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1.
Hypertension is common in the conventional hemodialysis population. While hypertension in the general population has been shown to reduce survival, the issue is less clear in the dialysis population. This review focuses on recent studies showing a favorable outcome in hypertensive hemodialysis patients compared to those with lower blood pressure. Possible explanations for this paradoxical relationship are examined and practical suggestions given for the management of hypertension in the hemodialysis patient.  相似文献   

2.
FRP作为一种新型人工复合材料,因其强度高、密度小、施工简便、耐腐蚀性高、不增加构件截面尺寸等优点,被广泛应用于土木工程结构加固中.FRP约束混凝土本构关系、极限抗压强度、极限应变等力学参数是进行结构强度补强和延性加固的前提和基础.为使FRP约束混凝土更好地应用于工程实践,基于有限元分析手段和国内外近10年来关于FRP约束混凝土的试验研究与分析成果,深入分析和研究了约束比、混凝土柱截面形状、尺寸、强度、FRP用量、模量、FRP强度以及延伸率对FRP约束混凝土力学性能的影响.  相似文献   

3.
条形码在包装上使用影响因素分析   总被引:5,自引:4,他引:1  
黄晓英 《包装工程》2003,24(2):59-60,80
条形码技术是数据自动识别十分有效的方法,条形码的使用效果与条形码制选择、包装位置和识读器类型等因素有密切关系,在此分析了影响条形码在包装上使用的因素以及采取相应的措施。  相似文献   

4.
文章从原材料和工艺条件等方面探讨了影响膨化硝铵炸药性能的几个因素,由此得出了膨化硝铵炸药的较佳工艺条件.  相似文献   

5.
沈丽燕  钱军浩 《包装工程》2012,33(17):126-129,140
结合喷墨印刷原理分析了影响RFID标签识别性能的因素,进而研究了叠印率及底基温度对RFID标签天线识别性能的影响。实验证明:随着叠印率的增大,导体的连续性增强,墨层增厚,线宽变大,标签识别性能也得以提高,而且提高操作温度对导体连续性起着正作用,表面更为光滑,线宽先增大后减小。  相似文献   

6.
廖佳庆  杨长辉  黄洪胜 《材料导报》2007,21(Z2):501-503
研究了配制参数碱组分种类和掺量、矿渣细度、溶矿比、矿渣/集料比和砂率等对碱矿渣混凝土强度的影响.研究表明,其它条件相同时,碱矿渣混凝土强度随矿渣细度增加而提高;随溶矿比的增大而降低;随矿组分用量增加而提高;矿渣/集料比和砂率对碱矿渣混凝土强度影响较小;模数在1.0~2.0范围内,碱矿渣混凝土的强度随水玻璃模数提高呈增长趋势.  相似文献   

7.
题正义  路秀伟 《爆破》2009,26(3):92-93,107
毫秒雷管延期元件的秒量精度影响因素很多,包括延期药质量、延期元件加工工艺、延期元件贮存等.通过对延期元件加工工艺中的不同拉拔结构、不同药芯直径和延期元件切长对毫秒雷管秒量影响的实验研究,找出提高延期元件秒量精度的工艺技术途径,为更好地生产该产品奠定基础.  相似文献   

8.
We report an instability of 4He crystal surface during a large modification of its shape observed by schlieren photography. 4He crystal was nucleated on an ultrasound transducer which was placed in the upper part of the sample cell facing the bottom. The crystal was grown on the transducer and the lowest part of it eventually touched the bottom of the cell. Almost immediately, the crystal started to change shape very quickly to adjust itself to the new boundary condition. During this large deformation, the hexagonal shape of the crystal surrounded by facets became unstable and the surface became corrugated. The corrugation pattern during the deformation was observed by a high-speed camera. The results were compared with Kelvin-Helmholtz type instability which Uwaha and Nozières predicted.   相似文献   

9.
The flow behaviour of 2024 aluminium during drop weight compression tests was investigated. Use of cylindrical specimens of different height to diameter ratios, of different orientations and having undergone varying levels of prestrain, enabled the development of shear bands occuring within these specimens to be studied. The shear surfaces display a conical geometry and appear to develop in the presence of thermal softening after a flow stress maximum has been reached. Fracture along these surfaces appears to be associated with the rotation of strings of inclusions into the plane of the surface as well as severe deformation along the bands which leads to both thermal softening and exhaustion of matrix material ductility.  相似文献   

