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THE INFLUENCE OF H_2O ON THE IMPEDANCE SPECTRA OF Na-beta ALUMINA TUBES
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作者 杨华铨 夏恒霞 +1 位作者 张倩文 杨文治 《Chinese Science Bulletin》 SCIE EI CAS 1985年第5期620-624,共5页
The conductivity and stability of Na-beta alumina are markedly affected by H2O. This is a problem of both theoretical and practical interest and has been studied recently by various authors (see e.g. Refs. [1—3] and... The conductivity and stability of Na-beta alumina are markedly affected by H2O. This is a problem of both theoretical and practical interest and has been studied recently by various authors (see e.g. Refs. [1—3] and the works cited therein). As for the influence of H2O on the conductivity of Na-beta almina (hereafter referred to as beta alumina except in case special reference to Na-ion is necessary), it was usually measured with mono-or poly-crystalline beta alumina in plate form with few authors using directly beta alumina tubes in contact with moist air. In a previous paper we 展开更多
关键词 hereafter ALUMINA CITED CRYSTALLINE therein referred markedly moist outer DILUTE
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CHANGES OF PLASMA BETA-ENDORPHIN LEVELS BEFORE AND AFTER PERCUTANEOUS TRANSVENOUS MITRAL COMMISSUROTOMY IN PATIENTS WITH MITRAL STENOSIS
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作者 尹瑞兴 朱树雄 +3 位作者 赵定菁 陶新智 曾知恒 夏树楹 《Chinese Medical Journal》 SCIE CAS CSCD 1995年第11期14-21,共8页
To clarify the contribution of left atrial pressure to the secretion of beta-endorphin, we have investigated the relation between plasma beta endorphin levels and hemodynamic changes in 35 patients with mitral stenosi... To clarify the contribution of left atrial pressure to the secretion of beta-endorphin, we have investigated the relation between plasma beta endorphin levels and hemodynamic changes in 35 patients with mitral stenosis undergoing percutaneous transvenous mitral commissurotomy (PTMC). Before PTMC, plasma beta-endorphin levels obtained from the antecubital vein (28.91 ± 5.59 pg / ml) and from the femoral vein (28.20 ± 5.44 pg / ml) in the patients with mitral stenosis were significantly higher than those obtained from the antecubital vein in the healthy volunteers (22.59 ± 3.86 pg / ml, n = 34, P< 0.001 for each). The levels of beta-endorphin in the femoral vein correlated well with the mean left atrial pressure (r=0.777, P< 0.001) and the mean right atrial pressure (r = 0.450, P<0.01) before the procedure. The antecubital venous levels of beta-endorphin in patients in New York Heart Association functional Classess Ⅱ (26.45 ± 5.39 pg / ml, n = 20) and Ⅲ (32.20 ± 4.02 pg / ml, n = 15) were significantly higher than those in control subjects (P< 0.005 and P< 