physical property

物理性质
  • 文章类型: Journal Article
    刨花板在全球市场上获得了关注。由于粘合剂聚合,了解它们在当前技术环境中的物理机械行为至关重要,这取决于变量,如压制时间和温度。今天,纳米粒子的使用已成为一种合理的选择,以改善木基复合材料中使用的聚合物的性能。这项研究评估了使用具有较低环境影响的绿色路线添加非商业0.5%氧化铝(Al2O3)和氧化铝铜(CuO)纳米颗粒的影响,获得了基于脲甲醛(UF)的聚合物粘合剂,以制造桉树的颗粒复合材料。Grandiswood.关于表征,树脂性能分析为粘度,凝胶时间,pH值,以及面板属性,包括密度,水分含量,厚度膨胀,弹性模量,断裂模量,和导热性。将结果与科学出版物和标准进行比较。纳米粒子的加入会干扰粘度,并且所有处理指示碱性pH。不可能确定10分钟后的凝胶时间。在内层中添加到聚合物中的纳米颗粒不会引起厚度方面的溶胀性能的改善,密度和含水率无显著统计学差异。从150°C升高到180°C可能导致所有物理机械性能的改善,表明较高的温度对甲醛基粘合剂的聚合有积极的影响。因此,添加两种纳米颗粒(每种条件下均为0.5%)导致材料对物理机械性能的影响受到限制。
    Particleboards have gained attention in the global market. Understanding their physical-mechanical behavior in the current technological context is essential due to adhesive polymerization, which depends on variables such as pressing time and temperature. Today, the use of nanoparticles has become a plausible option for improving the properties of polymers used in wood-based composites. This study evaluates the influences of the addition of non-commercial 0.5% aluminum oxide (Al2O3) and aluminum oxide copper (CuO) nanoparticles using a greener route with a lower environmental impact obtaining a urea-formaldehyde (UF)-based polymeric adhesive to manufacture particle composites of Eucalyptus urophylla var. grandis wood. Regarding characterizations, the resin properties analyzed were viscosity, gel time, and pH, as well as panel properties, including density, moisture content, thickness swelling, modulus of elasticity, modulus of rupture, and thermal conductivity. The results were compared with scientific publications and standards. The addition of nanoparticles interfered with viscosity, and all treatments indicated a basic pH. It was not possible to determine the gel time after 10 min. Nanoparticles added to the polymers in the internal layer did not cause an improvement in the swelling properties in terms of thickness, with no significant statistical difference for density and moisture content. The increase from 150 °C to 180 °C may have caused an improvement in all physical-mechanical properties, indicating that the higher temperature positively influenced the polymerization of the formaldehyde-based adhesive. Therefore, the additions of both nanoparticles (0.5% in each condition) led to a limitation in the material influence with respect to physical-mechanical performance.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    矫正器的临床应用伴随着聚合物矫治器和所用附件的老化,这可能导致达到预测的牙齿移动范围的效率低下,以及由于摩擦而在口腔中释放化合物和微塑料,对准器和复合材料附件的磨损和磨损。这篇综述的目的是介绍体内老化的机制和影响;描述对齐剂的水解降解和复合附件的酶降解;检查对齐剂在体内的老化模式,在实际临床情景下;并确定与预测和实际临床结果之间的差异的联系。最后,处理与使用矫正器相关的三个潜在关键问题的策略,即每周更新的必要性,矫正器和附件的不同机械性能导致矫正器的磨损和塑性变形,以及随着设备的微生物定植而形成的覆盖层和生物膜,正在讨论。
    The clinical application of aligners is accompanied by the ageing of the polymer appliances and the attachments used, which may result in inefficiency in reaching the predicted range of tooth movement, and release of compounds and microplastics in the oral cavity as a result of the friction, wear and attrition of the aligner and composite attachment. The purpose of this review is to present the mechanism and effects of in vivo ageing; describe the hydrolytic degradation of aligners and enzymatic degradation of composite attachments; examine the ageing pattern of aligners in vivo, under actual clinical scenarios; and identify a link to the discrepancy between predicted and actual clinical outcome. Lastly, strategies to deal with three potentially critical issues associated with the use of aligners, namely the necessity of weekly renewal, the dissimilar mechanical properties of aligner and attachment resulting in wear and plastic deformation of the aligner, and the development of integuments and biofilms with microbial colonization of the appliance, are discussed.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    该研究旨在对泡腾系统中五种常用酸源的物理制造特性进行指纹分析,以设计此类系统的配方和工艺。吸湿性,纹理属性,流变扭矩,可压缩性,可压制性,等。,进行了调查,以检查“粉末直接压缩(DC)”和“湿法制粒和压缩”柠檬酸(CA)的性质,酒石酸(TA),苹果酸(MA),富马酸(FA),和己二酸(AA)。通过SeDeM专家系统评估DC能力。结果表明,所有酸性粉末均不符合DC的流动性要求,在压缩过程中塑性变形占主导地位。此外,CA具有很强的吸湿性和冲头粘附性,而MA表现出最佳的可压性。TA具有大的湿法制粒空间并且相对地最适合于DC。AA非常吸湿,并且其流动性随着颗粒尺寸的增加而显著改善。最后,FA显示出最低的吸湿性和弹射力以及巨大的可压缩性和湿颗粒空间,并且没有表现出冲头粘附,而颗粒碎片在崩解过程中缓慢溶解。一般来说,配方或制粒影响可压片性,这表明与其他酸或合适的填料配对可能会改善其缺点。这些多层面评估有效地减少了预勘探,并提高了泡腾系统开发的效率。