10.
Background and Purpose:  Colloid osmotic pressure (COP) in plasma rises by ultrafiltration during hemodialysis, and it consequently causes plasma refilling in which water moves from interstitial tissue to capillary space. Although hemodynamic stability is one of the important factors for good dialysis outcome, no informative and convenient indicators are available other than monitoring of blood pressure. Thus, we measured COP during hemodialysis whether COP can be used as an indicator for the hemodynamic status in comparison with hematocrit (Ht). Plasma osmolality, ultrafiltration volume, and the alteration of blood pressure were also measured to examine whether COP is associated with them.
Method:  Sixteen patients hospitalized in this hospital were examined. Amongst them, 10 patients underwent both dialysis and ultrafiltration, while 4 patients received only dialysis and 2 patients were with ultrafiltration only by extracorporeal ultrafiltration method. Ultrafiltration was performed with constant speed to the dry weight for 4 h. The measurements of COP, plasma osmolality, Ht levels, and blood pressure were performed at 30 min (12.5% of the total water removal), 1 h (25%), 2 h (50%), and 3 h (75%) after the start of hemodialysis and also at the end of dialysis (100%).
Result:  COP markedly rose by 26.0% (±13.3%) in the patients who received both dialysis and ultrafiltration, whereas Ht rose by only 13.6% (±5.21%). And the curve for COP increase was sigmoid shape, whereas that for Ht showed linear change. On the other hand, in the patients whose Ht levels showed low values, the curves for both COP and Ht showed similar pattern.
Conclusion:  These results suggest that COP is a more sensitive indicator to be monitored for the hemodynamic status than Ht during hemodialysis.  相似文献   

11.
制造企业库存长鞭效应影响因子分析及控制方法   总被引:1,自引:0,他引:1  
长鞭效应是供应链管理中由于供应链合作伙伴之间缺乏合作与协调的结果。从理论上刻画了长鞭效应的内在本质,分析了产生长鞭效应的原因,以一个跨国公司的库存管理为例,详细分析了影响长鞭效应三个方面的因子:(1)集中式与分散式管理;(2)需求与供应特征;(3)产品类型与库存再订货点。还从供需合作关系的角度提出了改善长鞭效应的几个控制方法。  相似文献   

12.
刘洋 《制冷》2007,26(2):7-10
以天津产结球白菜作为实验对象,探讨复压阶段的温度回升,以及在真空室内不同摆放形式和不同包装方式对蔬菜最终温度分布的影响,对比分析试验数据,为今后真空预冷技术的推广应用提供参考.  相似文献   

13.
李喆  史佳卉 《包装工程》2024,(8):242-253
目的 研究双碳背景下时尚品牌品牌价值的影响因素,研究重点聚焦在低碳营销、低碳品牌形象与消费者购买意愿之间的关系。方法 首先,梳理出双碳背景下时尚品牌纺织服装产品碳足迹在原材料采购、生产制造和产品销售三个环节所面临的挑战,并分析其成因;其次,根据成因与品牌低碳营销、低碳品牌形象和消费者购买意愿的关系,构建了双碳背景下时尚品牌价值影响因素模型,提出研究假设;最后,运用因子分析、相关性分析和回归分析来验证变量之间的关系,并测试中介效应。结果 品牌低碳营销对低碳品牌形象产生正向影响,同时品牌低碳营销和低碳品牌形象均对品牌价值产生正向影响。消费者购买意愿在品牌低碳营销和低碳品牌形象影响品牌价值中起到部分中介作用。结论 影响时尚品牌价值的主要因素包括品牌的低碳营销策略和低碳品牌形象建设。为实现可持续发展目标,时尚品牌需要在原材料采购、生产制造和产品销售等环节采取低碳措施,积极推行低碳营销策略,塑造具有低碳特色的品牌形象,从而提高品牌价值。本研究对象是时尚品牌中的纺织服装产品,但研究结果也可以在一定程度上适用于奢侈品牌、生活方式品牌及其领域产品。  相似文献   

14.
Background:  Cardiovascular complications due to atherosclerosis (AS) are the major cause of mortality in hemodialysis (HD) patients. Inflammation may play an important role in the development of AS. Several studies have demonstrated the association of acute-phase proteins and cytokines with AS in the general population and in HD patients. Interleukin-10 (IL-10) is an anti-inflammatory cytokine. The aim of study was to compare serum levels inflammatory and anti-inflammatory indicators in HD patients according to the presence or absence of AS.
Methods:  Thirty-three HD patients were enrolled. AS was defined as the detection of plaques by Doppler ultrasonography. The patients were subgrouped according to the presence or absence of plaques. Serum levels of IL-1, IL-2, IL-6, IL-10, C-reactive protein (CRP) and tumor necrosis factor-α (TNF-α) were measured. The factors for AS such as age, gender, hypertension, hyperlipidemia, and HD duration were also evaluated.
Results:  We found that the patients with AS had significantly higher hs-CRP and lower IL-10. Blood pressure values were also increased in patients with AS. Additionally, there was an increased correlation between CRP and IL-10.
Conclusions:  AS(+) patients undergoing HD had low serum levels of anti-inflammatory cytokine IL-10 and high serum levels of hs-CRP. These results may suggest that the limitation of anti-inflammatory response in atherosclerotic uremic patients is a triggering or contributing factor for AS.  相似文献   