0.001, respectively). The differences between Classes Ⅱ and Ⅲ were significant (P < 0.001). The plasma levels of beta-endorphin in the patients complicated with atrial fibrillation were also significantly higher than those in patients with normal sinus rhythm (33.31 ± 3.22 pg / ml, n= 13 vs 26.32± 5.07 pg / ml, n = 22, P< 0.001). In ten to fifteen minutes after commissurotomy, plasma levels of beta-endorphin in the femoral vein significantly increased from 28.20 ± 5.44 to 33.14 ± 5.72 pg / ml (P< 0.001). In seventy-two hours after the procedure, plasma beta-endorphin levels in the antecubital vein fell to 24.37 ± 2.59 pg / ml (P< 0.001 vs before PTMC and P<0.05 vs control subjects). Plasma beta-endorphin levels in the patients with atrial fibrillation (26.62 ± 2.36 pg / ml, P< 0.001 vs before PTMC and P< 0.002 vs control subjects) were still higher (P< 0.001) than those in patients with normal shins rhythm (23.05 ± 1.65 pg / ml, P< 0.001 vs before PTMC and P>50 vs control subjects. There was a significant correlation between the levels of beta-endorphin in the antecubital vein and heart rate (r = 0.502, P< 0.001), mean transmitral pressure gradient (r = 0.543, P< 0.001) or mitral valve area (r = -0.710, P< 0.001) before and 72 hours after the procedure. 展开更多
关键词 PTMC In CHANGES OF PLASMA BETA-ENDORPHIN LEVELS BEFORE AND AFTER PERCUTANEOUS TRANSVENOUS MITRAL COMMISSUROTOMY IN PATIENTS WITH MITRAL STENOSIS
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Navigating the integration of artificial intelligence in Nursing:Opportunities,challenges,and strategic actions 被引量:2
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作者 Rick Yiu Cho Kwan Anson Chui Yan Tang +8 位作者 Janet Yuen Ha Wong Wentao Zhou Maria Theresa Belcina Gracielle Ruth Adajar Misae Ito Irvin Ong Younhee Kang Jing Jing Su Julia Sze Wing Wong 《International Journal of Nursing Sciences》 2025年第3期241-245,共5页
The advent of artificial intelligence(AI)in recent years has brought about transformative changes across various sectors,including healthcare.In nursing practice,education,and research,AI has the potential to revoluti... The advent of artificial intelligence(AI)in recent years has brought about transformative changes across various sectors,including healthcare.In nursing practice,education,and research,AI has the potential to revolutionize traditional methodologies,enhance learning experiences,and improve patient outcomes.Integrating AI tools and techniques can provide clinicians with smarter clinical solutions and nursing students with more robust and interactive learning environments,while also advancing research capabilities in the field.Despite the promising prospects,the incorporation of AI into nursing practice,education,and research presents several challenges.Firstly,there is a