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1.
三聚硫氰酸单钠盐是一种新型的多官能团化精细化学品。介绍了三聚硫氰酸单钠盐的制备方法,以及其在橡胶硫化、橡胶与金属的硫化粘合等领域的应用研究进展。  相似文献   
2.
多堆厂址一级概率安全评价(PSA)研究中,机组数目的增加使得建模工作量剧增,给整个核电厂的风险评估带来困难。结合已有基础,本文研究了多堆厂址始发事件分析的筛选方法,提出利用堆芯损伤频率(CDF)上下限值评估方法,分析厂址内不同机组数对厂址CDF的影响。结果表明,双机组厂址适合优先进行具体分析。针对双机组核电站,对多堆厂址内各始发事件进行筛选。结果表明,丧失厂外电、丧失热阱等事件适合建模分析,并对其他筛选结果给出后续分析建议,为多堆厂址一级PSA后续事故序列建模工作提供了重要基础。  相似文献   
3.
Anti-washout and tissue adhesion properties are essential for the clinical application of injectable bone materials. In this study, we prepared calcium phosphate cement (CPC) with anti-washout and tissue adhesion properties and attempted to build covalent bonds between CPC and the amino groups in bone tissue under a self-regulating pH system in the CPC (acidic to basic). The results of push-out tests demonstrated that a significant enhancement (from 6.42 ± 0.76 N to 61.5 ± 4.09 N) in tissue adhesion was obtained with the addition of 6% (w/w) oxidized sodium alginate (OSA) in CPC. The FTIR, XRD, anti-washout test, XPS, pH test, and SEM results suggested that the synergistic effect of OSA-citric acid (CA) led to the formation of a three-dimensional gel network structure in the CPC, and the Schiff base reaction between aldehyde and amino groups induced adhesion between CPC and the bone tissue. Further, the addition of less OSA had no significant negative effect on the hydration properties of CPC. Our work aims to promote the development of injectable bone material in clinical applications.  相似文献   
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5.
This paper reports the thermal, morphological and mechanical properties of environmentally friendly poly(3-hydroxybutyrate) (PHB)/poly(butylene succinate) (PBS) and PHB/poly[(butylene succinate)-co-(butylene adipate)] (PBSA) blends, prepared by melt mixing. The blends are known to be immiscible, as also confirmed by the thermodynamic analysis here presented. A detailed quantification of the crystalline and amorphous fractions was performed, in order to interpret the mechanical properties of the blends. As expected, the ductility increased with increasing PBS or PBSA amount, but in parallel the decrease in the elastic modulus appeared limited. Surprisingly, the elastic modulus was found properly described by the rule of mixtures in the whole composition range, thus attesting mechanical compatibility between the two blend components. This unusual behavior has been explained as due to co-continuous morphology, present in a wide composition range, but also at the same time as the result of shrinkage occurring during sequential crystallization of the two components, which can lead to physical adhesion between matrix and dispersed phase. For the first time, the elastic moduli of the crystalline and mobile amorphous fractions of PBS and PBSA and of the mobile amorphous fraction of PHB at ambient temperature have been estimated through a mechanical modelling approach. © 2021 The Authors. Polymer International published by John Wiley & Sons Ltd on behalf of Society of Industrial Chemistry.  相似文献   
6.
针对目前蒸汽吞吐产量预测模型假设条件简单、普适性差等问题,一般采用测试法和类比法综合确定海上稠油油田蒸汽吞吐初期产量。由于目前海上油田通常只开展常规测试,无法直接获得热采开发初期产量。笔者提出海上稠油油田蒸汽吞吐初期产量确定新方法,建立蒸汽吞吐相对于常规开发的初期产量倍数预测模型,通过蒸汽吞吐产量倍数,将常规测试确定的产量转化为蒸汽吞吐产量。研究表明,蒸汽吞吐初期产量倍数主要受储集层渗透率、原油黏度、注入强度、蒸汽干度等因素影响,利用正交试验设计和多元回归等方法,建立海上稠油油田蒸汽吞吐初期产量倍数与油藏地质参数及注入参数之间的非线性预测模型,该模型经实际生产数据验证,预测误差小于5%,可靠性高,能够为海上稠油油田蒸汽吞吐初期产量的确定提供依据。  相似文献   
7.
为提升漆包线产品的技术水平与行业市场竞争力,使产品进入漆包线产品的高端市场,扩大公司漆包线新品种与技术储备,提升公司科研创新和新产品的研发能力,与客户合作开展对军工船舶发电机用特种漆包线的研制。根据特种漆包线的性能要求和关键技术,对其漆膜绝缘材料的选择、产品结构的设计与优化及研制的生产工艺技术进行探讨,研制出的特种漆包线通过对其性能考核,完全满足客户的各项性能指标要求。  相似文献   
8.
苏里格气田是中国典型的致密砂岩气藏,构造简单、平缓,横向非均质性强,有效储层与围岩声学特征差别小,地震响应不明显,常规地震监测方法预测难度大,但气田含气砂岩泊松比低,是地震气藏检测的有效参数。利用弹性全波形反演精度高和能处理复杂非均质介质的优势,反演地层拉梅常数、剪切模量和密度,并计算泊松比,从而进行气藏预测。重点阐述了苏里格气田多分量数据全波形反演初始模型建模、先验模型建模和地震数据预处理3个关键问题的处理方法。二维三分量数据反演和"甜点"预测结果表明:①对于具有强非均质性的苏里格气田,利用全波形反演获得精度较高的地层弹性参数能显著提高气藏预测的准确度;②苏里格地区构造简单、平缓,利用常规叠加速度并结合构造解释可以建立比较好的初始模型,从而有效地解决了周波跳跃和局部极小的难题;③先验知识的约束和地震数据的预处理是全波形反演成功应用于苏里格气田气藏检测的关键。  相似文献   
9.
Endoscopic submucosal dissection (ESD) provides strong therapeutic benefits for early gastrointestinal cancer as a minimally invasive treatment. However, there is currently no reliable treatment to prevent scar contracture resulting from ESD which may lead to cicatricial stricture. Herein, a multifunctional colloidal wound dressing to promote tissue regeneration after ESD is demonstrated. This sprayable wound dressing, composed of hydrophobized microparticles, exhibits the multifunctionality necessary for wound healing including tissue adhesiveness, blood coagulation, re‐epithelialization, angiogenesis, and controlled inflammation based on hydrophobic interaction with biological systems. An in vivo feasibility study using swine gastric ESD models reveals that this colloidal wound dressing suppresses fibrosis and accelerates wound healing. Multifunctional colloidal and sprayable wound dressings have an enormous therapeutic potential for use in a wide range of biomedical applications including accelerated wound healing after ESD, prevention of perforation, and the treatment of inflammatory diseases.  相似文献   
10.
Stickinessis an inherent textural property in many sugar-rich foods, which can be problematic to the processing of confectionery products. The adhesion between foods and contact surfaces during processing and consumption has not been well understood in academia or industry. The theories of adhesion were discovered by scientists in the adhesive field of study, some of which can explain the stickiness phenomenon of confections. This work reviewed these theories in the context of sugar-rich foods, followed by a survey on the sensory and instrumental analyses of stickiness. Furthermore, the contributions of ingredients, temperature, compression, and contact surfaces to sugar-rich food adhesion are highlighted.  相似文献   
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