    The study aimed to fingerprint the physical manufacturing properties of five commonly used acid sources in effervescent systems for designing the formulation and process of such systems. The hygroscopicity, texture properties, rheological torque, compressibility, tabletability, etc., were investigated to inspect \'powder direct compression (DC)\' and \'wet granulation and compression\' properties of citric (CA), tartaric (TA), malic (MA), fumaric (FA), and adipic acid (AA). The DC ability was evaluated by the SeDeM expert system. The results indicated that all acid powders failed to meet flowability requirements for DC, and plastic deformation dominated during compression. Furthermore, CA exhibited strong hygroscopicity and punch sticking, while MA demonstrated the best tabletability. TA had a large wet granulation space and was relatively the most suitable for DC. AA was extremely hygroscopic, and its flowability improved significantly as particle size increased. Finally, FA displayed the lowest hygroscopicity and ejection force as well as great compressibility and wet granulation space, and did not exhibit punch sticking, while the granule fragments dissolved slowly during disintegration. Generally speaking, the formulation or granulation affected the tabletability, indicating that pairing with other acids or suitable fillers could potentially improve its disadvantages. These multidimensional assessments effectively reduce the pre-exploration and enhance the efficiency of the development of effervescent systems.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    近年来,食品和包装行业共同努力,尽量减少食物浪费。水果和蔬菜副产品,它们被认为是最丰富的食物垃圾之一,也是生物活性化合物的重要来源,有潜力改善食品的包装性能。石榴皮在食品活性包装中的抗氧化和抗菌性能一直是众多研究的主题。石榴皮对薄膜的微观结构和物理性能有影响,如厚度,水蒸气渗透性,机械性能,光学性质,和热性能。此外,石榴皮掺入膜表现出良好的抗氧化和抗菌性能。回顾含石榴皮的活性包装膜的物理和功能特性的当前进展是本研究的目标。
    In recent years, food and packaging industries have worked together to minimize food wastes. Fruit and vegetable by-products, which are known to be among the most abundant food wastes and a great source of bioactive compounds, have the potential to improve food product packaging properties. The antioxidant and antimicrobial properties of pomegranate peel in food active packaging have been the subject of numerous studies. Pomegranate peel has an impact on the films\' microstructure and physical properties, such as thickness, water vapor permeability, mechanical properties, optical properties, and thermal properties. Moreover, pomegranate peel incorporated films demonstrate great antioxidant and antimicrobial properties. Reviewing current advancements in the physical and functional properties of active packaging films containing pomegranate peel is the goal of this study.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    脂质结晶过程影响脂质的特性。通过改变脂质系统的化学成分,结晶行为是可以控制的。这篇综述阐明了影响脂质结晶的内部因素,包括三酰甘油(TAG)结构,标签组成,和次要成分。这些因素对TAG晶体多晶型的影响,纳米结构,微观结构,和物理性质进行了讨论。这些因素的相互作用共同影响各种规模的结晶。脂肪酸链长的变化,双键,和分支,以及它们在甘油骨架上的排列,指示TAG分子内部和之间的分子相互作用。高熔点TAG主导结晶,而液体油阻碍了这一过程,但促进了多晶型转变。独特的分子相互作用来自特定的TAG组合,产生具有独特性质的分子化合物。纳米级结晶受到液体油和次要组分的显著影响。TAG和次要组分之间的相互作用决定了次要组分对结晶过程的影响。此外,还提出了更好地设计和控制脂质结晶的未来观点。
    The process of lipid crystallization influences the characteristics of lipid. By changing the chemical composition of the lipid system, the crystallization behavior could be controlled. This review elucidates the internal factors affecting lipid crystallization, including triacylglycerol (TAG) structure, TAG composition, and minor components. The influence of these factors on the TAG crystal polymorphic form, nanostructure, microstructure, and physical properties is discussed. The interplay of these factors collectively influences crystallization across various scales. Variations in fatty acid chain length, double bonds, and branching, along with their arrangement on the glycerol backbone, dictate molecular interactions within and between TAG molecules. High-melting-point TAG dominates crystallization, while liquid oil hinders the process but facilitates polymorphic transitions. Unique molecular interactions arise from specific TAG combinations, yielding molecular compounds with distinctive properties. Nanoscale crystallization is significantly impacted by liquid oil and minor components. The interaction between the TAG and minor components determines the influence of minor components on the crystallization process. In addition, future perspectives on better design and control of lipid crystallization are also presented.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    β-葡聚糖是一种免疫增强剂,其生物活性与分子结构有关。在这个基础上,多糖可以被物理化学改性以产生有价值的功能材料。这项研究调查了修饰的β-葡聚糖的物理性质和免疫刺激活性。碱处理的β-葡聚糖具有明显的形状和比未处理的β-葡聚糖更小的粒度。减小的颗粒尺寸有利于悬浮液的稳定性,因为β-葡聚糖似乎通过这种处理完全溶解。形成无定形物质。此外,碱处理提高了β-葡聚糖的免疫刺激活性,而巨噬细胞暴露于热处理的β-葡聚糖会降低其免疫活性。通过湿磨具有减小的粒径的β-葡聚糖也表现出免疫调节活性。这些结果表明,β-葡聚糖的粒径是β-葡聚糖诱导的巨噬细胞免疫反应的关键因素。因此,β-葡聚糖颗粒大小的改变为将来开发免疫增强的营养品或药物疗法提供了新的机会。
