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1.
The topical application of aspirin and omega-3 polyunsaturated fatty acids (PUFAs) may trigger the resolution of inflammation by inducing the biosynthesis of pro-resolvers such as lipoxins and resolvins while also avoiding the side effects of systemic aspirin intake. This study assessed the effect of enhanced granulation tissue (EGT) on periodontal tissue regeneration through the local application of aspirin and omega-3 PUFAs directly to granulation tissue (GT) during periodontal surgery. This randomized controlled experiment assesses 38 pockets in 19 patients. In every patient, two similar intrabony periodontal defects are treated with an open flap debridement, one with EGT (GT extracted, enhanced with aspirin and omega-3 PUFAs, and replaced) and the other with standard GT removal. Clinical attachment level (CAL) and probing pocket depth (PPD) are assessed at baseline and 2 and 6 months after surgery. The experimental protocol (EGT) results in a greater CAL gain as compared to that in the controls at 6 months (p < 0.05), while PPD reduction is not affected. The retained GT does not compromise healing. EGT is proposed as a promising, inexpensive, and simple method that may improve the outcome of periodontal regenerative treatment. However, the described protocol requires optimization and further assessment. Practical Applications : The biosynthesis of mediators including resolvins and lipoxins triggered by aspirin and omega-3 PUFAs promote the resolution of inflammation, eventually leading to faster regeneration of inflamed tissues. While granulation tissue is a necessary component in wound healing, enhancing granulation tissue with aspirin and omega-3 PUFAs results in CAL gain in the surgical treatment of periodontal defects. Retained granulation tissue does not compromise periodontal healing. The EGT strategy is an inexpensive and simple method that may improve the clinical outcomes of regenerative periodontal procedures.  相似文献   
2.
Twin screw granulation (TSG) is a new process of interest to the pharmaceutical community that can continuously wet granulate powders, doing so at lower liquid concentrations and with better product consistency than found by a high shear batch mixer. A considerable body of research has evolved over the short time since this process was introduced but generally with little comparison of results. A certain degree of confidence has been developed through these studies related to how process variables and many attributes of machinery configuration will affect granulation but some major challenges still lay ahead related to scalability, variations in the processing regimes related to degree of channel fill and the impact of wetting and granulation of complex powder formulations. This review examines the current literature for wet granulation processes studied in twin screw extrusion machinery, summarizing the influences of operational and system parameters affecting granule properties as well as strives to provide some practical observations to newly interested users of the technique.  相似文献   
3.
ABSTRACT

Improving the hydration resistance of CaO particle in manufacturing and application of free CaO-containing materials has practical significance. In this study, CaO granules was made from Ca(OH)2 particles, which were fabricated by the granulation method. The results showed that the hydration resistance of the CaO granules which was prepared under 1700?r?min?1 was the best, the CaO granules was sintered well in calcination process, the shell of CaO granules was relatively dense, which improves the hydration resistance of CaO granules, and the rate of hydration weight increment was 0.58% after placed in the air for 20 days under a temperature of 10–14°C and a relative humidity of 57–81%.  相似文献   
4.
大颗粒尿素造粒工艺简介   总被引:4,自引:0,他引:4  
介绍了大颗粒尿素造粒工艺,着重介绍了荷兰NSM公司的流化床造粒技术和法国K-T公司的流化床转鼓造粒(FDG)技术。  相似文献   
5.
广钢3#高炉大修炉渣处理工艺探讨与分析   总被引:1,自引:0,他引:1  
范彦军 《冶金丛刊》2003,(5):10-11,27
本文对处理高炉炉渣的图拉法工艺设计进行了总结,并对广钢3#高炉使用中出现的问题做了分析,生产实践表明,该工艺安全可靠,水渣质量好,而且有利于环境保护。  相似文献   
6.
季保德 《广东化工》2002,29(6):8-11
介绍在团粒法工艺的基础上,将尿素熔融成尿液进行喷浆造粒生产复合肥的过程中,存在的问题,原因及解决的对策。  相似文献   
7.
摘要:研究了焦粉粒度对烧结混合料制粒的影响,包括焦粉在制粒小球中的分布规律与混合料制粒效果。结果表明:粒度小于0.5mm焦粉主要起黏附粉作用,较为均匀地黏附到各粒级制粒小球中;粒度在0.5~1mm的焦粉作为核颗粒,分布在0.5~1mm、1~3mm制粒小球中的占比总和为81.3%,部分以共核形式存在于3~5mm及以上粒级的制粒小球中;粒度在1~3mm及以上粒级焦粉作为核颗粒分布于相同粒级与大一粒级的制粒小球中;粒度在1~3mm及以上粒级焦粉对烧结混合料制粒无明显影响,粒度小于1mm的焦粉会提高制粒后混合料中小粒径制粒小球的含量,不利于混合料制粒,应尽可能减少焦粉中粒度在05~1mm的含量,将焦粉中粒度小于0.5mm的质量分数控制在20%~30%。  相似文献   
8.
赵姝  柯望  陈洁  张燕平 《计算机应用》2014,34(10):2812-2815
为了实现复杂网络社团发现算法的复杂度和精确度间的均衡,提出一种基于聚类粒化的社团发现算法(CGCDA),将网络粒化获得的粒子视为一个社团,粒化结果即为对网络的社团划分。首先,将网络中的每个节点视为基本粒,通过初始粒化操作实现对网络的粒化;然后,针对获得的粒化集合中满足粒化系数的粒子进行聚类粒化操作,分层粒化直到不存在满足要求的粒子对;最后,将粒子对中的重叠节点视为孤立点,用邻居节点投票法把孤立节点归并到相应的粒子中,实现对复杂网络的社团划分。实验实现了Newman快速算法(NFA)、标号传播算法(LPA)和CGCDA。实验结果表明,CGCDA在四个基准数据集上可获得平均高于LPA 7.6%的模块度和低于NFA 96%的时间。CGCDA时间复杂度较低,获取的社团模块度较高,实现了社团发现时间和精确度的均衡,相比NFA、LPA总体性能更优。  相似文献   
9.
It is possible to link granulation rates to granule properties. The linkage is by multiple dimension population balance equations that, by means of simplifying assumptions, can be reduced to multiple one-dimensional (1-D) population balance equations (PBEs). Using simple physically based models, this paper demonstrates how multiple one-dimensional population balance equations can describe the results of high-shear granulation experiments of two different materials, calcium carbonate and lactose. Good agreement between experimental and simulated results was achieved enabling the granulation rates to be defined by two model parameters: the critical binder volume fraction and the aggregation rate constant. The modelling framework presented in this paper also provides a basis for the kinetic analysis of granulation experiments so that with further work, it is possible to determine the effect of process conditions and material properties on the model parameters.  相似文献   
10.
A novel nucleation apparatus is presented for the production of narrow sized nuclei from various powder and binder liquid combinations. Mono-sized binder liquid droplets are produced by a specially designed mono-disperse droplet generator. The droplet generator is positioned above a conveyor belt, transporting a powder bed through the spray zone of the droplet generator. By nucleating powder on a conveyer belt, the nucleation mechanism is completely separated from all other granulation mechanisms due to the lack of relative motion between primary particles and/or formed nuclei. Nucleation tests were performed using chalcopyrite and limestone powders with water as the binder liquid. At all operating conditions, the formed nuclei were found to originate from multiplicities of drops that merged on the powder bed surface. Investigation of the dynamics of nuclei formation showed that powder-binder liquid combinations with fast penetration dynamics result in less variation in the number of droplets from which nuclei originate. Smaller and more narrowly distributed nuclei were also achieved by increasing powder speed through the spray zone.  相似文献   
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