concern about the potential displacement of human roles in nursing due to automation,which may affect the human-centric nature of nursing care.Secondly,there are issues related to the lag in AI competency among nurses.Many current nursing curricula do not include comprehensive AI training,leading to a lack of preparedness in utilizing these technologies effectively.Lastly,the ethical implications of AI in healthcare,such as data privacy,patient consent,and the potential for biased algorithms,need to be meticulously addressed.To harness the full potential of AI in nursing practice,education,and research,several strategic actions including reinvesting in humanistic practice,revising core competencies and curriculum,and developing new ethical guidelines. 展开更多
关键词 Artificial intelligence Challenge COMPETENCY ETHICS Education NURSING
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基于鼠李糖脂为乳化剂的菊苣提取物自微乳口含片的制备及质量评价
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作者 杨楠楠 杨乐 张卉 《沈阳化工大学学报》 2025年第1期64-71,共8页
为探究鼠李糖脂作为乳化剂在菊苣提取物自微乳(CE-SMEDDS)口含片制备中应用的可行性,采用响应面试验(Box-Behnken)优化了口含片的配方,通过片重差异、片剂硬度、脆碎度和含化时间等指标对所制得的自微乳口含片质量进行了评价,并通过滤... 为探究鼠李糖脂作为乳化剂在菊苣提取物自微乳(CE-SMEDDS)口含片制备中应用的可行性,采用响应面试验(Box-Behnken)优化了口含片的配方,通过片重差异、片剂硬度、脆碎度和含化时间等指标对所制得的自微乳口含片质量进行了评价,并通过滤纸片法测定了其抑菌性能.结果表明:CE-SMEDDS口含片的最佳配方为固体吸附混合物Ma[m(CE-SMEDDS)∶m(微晶纤维素)=1∶1]质量分数为38.45%,羟丙甲基纤维素(HPMC-E5)质量分数为6.50%,木糖醇质量分数为44.75%,姜黄素质量分数为0.01%,玉米淀粉质量分数为10.29%;菊苣提取物自微乳口含片的片重差异、片剂硬度、脆碎度和含化时间等均符合《中国药典》片剂质量标准.经小杯法溶出度试验检测,CE-SMEDDS制剂与口含片中的菊苣提取物分别在30和50 min达到了90%的累计释放率,表明口含片的缓释效果较自微乳的更好.经滤纸片法抑菌试验检验,口含片对大肠杆菌和金黄色葡萄球菌均表现出良好的抑菌效果. 展开更多
关键词 鼠李糖脂 自微乳 口含片 菊苣提取物 抑菌活性
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基于胸部模体不同扫描体位下胸部CT图像质量与辐射剂量的影响研究
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作者 隋岩 陶士华 +5 位作者 刘康 盖兴慧 高志远 陈钊睿 龚浩 杨德武 《中国医学装备》 2025年第9期17-20,共4页
目的:基于胸部模体不同扫描体位下行胸部CT扫描,探讨其对图像质量与辐射剂量的影响。方法:在拟人胸部模体乳腺区域放置热释光剂量计(TLD),应用CT对胸部模体进行常规仰卧位(仰卧组)和俯卧位(俯卧组)的扫描,调节不同噪声指数(NI=10~23)控... 目的:基于胸部模体不同扫描体位下行胸部CT扫描,探讨其对图像质量与辐射剂量的影响。方法:在拟人胸部模体乳腺区域放置热释光剂量计(TLD),应用CT对胸部模体进行常规仰卧位(仰卧组)和俯卧位(俯卧组)的扫描,调节不同噪声指数(NI=10~23)控制辐射剂量,其他扫描参数固定,每组采集12个序列图像。记录不同扫描体位下,感兴趣区域(ROI)的CT均值(AV)、标准差(SD)计算图像信噪比(SNR)、对比度噪声比(CNR)。通过TLD测量乳腺区域辐射剂量,记录容积CT剂量指数(CTDI_(vol))和剂量-长度乘积(DLP)。结果:不同扫描体位下,俯卧组乳腺器官辐射剂量(8.33±3.61)mGy低于仰卧组(9.79±4.49)mGy;两组比较差异有统计学意义(t=6.57,P<0.05),两组CTDI_(vol)、DLP比较差异无统计学意义(P>0.05);两组图像肺组织的CT值、SD、SNR及CNR与乳腺组织的CT值比较差异均无统计学意义(P>0.05),俯卧组乳腺组织的SD、SNR、CNR均低于仰卧组,差异有统计学意义(t=-13.33、-10.59、6.70,P<0.05)。两组图像主观评价的肺内组织边缘清晰度、乳腺软组织层次、噪声及骨组织产生伪影的主观评分比较,差异均无统计学意义(P>0.05)。结论:胸部低剂量CT用于临床体检时,CT扫描采取俯卧位可获得满足肺部诊断的图像质量,降低乳腺的辐射剂量,符合辐射防护最优化的技术原则。 展开更多
关键词 胸部CT 扫描体位 辐射剂量 图像质量
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各型HBV感染者血清和肝细胞β2微球蛋白的意义 被引量:3
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作者 刘建平 彭文伟 +1 位作者 李梦东 李奇芬 《世界华人消化杂志》 CAS 1998年第S2期195-197,共3页
