Pellets

颗粒
  • 文章类型: Journal Article
    残余木质纤维素生物质(RLB)是一种有价值的资源,可以通过作为化石燃料的替代品和作为生产各种增值分子的原料来帮助解决环境问题。为了全面了解南美木质纤维素废物的使用情况,过去四年进行了审查。审查的重点是能源生产,生物燃料生产,获得平台分子(如乙醇,羟甲基糠醛,糠醛,和乙酰丙酸),和其他感兴趣的材料。审查发现,巴西,哥伦比亚,厄瓜多尔的RLB来源最多,甘蔗,油棕,和水稻作物残留物是最突出的。在南美洲,RLB用于生产沼气,合成气,氢气,生物油,生物柴油,烘焙生物质,颗粒,和生物质煤块。研究和生产最多的增值分子是乙醇,其次是糠醛,羟甲基糠醛,和乙酰丙酸.用RLB开发的其他感兴趣的应用包括获得活性炭和纳米材料。南美洲在利用RLB方面取得了重大进展,一些国家在规范其使用方面更加积极主动。然而,关于每个国家RLB的潜力,还有很多需要了解的地方。这篇评论提供了有关南美残留生物量的典型化和价值化的最新观点,并讨论了该地区正在应用的研究和技术水平。这些信息可能有助于未来在南美洲的RLB研究。
    Residual lignocellulosic biomass (RLB) is a valuable resource that can help address environmental issues by serving as an alternative to fossil fuels and as a raw material for producing various value-added molecules. To gain a comprehensive understanding of the use of lignocellulosic waste in South America, a review was conducted over the last 4 years. The review focused on energy generation, biofuel production, obtaining platform molecules (such as ethanol, hydroxymethylfurfural, furfural, and levulinic acid), and other materials of interest. The review found that Brazil, Colombia, and Ecuador had the most RLB sources, with sugarcane, oil palm, and rice crop residues being the most prominent. In South America, RLB is used to produce biogas, syngas, hydrogen, bio-oil, biodiesel, torrefied biomass, pellets, and biomass briquettes. The most studied and produced value-added molecule was ethanol, followed by furfural, hydroxymethylfurfural, and levulinic acid. Other applications of interest that have been developed with RLB include obtaining activated carbon and nanomaterials. Significant progress has been made in South America in utilizing RLB, and some countries have been more proactive in regulating its use. However, there is still much to learn about the potential of RLB in each country. This review provides an updated perspective on the typification and valorization of residual biomass in South America and discusses the level of research and technology being applied in the region. This information can be helpful for future research on RLB in South America.
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  • 文章类型: Journal Article
    很大比例的药物现在被认为是多颗粒系统。修饰释放给药制剂可以设计成具有工程精度,和以患者为中心的给药可以使用多单元系统相对容易地完成。在许多情况下,多单位颗粒系统(MUPS)基于中性赋形剂核心来配制,所述核心可以携带也被功能性包衣包围的分层药物。在本摘要中,介绍了常用的发酵剂颗粒。手稿描述了与其微观和宏观结构相关的各种核的主要特性。在基于不同惰性颗粒芯形成的分层颗粒的情况下,药物释放机制可以详细预期。最后,作者希望通过介绍一些市售配方来证明惰性核心的工业意义。
    A significant proportion of pharmaceuticals are now considered multiparticulate systems. Modified-release drug delivery formulations can be designed with engineering precision, and patient-centric dosing can be accomplished relatively easily using multi-unit systems. In many cases, Multiple-Unit Pellet Systems (MUPS) are formulated on the basis of a neutral excipient core which may carry the layered drug surrounded also by functional coating. In the present summary, commonly used starter pellets are presented. The manuscript describes the main properties of the various nuclei related to their micro- and macrostructure. In the case of layered pellets formed based on different inert pellet cores, the drug release mechanism can be expected in detail. Finally, the authors would like to prove the industrial significance of inert cores by presenting some of the commercially available formulations.
