代蛋鸡育成后期饲粮中适宜蛋白质水平为15.300%。综合上述指标,推荐育成后期(10~17周龄)大午粉1号商品代蛋鸡饲粮中代谢能水平为10.720~11.760 MJ/kg,蛋白质水平为15.300%。

  • 5~9周龄大午粉1号商品代蛋雏鸡对饲粮能量和蛋白质的需要量研究

    Subjects: Biology >> Zoology submitted time 2018-12-24 Cooperative journals: 《动物营养学报》

    Abstract:本试验通过建立饲粮能量或蛋白质水平与生长性能、血清生化指标、器官指数等指标的回归模型,旨在确定5~9周龄大午粉1号商品代蛋雏鸡对饲粮能量和蛋白质的需要量。选取810只遗传背景相同、体重接近、健康状态良好的28日龄大午粉1号商品代蛋雏鸡,随机分为9组,每组6个重复,每个重复15只蛋雏鸡。采用3×3双因素试验设计,设定饲粮中能量水平分别为12.42、11.92和11.42 MJ/kg,蛋白质水平分别为18.75%、17.75%和16.75%,共配制9种试验饲粮。试验期为35 d。结果显示:1)随着饲粮能量水平的升高,蛋雏鸡9周龄时胫长、胸宽、龙骨长、血清甘油三酯含量呈上升的趋势,5~9周龄平均日增重呈先下降后上升的趋势。2)随着饲粮蛋白质水平的升高,蛋雏鸡9周龄时体重(终末体重)、胸宽以及5~9周龄平均日增重呈先升高后降低的趋势。3)饲粮能量水平与蛋白质水平的互作效应对9周龄大午粉1号商品代蛋雏鸡的胸宽、龙骨长、血清甘油三酯含量有显著影响(P<0.05)。4)通过对蛋雏鸡胸宽、龙骨长、血清甘油三酯含量与饲粮能量水平进行二次曲线拟合,得出饲粮适宜能量水平分别为11.420、11.483、11.379 MJ/kg,平均值为11.427 MJ/kg;通过对9周龄时体重与饲粮蛋白质水平二次曲线拟合,得到饲粮适宜蛋白质水平为17.902%。综合蛋雏鸡体尺指标、生长性能、器官指数和血清生化指标得出,5~9周龄大午粉1号商品代蛋雏鸡的能量和蛋白质需要量分别为11.427 MJ/kg、17.902%。

  • 高、低钙饲粮交替饲喂对蛋鸡产蛋后期生产性能、蛋品质及血清指标的影响

    Subjects: Biology >> Zoology submitted time 2018-12-24 Cooperative journals: 《动物营养学报》

    Abstract:本试验旨在研究高、低钙饲粮交替饲喂对蛋鸡产蛋后期生产性能、蛋品质及血清指标的影响。试验选取68周龄的大午粉1号蛋种鸡64只,随机分为2组,每组32只,单笼饲养于个体智能鸡笼内,对照组08:00和14:00分别饲喂43.3、86.7 g中钙饲粮(钙含量为3.66%),试验组08:00饲喂43.3 g低钙饲粮(钙含量为2.00%),14:00饲喂86.7 g高钙饲粮(钙含量为4.49%)。试验期为5周,其中预试期1周,正试期为4周。结果显示:试验组各周的平均日采食量、平均蛋重、产蛋率、料蛋比与对照组无显著差异(P>0.05),但试验组各周的产蛋率在数值上高于对照组。试验组第2周的蛋壳厚度显著高于对照组(P<0.05),而试验组各周蛋白高度、哈氏单位与对照组无显著差异(P>0.05)。对照组中,18:00和22:00的血清钙含量显著高于10:00和14:00(P<0.05),高于06:00和次日02:00(P>0.05);试验组中,22:00的血清钙含量极显著高于06:00、10:00、18:00和次日02:00(P<0.01),并显著高于14:00和18:00(P<0.05);从06:00到22:00,试验组血清钙含量一直呈现增长的趋势,在22:00时,试验组血清钙、降钙素含量均显著高于对照组(P<0.05)。由此得出,高、低钙饲粮交替饲喂(将高钙饲粮在下午饲喂)可提高蛋鸡产蛋后期的产蛋率和对钙的吸收和沉积,并且可在一定程度上改善蛋壳质量。

  • 高、低钙饲粮交替饲喂对蛋鸡产蛋后期生产性能、蛋品质及血清指标的影响

    Subjects: Biology >> Zoology submitted time 2018-12-24 Cooperative journals: 《动物营养学报》