15.
Failure in nitrogen removal of cokes wastewater occurs occasionally during summer season (38 degrees C) due to the instability of nitrification process. The objective of this study was to examine why the nitrification process is unstable especially in summer. Various parameters such as pH, temperature, nutrients and pollutants were examined in batch experiments using activated sludge and wastewater obtained from a full-scale cokes wastewater treatment facility. Batch experiments showed that nitrification rate of the activated sludge was faster in summer (38 degrees C) than in spring or autumn (29 degrees C) and the toxic effects of cyanide, phenol and thiocyanate on nitrification were reduced with increasing temperature. Meanwhile, experiment using continuous reactor showed that the reduction rate in nitrification efficiency was higher at 38 degrees C than at 29 degrees C. In conclusion, the instability of full-scale nitrification process in summer might be mainly due to washing out of nitrifiers by fast growth of competitive microorganisms at higher temperature under increased concentrations of phenol and thiocyanate.  相似文献   

16.
Introduction: In 2001 our Renal Dialysis Unit underwent a major renovation to five stations. The new space and funding allowed for acquisition of new state‐of‐the‐art hemodialysis machines. We describe our experience with the Gambro Phoenix with Diascan and Exalis. Prior to the move an evaluation was undertaken. Criteria for selection with a scoring tool were utilized to rate machine performance for use in children. The decision for the Gambro Phoenix machine was based on: the performance rated highly due to ease of set up; large viewing touch screen; compatibility with existing equipment; benefits of online clearance monitoring (Diascan); network data management system (Exalis) and the future availability of blood volume monitoring (Hemoscan). Our program was the first center to dialyze a pediatric patient on the Phoenix machine in Canada. Patients and results: 13 patients (age 2–23 years) were hemodialyzed between May 2002 and September 2003 for periods of 2 week to 16 months, greater than 5000 h of dialysis time. The move was not uneventful. During the first months of operation issues such as inadequate electrical supply for the new machines, reverse osmosis (RO) pump failure, leaks, and no emergency power to the RO were prevalent. The new software also exposed glitches. Subsequent Phoenix use proceeded uneventfully. Staff were able to problem solve easily with clinical and technical support from Gambro Canada. Education for the online clearance monitoring, Diascan and Exalis, was necessary. No major problems with dialysis were encountered. The benefits and reliability of Diascan have been previously described (Lindsay RM, Sternby J, Semin Dial. 2001; 14:300). Diascan readings provided real‐time measurement of sodium (Na), which correlated well with laboratory values. Automatic readouts of Kt/V allowed for monitoring of dialysis adequacy which was consistent with calculated percent reduction in urea (PRU). At this point, use of the Phoenix has been demonstrated to work well in a pediatric facility.  相似文献   

17.
18.
The properties of the neutral helium (hydrogen) film under antigravitational conditions are described. The existence of the critical liquid film thickkness d* is predicted. Some details of the liquid film profile reconstruction are discussed.  相似文献   

19.
功能梯度材料制备过程影响因素的数值研究   总被引:4,自引:0,他引:4  
本文用数值计算的方法对重力浇铸下Al—Si/SiC颗粒系统(合金基质的功能梯度材料)凝固过程进行了研究,分析了凝固条件及各种不同参数对铸件中颗粒和溶质浓度分布的影响。结果表明,凝固件中颗粒体积分数分布都大致可分为三个区域:靠近底部的颗粒堆积区,靠近顶部的颗粒体积分数减小或近似为零区,及中部附近颗粒体积分数近似保持不变区。浇铸的初始温度,颗粒初始体积分数,颗粒直径和冷却速率等参数对颗粒和溶质浓度分布有很大影响。  相似文献   

20.
X80管线钢焊接粗晶区韧化因素的研究   总被引:1,自引:0,他引:1  
采用热模拟技术研究了不同热循环对X80管线钢焊接粗晶区低温冲击韧度的影响.实验结果表明,随着冷却时间t8/5的增加,第二相粒子的数量减少且出现聚集现象,晶粒尺寸增加,但是当t8/5小于6.8s时,粒状贝氏体含量较高,板条束贝氏体细小且方向性较弱,试样的冲击韧性较高;而当t8/5超过6.8s后,粒状贝氏体含量逐渐下降,板条贝氏体逐渐粗大、平行,试样韧性又逐渐降低.M-A组元由于其含量低,尺寸小,对韧性的影响不显著.因此为提高焊接粗晶区的韧性,应采用小线能量和合适的预热温度来控制晶粒尺寸和组织形态.  相似文献   

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