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  • 文章类型: Comparative Study
    奥美拉唑是一种广泛使用的非处方(20毫克)质子泵抑制剂,通常作为口服肠溶包衣小丸提供,旨在在pH5.5及更高的条件下释放;然而,它对酸性pH敏感。在实践中胃pH值升高的可能性对患者来说非常高;因此,本研究的目的是研究pH升高对市售奥美拉唑微丸性能的影响.除了“胃”(pH1.2或4.5)和“肠”(pH7.4)相溶解测试外,还在pH范围为1.2至4.5的pH范围内进行了水吸收-重量损失(WU-WL)测试。通过单个颗粒尺寸和沉降时间测量确定了颗粒的物理特性范围,其次是修正的斯托克斯定律方程的应用。颗粒大小和密度的变异系数,和体积-密度测定系数(R2)作为涂层厚度和微观结构变化的描述符,肠溶聚合物的电离程度,已发现增塑剂的水溶性和分子量可用于解释WU-WL和溶出测试期间的商业延迟释放微丸行为。研究的商业延迟释放微丸显示了pH依赖性WU-WL结果。“胃相”在pH4.5下的微丸溶出试验显示,诺奇实验室奥美拉唑降解率最高(48.1%),Teva和UQUIFA延迟释放小丸的剂量损失的中间值(23.4%和17.1%),分别。已经发现实验室Liconsa颗粒是最不敏感的(3.2%的剂量损失)。此外,pH4.5的“胃相”溶出试验显着影响“肠相”期间奥美拉唑的释放。对于Liconsa实验室,发现在升高的胃pH下摄入所研究的肠溶包衣延迟释放微丸相关的治疗不足的风险最小,并且从UQUIFA和Teva到NoshLabs微丸有所增加。
    Omeprazole is a widely used over-the-counter (20 mg) proton pump inhibitor, usually supplied as oral enteric-coated pellets intended to release at pH 5.5 and higher; however, it is sensitive to acidic pH. The likelihood of elevated gastric pH in practice is very high for patients; thus, the aim of this study was to investigate the effect of elevated pH on the performance of commercial omeprazole pellets. Commercial enteric-coated delayed-release pellets were tested with water uptake-weight loss (WU-WL) test at pH range between 1.2 and 4.5 in addition to \"gastric\" (pH 1.2 or 4.5) and \"intestinal\" (pH 7.4) phase dissolution tests. The range of physical characteristics of pellets was determined with a single pellet size and sedimentation time measurement, followed by the application of modified Stokes\' Law equation. The coefficient of variation of pellet size and density, and volume-density determination coefficient (R2) as descriptors of coating thickness and microstructure variability, degree of ionisation of enteric polymers, aqueous solubility and molecular weight of plasticisers have been found useful to explain commercial delayed-release pellets behaviour during WU-WL and dissolution test. Investigated commercial delayed-release pellets demonstrated pH-dependent WU-WL results. \"Gastric phase\" dissolution testing of pellets at pH 4.5 showed the highest omeprazole degradation (48.1%) for Nosch Labs, intermediate values of dose loss (23.4% and 17.1%) for Teva and UQUIFA delayed-release pellets, respectively. Lab Liconsa pellets have been found as the least susceptible (3.2% of dose loss). Additionally, \"gastric phase\" dissolution test at pH 4.5 significantly influenced omeprazole release during the \"intestinal phase\". The risk of inadequate therapy associated with intake of investigated enteric-coated delayed-release pellets at elevated gastric pH has been found as minimal for Lab Liconsa and has increased from UQUIFA and Teva to Nosh Labs pellets.
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  • 文章类型: Journal Article
    Microplastics (MPs) are emerging and ubiquitous contaminants which have been gaining prominence since the last decade to nowadays. This is due to their possible adverse effects in aquatic ecosystems as well as the huge amount of plastic waste exponentially generated around the globe. Plastics may be introduced either directly to water bodies or indirectly to the aquatic systems by being carried by the wind, from emissions of contaminated effluents, and soil leaching, among other processes. In turn, these debris may interact with organic and inorganic contaminants, such as polycyclic aromatic hydrocarbons (PAHs), polybrominated diphenyl ethers (PBDEs) and trace constituents, and with microorganisms. Although the abundance of microplastics from South Atlantic waters is among the highest found worldwide, the number of studies in these marine waters regarding MP contamination is still scarce. Additionally, there still are no consensus on the best sampling conditions, which may be underestimating MPs. In this way, adequate MPs studies regarding their distribution, exposure levels, chemical and biological interactions are highly suggested in order to better understand both environmental and human health potential risks. This review assessed advances in sampling, analytical methodologies, characterization and understanding of MP sources in these marine waters in comparison to data from other regions around the globe.
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  • 文章类型: Journal Article
    颗粒消耗的增加导致用于颗粒制造的材料种类更广泛。因此,颗粒行业已经开始寻找替代产品,例如农业活动产生的废物,林业及相关产业,连同它们的组合,获得广泛的这些产品。此外,ENISO17225标准的生效使木屑颗粒市场(除其他类型外)成为工业和家庭用途的可能。因此,适合生物质使用的废物最近有所增加。在这项研究中,分析了10种不同原料的实验室制粒的主要特性。因此,我们专注于确定生物质市场适用性的质量标准的最限制性因素,取决于颗粒的种类。结果表明,所分析的颗粒之间存在相当大的差异,在几乎所有情况下都超过标准规定的限值,特别是关于灰分含量和N和S组成。所研究标准的要求,对某些因素要求很高,禁止这些致密废物进入附加值更高的市场。
    The rise in pellet consumption has resulted in a wider variety of materials for pellet manufacture. Thus, pellet industry has started looking for alternative products, such as wastes from agricultural activities, forestry and related industries, along with the combination thereof, obtaining a broad range of these products. In addition, the entry into force of EN ISO 17225 standard makes wood pellet market (among other types) possible for industry and household purposes. Therefore, wastes that are suitable for biomass use have recently increased. In this study, the main characteristics of ten kinds of laboratory-made pellets from different raw materials were analyzed. Thus, we have focused on the most limiting factors of quality standards that determine the suitability for biomass market, depending on the kind of pellet. The results showed considerable differences among the analyzed pellets, exceeding the limits established by the standard in almost all cases, especially concerning ash content and N and S composition. The requirements of the studied standard, very demanding for certain factors, disable the entry of these densified wastes in greater added value markets.
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  • 文章类型: Journal Article
    Microplastics are omnipresent in the marine environment and sediments are hypothesized to be major sinks of these plastics. Here, over 100 articles spanning the last 50 year are reviewed with following objectives: (i) to evaluate current microplastic extraction techniques, (ii) to discuss the occurrence and worldwide distribution of microplastics in sediments, and (iii) to make a comprehensive assessment of the possible adverse effects of this type of pollution to marine organisms. Based on this review we propose future research needs and conclude that there is a clear need for a standardized techniques, unified reporting units and more realistic effect assessments.
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