    β-Glucan is an immunoenhancing agent whose biological activities are linked to molecular structure. On that basis, the polysaccharide can be physiochemically modified to produce valuable functional materials. This study investigated the physical properties and immunostimulatory activity of modified β-glucan. Alkali-treated β-glucan had a distinct shape and smaller particle size than untreated β-glucan. The reduced particle size was conducive to the stability of the suspension because the β-glucan appeared to be completely dissolved by this treatment, forming an amorphous mass. Furthermore, alkali treatment improved the immunostimulating activity of β-glucan, whereas exposure of macrophages to heat-treated β-glucan decreased their immune activity. β-Glucan with reduced particle size by wet-grinding also displayed immunomodulatory activities. These results suggested that the particle size of β-glucan is a key factor in β-glucan-induced immune responses of macrophages. Thus, the modification of the β-glucan particle size provides new opportunities for developing immunoenhancing nutraceuticals or pharmacological therapies in the future.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    简介:芒果籽粒(MSK)的提取物已被证明对革兰氏阳性和革兰氏阴性细菌具有抗菌活性,包括金黄色葡萄球菌和铜绿假单胞菌。这表明含有MSK提取物的生物材料可能是常规伤口治疗的可行替代方案。如纳米晶银敷料。尽管有这种潜力,在比较MSK膜敷料与纳米晶银敷料的抗菌效果的文献中存在显著的差距。本研究旨在开发含有MSK提取物的薄膜敷料,并与纳米晶银敷料相比评估其抗菌性能。此外,该研究旨在评估这些敷料对有效伤口护理至关重要的其他重要物理特性。材料和方法:我们从泰国的两个芒果品种中制备了MSK薄膜敷料,\'Chokanan\'和\'Namdokmai\'。采用抑制区法测定抗菌性能。用扫描电子显微镜(SEM)和傅里叶变换红外光谱(FTIR)对制备的MSK膜敷料进行了形貌和化学表征,分别。评估了薄膜敷料对假伤口渗出物的吸收和水蒸气透过率(WVTR)。结果:结果表明,40%的MSKC膜敷料具有最高的抑制区(对金黄色葡萄球菌为20.00±0.00mm,对铜绿假单胞菌为17.00±1.00mm)和20%,30%,40%的MSKC和MSKN膜敷料对金黄色葡萄球菌和铜绿假单胞菌具有与纳米晶银敷料相似的抑制区(p>0.05)。此外,所有浓度的MSK膜敷料都具有较低的吸收能力,ChokananMSK(MSKC)薄膜敷料的WVTR高于NamdokmaiMSK(MSKN)薄膜敷料。结论:20%,30%,40%的MSK薄膜敷料几乎与纳米晶银敷料一样有效。因此,它有可能成为替代抗菌敷料,适用于低渗出物水平的伤口。
    Introduction: The extract from the Mango Seed Kernel (MSK) has been documented to exhibit antibacterial activity against Gram-positive and Gram-negative bacteria, including Staphylococcus aureus and Pseudomonas aeruginosa. This suggests that biomaterials containing MSK extract could be a viable alternative to conventional wound treatments, such as nanocrystalline silver dressings. Despite this potential, there is a notable gap in the literature regarding comparing the antibacterial effectiveness of MSK film dressings with nanocrystalline silver dressings. This study aimed to develop film dressings containing MSK extract and evaluate their antibacterial properties compared to nanocrystalline silver dressings. Additionally, the study aimed to assess other vital physical properties of these dressings critical for effective wound care. Materials and methods: We prepared MSK film dressings from two cultivars of mango from Thailand, \'Chokanan\' and \'Namdokmai\'. The inhibition-zone method was employed to determine the antibacterial property. The morphology and chemical characterization of the prepared MSK film dressings were examined with scanning electron microscopy (SEM) and Fourier-Transform Infrared Spectroscopy (FTIR), respectively. The absorption of pseudo-wound exudate and water vapor transmission rate (WVTR) of film dressings were evaluated. Results: The results showed that 40% of MSKC film dressing had the highest inhibition zone (20.00 ± 0.00 mm against S. aureus and 17.00 ± 1.00 mm against P. aeruginosa) and 20%, 30%, and 40% of MSKC and MSKN film dressings had inhibition zones similar to nanocrystalline silver dressing for both S. aureus and P. aeruginosa (p > 0.05). In addition, all concentrations of the MSK film dressings had low absorption capacity, and Chokanan MSK (MSKC) film dressings had a higher WVTR than Namdokmai MSK (MSKN) film dressings. Conclusion: 20%, 30%, and 40% of MSK film dressing is nearly as effective as nanocrystalline silver dressing. Therefore, it has the potential to be an alternative antibacterial dressing and is suitable for wounds with low exudate levels.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    研究了高压处理对通过挤出工艺生产的基于大豆蛋白的高水分肉类似物(S-HMMA)的物理性质和可能的保质期延长的影响。在200、400和600MPa下施加高压处理5、10和15分钟。S-HMMA的物理性质,包括外观,水分含量,在4°C储存8周期间分析颜色和质地。更高的压力和更长的储存时间通过产生更多的空气单元和增加空化来显著降低水分含量。S-HMMA产物的L*值在较高加压水平下增加,而增加储存时间倾向于降低亮度。无压力控制的S-HMMA产品显示出增加的硬度和韧性,而经受各种压力的S-HMMA产品在200-400MPa下与对照样品相比随时间表现出更高的硬度和韧性。用高压(600MPa)处理的产品显示出最大的微生物生长减少,但豆类的香气变得更加明显。
    The effects of high pressure treatment were investigated on the physical properties and possible shelf-life extension of soy protein-based high moisture meat analog (S-HMMA) produced by the extrusion process. High pressure treatment was applied at 200, 400 and 600 MPa for 5, 10 and 15 min. Physical properties of S-HMMA including appearance, moisture content, color and texture were analyzed during storage at 4 °C for 8 weeks. Higher pressure and longer storage time significantly reduced moisture content by creating more air cells and increasing cavitation. L* value of S-HMMA products increased at higher levels of pressurization while increasing storage time tended to decrease lightness. The unpressurized control S-HMMA product showed increasing hardness and toughness, while S-HMMA products subjected to various pressures exhibited higher hardness and toughness over time compared to the control sample at 200-400 MPa. Products treated with high pressure (600 MPa) showed the highest reductions in microbial growth but the aroma of the beans became more pronounced.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