目的动态观察各型HBV感染者血清β2微球蛋白(β2MG)水平及肝内表达,研究其临床意义方法HBV感染者128例中,无症状携带着(ASC)12例,急性肝炎(AH)26例,慢性肝炎(CH)56例,重型肝炎(SH)18例,肝硬变(LC)和原发性肝癌(HCC)... 目的动态观察各型HBV感染者血清β2微球蛋白(β2MG)水平及肝内表达,研究其临床意义方法HBV感染者128例中,无症状携带着(ASC)12例,急性肝炎(AH)26例,慢性肝炎(CH)56例,重型肝炎(SH)18例,肝硬变(LC)和原发性肝癌(HCC)各8例。设正常对照30例,用RIA和免疫级化法分别测定血清和肝内β2MG,与肝损害程度比较,分析临床意义结果除ASC外,各型乙肝和LC,HCC血清β2MG均有升高,其中,以SH,LC,CH和HCC为著;AH,SH肝细胞β2MG表达明显增强(正常肝细胞不表达),且其分布与肝组织炎症坏死区一致.血清β2MG水平和肝内表达强度与血清胆红素水平呈正相关.动态观察发现,AH于恢复期血清β2MG降至接近正常,SH死亡组β2MG水平明显高于存活组.结论β2MG参与HBV感染发病机制中肝组织免疫病理损害过程,动态观察血清β2MG水平可在一定程度上反映AH和SH的预后和转归。 展开更多
关键词 肝炎.病毒性 肝硬化 肝肿瘤 β2微球蛋白/分析
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应用β肾上腺素能受体阻滞剂规范治疗冠心病的中国专家共识 被引量:51
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作者 陈韵岱 +1 位作者 董蔚 汪京嘉 《中国循环杂志》 CSCD 北大核心 2020年第2期108-123,共16页
β肾上腺素能受体阻滞剂(β受体阻滞剂)已被证实可降低无禁忌证冠心病患者的全因死亡和心血管死亡风险,而我国冠心病人群中β受体阻滞剂的应用存在明显不规范,主要体现为使用率低、使用剂量不足和长期治疗依从性差。该共识在《β肾上腺... β肾上腺素能受体阻滞剂(β受体阻滞剂)已被证实可降低无禁忌证冠心病患者的全因死亡和心血管死亡风险,而我国冠心病人群中β受体阻滞剂的应用存在明显不规范,主要体现为使用率低、使用剂量不足和长期治疗依从性差。该共识在《β肾上腺素能受体阻滞剂在心血管疾病应用专家共识》基础上,汇总了近年来出现的新证据,进一步细化患者分类,明确了冠心病患者β受体阻滞剂应用应遵循的“BETA”原则,即Beneficial assessment(获益评估)、Enough dosage(足量应用)、Timely usage(及时使用)、Adequate titration(充分滴定),就不同患者人群使用β受体阻滞剂的临床指征、用法用量、治疗目标和疗程给出了明确建议。 展开更多
关键词 Β受体阻滞剂 冠心病 慢病 二级预防 专家共识
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一氧化氮阿司匹林对血小板聚集功能的影响 被引量:2
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作者 邢继军 Guo jian Xie +5 位作者 Don Zhang 丁列明 苏安英 柴锡庆 王印祥 王拥军 《中国动脉硬化杂志》 CAS CSCD 2005年第6期753-756,共4页
目的研究一种能缓慢释放一氧化氮的新型阿司匹林(BPI-1096)对血小板聚集功能的影响。方法正常人富血小板血浆与药物在37℃条件下温育10 min后,采用比浊法测定不同诱导剂作用下血小板聚集率。结果不同浓度条件下BPI-1096能够不同程度地... 目的研究一种能缓慢释放一氧化氮的新型阿司匹林(BPI-1096)对血小板聚集功能的影响。方法正常人富血小板血浆与药物在37℃条件下温育10 min后,采用比浊法测定不同诱导剂作用下血小板聚集率。结果不同浓度条件下BPI-1096能够不同程度地降低由二磷酸腺苷、血小板活化因子、肾上腺素及瑞斯托霉素诱导的血小板聚集(P<0.05),对花生四烯酸诱导的血小板聚集虽有降低但是无统计学意义;在相同浓度条件下BPI-1096与阿司匹林抑制血小板聚集率的作用无显著性差异;在不同浓度条件下BPI-1096对血小板聚集率不存在明显的浓度效应关系。结论BPI-1096作为一种新型的一氧化氮阿司匹林,能够显著抑制二磷酸腺苷、血小板活化因子、瑞斯托霉素及肾上腺素等多种诱导条件下体外血小板聚集功能,作用强度与传统阿司匹林疗效相当,其对血小板的抑制作用强度无明显的浓度效应关系。 展开更多
关键词 内科学 一氧化氮阿司匹林对血小板聚集功能的影响 比浊法 血小板聚集 一氧化氮阿司匹林 阿司匹林 诱导剂
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新兴市场国家跨国公司国际化动因、模式及理论模型:一个文献综述 被引量:6
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作者 张林刚 汪朗峰 Julien Pénin 《华东经济管理》 CSSCI 北大核心 2018年第5期157-164,共8页
新兴市场国家跨国公司以前所未有的速度和规模发展起来,理论界对这一现象的解释还处于发展阶段,远未达成共识。文章对已有相关文献进行综述,总结归纳了新兴市场国家跨国公司采取国际化战略的动因和模式。在此基础上,深入阐述了生命周期... 新兴市场国家跨国公司以前所未有的速度和规模发展起来,理论界对这一现象的解释还处于发展阶段,远未达成共识。文章对已有相关文献进行综述,总结归纳了新兴市场国家跨国公司采取国际化战略的动因和模式。在此基础上,深入阐述了生命周期理论、Uppsala模型、OLI模型和CSA/FSA模型等传统理论在解释新兴市场国家跨国公司国际化过程中的不足以及理论界对上述模型的扩展及创新。最后提出未来研究展望。 展开更多
关键词 新兴市场国家 跨国公司 国际化 模型扩展
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长板探测器数字X射线摄影术临床应用的可行性分析 被引量:1
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作者 王文海 贾绍田 +3 位作者 殷广宁 宋俊峰 张立新 赵英威 《中国医学装备》 2024年第3期24-28,共5页