    Abstract:本试验旨在研究高、低钙饲粮交替饲喂对蛋鸡产蛋后期生产性能、蛋品质及血清指标的影响。试验选取68周龄的大午粉1号蛋种鸡64只,随机分为2组,每组32只,单笼饲养于个体智能鸡笼内,对照组08:00和14:00分别饲喂43.3、86.7 g中钙饲粮(钙含量为3.66%),试验组08:00饲喂43.3 g低钙饲粮(钙含量为2.00%),14:00饲喂86.7 g高钙饲粮(钙含量为4.49%)。试验期为5周,其中预试期1周,正试期为4周。结果显示:试验组各周的平均日采食量、平均蛋重、产蛋率、料蛋比与对照组无显著差异(P>0.05),但试验组各周的产蛋率在数值上高于对照组。试验组第2周的蛋壳厚度显著高于对照组(P<0.05),而试验组各周蛋白高度、哈氏单位与对照组无显著差异(P>0.05)。对照组中,18:00和22:00的血清钙含量显著高于10:00和14:00(P<0.05),高于06:00和次日02:00(P>0.05);试验组中,22:00的血清钙含量极显著高于06:00、10:00、18:00和次日02:00(P<0.01),并显著高于14:00和18:00(P<0.05);从06:00到22:00,试验组血清钙含量一直呈现增长的趋势,在22:00时,试验组血清钙、降钙素含量均显著高于对照组(P<0.05)。由此得出,高、低钙饲粮交替饲喂(将高钙饲粮在下午饲喂)可提高蛋鸡产蛋后期的产蛋率和对钙的吸收和沉积,并且可在一定程度上改善蛋壳质量。

  • 多种油脂肪乳在胃肠外科重症患者术后肠外营养中的应用

    Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2017-12-07 Cooperative journals: 《南方医科大学学报》

    Abstract: Objective To investigate the effect of parenteral nutrition support with a lipid emulsion formulation (containing soybean oil, medium chain triglycerides, olive oil, and fish oil [SMOF]) in intensive care patients following major gastrointestinal surgeries. Methods According to a randomized, prospective and case-controlled design, 72 intensive care patients following major gastrointestinal surgeries between January and December, 2014 were randomized equally into SMOF group and control group to receive parenteral nutrition support with SMOF and medium or long chain lipid emulsion, respectively. Before and at 4 and 9 days after commencement of parenteral nutrition support, the patients were examined for alanine aminotransferase (ALT), total bilirubin (TBIL), albumin (propagated), C-reactive protein (CRP), interleukin 6 (IL-6), and endotoxin levels. The patients' average length of stay in intensive care unit (ICU), the days of using antibiotics, and the incidence rate of postoperative complication were recorded. Results On day 4 postoperatively, the levels of CRP and IL-6 were significantly lower in SMOF group than in the control group (t=2.669 and 2.676, respectively; P<0.05), and on day 9, the patients in SMOF group showed significantly lower levels of ALT, TBIL, CRP and IL-6 (t=2.487, 3.497, 3.762, 2.180, respectively; P<0.05) than the control group, but ALB and endotoxin levels remained comparable between the two groups. The average length of stay in ICU and the days of using antibiotics were significantly shorter in SMOF group than in the control group (t= 2.94 and 2.17, respectively; P<0.05); SMOF group showed a lower incidence of postoperative infections than the control group, but the difference was not statistically significant (χ2 =1.047, P>0.05). Conclusion For intensive care patients following major gastrointestinal surgeries, postoperative parenteral nutrition support with SMOF can effectively reduce the release of inflammatory mediators, protect important visceral functions, reduce postoperative complications, shorten the length of ICU stay, and improve the prognosis of the patients.

  • CeO2对超音速火焰喷涂WC-12Co涂层腐蚀行为影响研究

    Subjects: Materials Science >> Materials Science (General) submitted time 2016-11-15 Cooperative journals: 《金属学报》

    Abstract:采用超音速火焰喷涂在Q345基体上制备了微米WC-12Co、纳米改性WC-12Co和CeO2改性WC-12Co涂层,利用扫描电镜、X射线衍射仪、显微硬度计和共聚焦显微镜分析涂层的微观组织,通过极化试验和浸泡腐蚀试验等试验方法研究涂层在1mol/L H2SO4溶液中的腐蚀行为。结果表明:纳米CeO2的加入可以显著降低涂层的孔隙率,能有效的减少点蚀的发生;添加纳米CeO2可以使涂层电极电位发生正移,降低腐蚀电流密度,生成稳定的钝化膜,降低涂层的维钝电流密度,提高涂层的耐腐蚀性能;纳米CeO2改性WC-12Co涂层的腐蚀机制为由孔隙诱发的点蚀,其他区域并没有被腐蚀,而微米WC-12Co涂层和纳米改性WC-12Co涂层不仅Co粘结相被全面腐蚀,而且在孔隙处也发生了严重的点蚀。