  • 文章类型: Journal Article
    在缓释微丸的开发过程中,丸芯的物理特性可影响制剂中的药物释放。提出了基于近红外(NIR)光谱和集成学习的方法来快速评估颗粒核的物理性质。在研究中,三种算法的潜力,直接标准化(DS),偏最小二乘回归(PLSR)和广义回归神经网络(GRNN),进行了调查和比较。DS的性能,在应用引导聚合(Bagging)集成学习后,PLSR和GRNN模型得到了改进。Bagging-GRNN模型显示出最佳的预测能力。除颗粒间孔隙率外,其他11个物理参数的平均绝对偏差均小于1.0.此外,使用Bagging-GRNN模型时,16个验证样本中有15个的实际指纹和预测物理指纹之间的余弦系数值高于0.98.为了降低模型的复杂性,60个变量与静止角显着相关,利用颗粒尺寸(D50)和圆度来建立简化的Bagging-GRNN模型。简化模型显示出令人满意的预测能力。总之,基于近红外光谱的开发集成建模策略是一种快速表征颗粒芯物理性质的有前途的方法。
    During the development of sustained-release pellets, the physical characteristics of the pellet cores can affect drug release in the preparation. The method based on near-infrared (NIR) spectroscopy and ensemble learning was proposed to swiftly assess the physical properties of the pellet cores. In the research, the potential of three algorithms, direct standardization (DS), partial least squares regression (PLSR) and generalized regression neural network (GRNN), was investigated and compared. The performance of the DS, PLSR and GRNN models were improved after applying bootstrap aggregating (Bagging) ensemble learning. And the Bagging-GRNN model showed the best predictive capacity. Except for inter-particle porosity, the mean absolute deviations of other 11 physical parameters were less than 1.0. Furthermore, the cosine coefficient values between the actual and predicted physical fingerprints was higher than 0.98 for 15 out of the 16 validation samples when using the Bagging-GRNN model. To reduce the model complexity, the 60 variables significantly correlated with angle of repose, particle size (D50) and roundness were utilized to develop the simplified Bagging-GRNN model. And the simplified model showed satisfactory predictive capacity. In summary, the developed ensemble modelling strategy based NIR spectra is a promising approach to rapidly characterize the physical properties of the pellet cores.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