目的:探讨长板探测器数字X射线摄影术(DR)应用于临床的可行性。方法:将长板探测器(简称探测器)直立竖放,金属铅线标记的刻度长尺立于探测器面板长轴中心前方20 cm处且与探测器中轴线平行。将3块空间分辨力测试方卡分别放置于探测器的上... 目的:探讨长板探测器数字X射线摄影术(DR)应用于临床的可行性。方法:将长板探测器(简称探测器)直立竖放,金属铅线标记的刻度长尺立于探测器面板长轴中心前方20 cm处且与探测器中轴线平行。将3块空间分辨力测试方卡分别放置于探测器的上、中、下3个位置,互相之间相隔30 cm呈45°方位贴敷于探测器面板上。源图像距离(SID)分别为100、150和200 cm时曝光,检测探测器上、中、下3个选点位置不同SID时获得的入射剂量;通过对方卡的图像观察确定3个位置点的空间分辨力;通过对金属铅线标记的刻度长度的投影测量与实际铅线长度之比,获得不同点位的放大率。观察探测器长轴方向有效焦点面的空间分布情况及其形态变化。结果:当SID为100、150和200 cm时,图像放大率随SID增大而减小,3种SID放大率比较,差异有统计学意义(F=223.80,P<0.001);不同SID对应的辐射剂量比较,差异有统计学意义(F=7.57,P<0.05);空间分辨力恒定为1.8 LP/mm。探测器短轴方向存在足跟效应,探测器长轴方向有效焦点呈上下对称显示。结论:长板探测器DR成像设备实现了一次曝光摄取脊柱全长或下肢全长的影像,可满足临床需求,提高X射线检查效率。 展开更多
关键词 长板探测器 数字X射线摄影术(DR) 影像放大失真 有效焦点 空间分布
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生物基涂料产品与生物基碳含量验证 被引量:3
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作者 南璇 张娅 蹇慧 《中国涂料》 CAS 2021年第5期52-57,共6页
通过对生物基及生物基涂料的基础阐述,表明生物基乳液内墙涂料目前是内墙涂料产品中的较高性能产品,不仅具有一定的生物基碳含量,还兼具有低VOC、低气味的健康环境友好性能,而且耐洗刷、遮盖力等物理性能优异,有的产品还兼具甲醛净化性... 通过对生物基及生物基涂料的基础阐述,表明生物基乳液内墙涂料目前是内墙涂料产品中的较高性能产品,不仅具有一定的生物基碳含量,还兼具有低VOC、低气味的健康环境友好性能,而且耐洗刷、遮盖力等物理性能优异,有的产品还兼具甲醛净化性能。中国生物基涂料产品不仅属于国内高端产品,其技术领先性在全球范围都有引领作用。扩大生物基涂料的使用范围将是应对减少化石能源的技术路径之一。 展开更多
关键词 生物基 生物基乳液内墙涂料 碳中和
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电渗析+MVR组合技术处理高盐度高氨氮废水工程实例 被引量:6
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作者 王明波 于凯 +1 位作者 刘国新 张军立 《煤炭与化工》 CAS 2020年第5期158-160,共3页
针对某制药企业生产过程中产生的高盐废水不能被下游的三废中心直接接收而需要进行处理的情况,采用电渗析+蒸汽再压缩技术(MVR)对高浓度的制药废水进行了蒸发浓缩,浓缩液经过结晶生产出的铵盐产品作为资源回收并再利用,从而实现了高盐... 针对某制药企业生产过程中产生的高盐废水不能被下游的三废中心直接接收而需要进行处理的情况,采用电渗析+蒸汽再压缩技术(MVR)对高浓度的制药废水进行了蒸发浓缩,浓缩液经过结晶生产出的铵盐产品作为资源回收并再利用,从而实现了高盐高氨氮废水的资源化应用。 展开更多
关键词 制药废水 电渗析 MVR 资源回收再利用
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制药行业低浓度无组织有机废气排放的达标治理实践研究 被引量:2
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作者 臧飞 牛洁平 张军立 《煤炭与化工》 CAS 2019年第6期155-157,160,共4页
制药行业在药物提取及化学合成过程中,要使用大量低沸点、易于挥发的有机溶剂。大部分溶剂浓度较高的有机挥发废气通过有组织管道进行收集,再通过冷凝、吸收、吸附、催化燃烧等方式进行达标处理。在生产过程中,还有一部分浓度较低的无... 制药行业在药物提取及化学合成过程中,要使用大量低沸点、易于挥发的有机溶剂。大部分溶剂浓度较高的有机挥发废气通过有组织管道进行收集,再通过冷凝、吸收、吸附、催化燃烧等方式进行达标处理。在生产过程中,还有一部分浓度较低的无组织逃逸气体,扩散较广,收集难度大,不利于大气污染防治和员工职业健康。通过对大气量、低浓度的有机废气(以甲苯为例)进行收集,通过分子筛转轮浓缩,再经冷凝、吸附处理的工程实践研究,总结出一条适合大气量、低浓度有机废气的处理路线。 展开更多
关键词 有机废气 低浓度有机废气 气体冷凝 气体吸附 分子筛
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高性能SiC纤维的进展 被引量:1
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作者 智欧 钱立军 《山东陶瓷》 CAS 2018年第6期10-21,共12页
本文详细介绍了商品SiC纤维的生产工艺,包括气相沉积(CVD)法以及聚合物先驱体法,并对这两种工艺特色进行了总结,同时也详细介绍了NASA对SiC纤维的改性工艺,对几种交联固化工艺作了简要介绍。最后概述了国内外SiC纤维发展现状以及前景展望。
关键词 SIC纤维 近分子式当量 聚碳硅烷 CVD法 先驱体法 交联固化 抗氧化
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Investigation of the Influence of Annealing Temperature on the Morphology and Growth Kinetic of Ni3Sn4 in the Ni-Sn-Solder System 被引量:1