    求助全文

  • 文章类型: Journal Article
    在这项研究中,通过三种方法加工并干燥了RubuschingiiHu(中文名称:Fu-Pen-Zi;FPZ)的干果-在阴凉处,太阳,还有烤箱.关于标准成分的成分,颜色,和抗氧化能力进行了前和后处理研究。使用顶空-固相微萃取-气相色谱-质谱(HS-SPME-GC-MS)和风味组学技术分析了FPZ的赋予风味的代谢物。获得的结果表明,在经过处理并在阴凉处干燥的FPZ果实中检测到最高的使用价值和抗氧化能力。共检出358种代谢物,主要由萜类化合物组成,杂环化合物,和酯类。在差异分析中,在所有三种干燥方法后,代谢物的下调远远大于其上调。在评估三种方法后产生的特征化合物和风味时,主要是关于绿色和水果气味的变化。因此,通过分析和比较FPZ水果加工前后检测到的化学成分的变化,可以为新型农业方法的开发以及在制药和化妆品行业中的应用获得相当多的见解。本文为水果的质量控制及其临床应用提供了科学依据。
    In this study, the dried fruits of Rubus chingii Hu (Chinese name: Fu-Pen-Zi; FPZ) were processed and dried by three methods-in the shade, the sun, and the oven. The composition regarding the standard ingredient, color, and antioxidant capacities were investigated pro- and post-processing. The technique of headspace-solid-phase-microextraction-gas-chromatography-mass spectrometry (HS-SPME-GC-MS) and flavoromics were used to analyze the flavor-conferring metabolites of FPZ. The results obtained revealed that the highest use value and antioxidant capacities were detected in the FPZ fruits processed and dried in the shade. A total of 358 metabolites were detected from them mainly consisting of terpenoids, heterocyclic compounds, and esters. In differential analysis, the down-regulation of the metabolites was much greater than their up-regulation after all three drying methods. In an evaluation of the characteristic compounds and flavors produced after the three methods, there were variations mainly regarding the green and fruity odors. Therefore, considerable insights may be obtained for the development of novel agricultural methods and applications in the pharmaceutical and cosmetic industries by analyzing and comparing the variations in the chemical composition detected pre- and post-processing of the FPZ fruits. This paper provides a scientific basis for quality control in fruits and their clinical applications.
    导出

    更多引用

    收藏

    翻译标题摘要

    我要上传

       PDF(Pubmed)

公众号