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作者 Mathias Wendt Andreas Plö&beta +3 位作者 l Andreas Weimar Marcus Zenger Klaus Dilger 《Journal of Materials Science and Chemical Engineering》 2016年第2期116-130,共15页
The reaction between high purity nickel (99.999%) and high purity tin (99.999%) was investigated in the temperature range of 232℃ - 330℃, at short periods of annealing (1 - 60 s). The reaction kinetic was studied us... The reaction between high purity nickel (99.999%) and high purity tin (99.999%) was investigated in the temperature range of 232℃ - 330℃, at short periods of annealing (1 - 60 s). The reaction kinetic was studied using cross-sectional scanning electron microscope (SEM) images. The intermetallic compound (IMC) growth was analyzed using the empirical power law and a time dependence in the range of 0.26 to 0.33 was found. The morphology of the IMC was investigated by SEM in the temperature range of 235℃ - 290℃, at annealing periods of 10 s, 30 s, and 60 s by selectively etching away the remaining elementary tin. The exposed IMC displays a change in morphology with increasing annealing temperature, demonstrating that the growth velocity of certain crystallographic orientations of the IMC is strongly influenced by the annealing temperature. Additionally, coarsening and crumbling of the IMC grains is observed, and will be discussed with respect to the responsible mechanisms. 展开更多
关键词 Lead-Free Solders Intermetallic Compound Formation Grain Growth COARSENING Solid Liquid Inter-Diffusion (SLID) Bonding
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ADO效率最好的练习——让您的ADO应用程序拥有最好的效率
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作者 Bill Vaughn Mathias Pan 《软件》 2001年第12期135-139,共5页
作者花了相当多的时间,研究出一些SQL Server数据存取的程序技巧、架构,以及要如何开发才能达到最好的效率。“效率”这个字有好几种不同以及隐含的含意。当某人提到某样东西的效率很好时,大部分可能是指在一段时间完成了许多的工作。例... 作者花了相当多的时间,研究出一些SQL Server数据存取的程序技巧、架构,以及要如何开发才能达到最好的效率。“效率”这个字有好几种不同以及隐含的含意。当某人提到某样东西的效率很好时,大部分可能是指在一段时间完成了许多的工作。例如,效率良好的引擎代表的是运转安静并且可以产生很大的扭力。您可以将类似的衡量标准放到您的开发团队中:效率良好的开发团队。 展开更多
关键词 ADO 应用程序 效率 数据库
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Molecular Dynamics, Physical Properties, Diffusion Coefficients and Activation Energy of the Lithium Oxide (Li-O) and Sodium Oxide (Na-O) Electrolyte (Cathode)
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作者 Alain Second Dzabana Honguelet Abel Dominique Eboungabeka Timothée Nsongo 《Advances in Materials Physics and Chemistry》 CAS 2024年第9期213-234,共22页
This work is a simulation model with the LAMMPS calculation code of an electrode based on alkali metal oxides (lithium, sodium and potassium) using the Lennard Jones potential. For a multiplicity of 8*8*8, we studied ... This work is a simulation model with the LAMMPS calculation code of an electrode based on alkali metal oxides (lithium, sodium and potassium) using the Lennard Jones potential. For a multiplicity of 8*8*8, we studied a gap-free model using molecular dynamics. Physical quantities such as volume and pressure of the Na-O and Li-O systems exhibit similar behaviors around the thermodynamic ensembles NPT and NVE. However, for the Na2O system, at a minimum temperature value, we observe a range of total energy values;in contrast, for the Li2O system, a minimum energy corresponds to a range of temperatures. Finally, for physicochemical properties, we studied the diffusion coefficient and activation energy of lithium and potassium oxides around their melting temperatures. The order of magnitude of the diffusion coefficients is given by the relation Dli-O >DNa-O for the multiplicity 8*8*8, while for the activation energy, the order is well reversed EaNa-O > EaLi-O. 展开更多
关键词 Molecular Dynamics Diffusion Coefficients Activation Energy Lithium Oxide Sodium Oxide Lennard Jones Potential Data File Atomic and Charge Models CATHODE LAMMPS
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Drought Effects on Early Growth and Mortality of Three Oak Species in the Upper Rhine Valley
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作者 Sandrine Brèteau-Amores 《American Journal of Climate Change》 2018年第2期336-354,共19页
Pedunculate oak and sessile oak are important natural species in the Upper Rhine Valley. The increasing mortality of these oak species has been observed since the 1980s in this region, mainly due to severe droughts. T... Pedunculate oak and sessile oak are important natural species in the Upper Rhine Valley. The increasing mortality of these oak species has been observed since the 1980s in this region, mainly due to severe droughts. Turkey oak is known to be highly productive and drought-resistant. The goal of this article is therefore to investigate the adaptability to drought of these three young oak species growing at the same site, and to show to what extent Turkey oak can be substituted for these native oak species. Stand measurements and retrospective analyses of radial growth were performed within the framework of the eight-year-old “Mooswald” afforestation experiment in order to determine stand volume, mortality and resistance/resilience to drought for each species. Turkey oak shows significantly higher stand volume and significantly lower mortality than sessile oak. Values of these two parameters for Turkey oak and sessile oak are not significantly different from those of pedunculate oak. However, Turkey oak is not more resistant to drought than the other oak species. Sessile oak has the highest mortality and the smallest stand volume, while pedunculate oak is the least resilient to drought. These results are only a trend that must be confirmed in older stand stages and investigation in young stands must continue, supported by better monitoring and improved tools. 展开更多
关键词 Forest Climate Change Case Study TREE-RING Lloret Index
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价格隐含增长率 揭示股价秘密
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《新财经》 2006年第2期108-112,共5页
投资者呼唤成熟的市场,但是成熟的市场也需要成熟的投资者。为此,《新财经》将从本期起和Beta策略工作室一道,将一系列国际上最先进的估值研究方法和指标介绍给国内的投资者,以帮助大家更好地了解、参与资本市场。我们的开篇,就从揭示... 投资者呼唤成熟的市场,但是成熟的市场也需要成熟的投资者。为此,《新财经》将从本期起和Beta策略工作室一道,将一系列国际上最先进的估值研究方法和指标介绍给国内的投资者,以帮助大家更好地了解、参与资本市场。我们的开篇,就从揭示股价秘密的最有力指标——价格隐含增长率(PIG) 展开更多
关键词 资本市场 《新财经》 投资者 股票价格 经济利润
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Molecular Dynamics, Diffusion Coefficients and Activation Energy of the Electrolyte (Anode) in Lithium (Li and Li+), Sodium (Na and Na+) and Potassium (K and K+)
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作者 Alain Second Dzabana Honguelet Timothée Nsongo +1 位作者 Bitho Rodongo Earvin Loumbandzila 《Modeling and Numerical Simulation of Material Science》 2024年第1期39-57,共19页
This work is a simulation modelling with the LAMMPS calculation code of an electrode based on alkali metals (lithium, sodium and potassium) using the MEAM potential. For different multiplicities, two models were studi... This work is a simulation modelling with the LAMMPS calculation code of an electrode based on alkali metals (lithium, sodium and potassium) using the MEAM potential. For different multiplicities, two models were studied;with and without gap. In this work, we present the structural, physical and chemical properties of the lithium, sodium and potassium electrodes. For the structural properties, the cohesive energy and the mesh parameters were calculated, revealing that, whatever the chemical element selected, the compact hexagonal hcp structure is the most stable, followed by the face-centred cubic CFC structure, and finally the BCC structure. The most stable structure is lithium, with a cohesion energy of -6570 eV, and the lowest bcc-hcp transition energy of -0.553 eV/atom, followed by sodium. For physical properties, kinetic and potential energies were calculated for each of the sectioned chemical elements, with lithium achieving the highest value. Finally, for the chemical properties, we studied the diffusion coefficient and the activation energy. Only potassium followed an opposite order to the other two, with the quantities with lacunae being greater than those without lacunae, whatever the multiplicity. The order of magnitude of the diffusion coefficients is given by the relationship D<sub>Li</sub> > D<sub>Na</sub> > D<sub>k</sub> for the multiplicity 6*6*6, while for the activation energy the order is reversed. 展开更多
关键词 Molecular Dynamics Diffusion Coefficients Activation Energy LITHIUM Alkali Metals MEAM Potential
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