shrinkage

收缩率
  • 文章类型: Journal Article
    荟萃分析通常基于随机效应模型进行,而在某些情况下,人们也可能会主张采用共同效应模型。可以通过根据共同(或至少非常相似)协议执行的两个“研究双胞胎”的示例给出一个这样的情况。在这里,我们调查了一对研究的荟萃分析的特殊情况,例如,总结了临床开发计划III期的两项验证性临床试验的结果。因此,我们关注的问题是,在多大程度上同质性或异质性可能是可辨别的,并包括已发表的(\"孪生\")对研究的实证调查。来自两项研究的一对估计仅提供很少的证据证明效应的同质性或异质性,和临时决策标准通常可能会产生误导。
    Meta-analyses are commonly performed based on random-effects models, while in certain cases one might also argue in favor of a common-effect model. One such case may be given by the example of two \"study twins\" that are performed according to a common (or at least very similar) protocol. Here we investigate the particular case of meta-analysis of a pair of studies, for example, summarizing the results of two confirmatory clinical trials in phase III of a clinical development program. Thereby, we focus on the question of to what extent homogeneity or heterogeneity may be discernible and include an empirical investigation of published (\"twin\") pairs of studies. A pair of estimates from two studies only provide very little evidence of homogeneity or heterogeneity of effects, and ad hoc decision criteria may often be misleading.
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  • 文章类型: Journal Article
    为解决海岛工程建筑材料短缺问题,解决固体废物的积累,并抑制地质聚合物的收缩,珊瑚废料被用作内部固化材料,用海水制备高性能海洋地质聚合物混凝土(MGC),海沙,和普通石灰石骨料(LsA)。本研究中使用的珊瑚粗骨料(CorA)的总孔隙率为50%至58.3%,内部孔径为50-400μm。在相对湿度(RH)为75%-85%的范围内,CorA的水解吸遵循两阶段模式,在90%RH以上变得非线性,在97%RH下200小时内释放出约85%的水分,展示内部固化的潜力。向MGC中添加少量的CorA通过提供内部固化水而增加了坍落度和凝结时间。然而,由于CorA含量超过30%,由于混合水减少和活化剂浓度升高,坍落度显著下降,而初始凝固时间略有减少。此外,在MGC中包含饱和的CorA显着降低了自收缩,较高的CorA含量(超过30%)导致早期阶段的轻微膨胀,并且在含量高于40%时几乎消除了收缩。与普通波特兰水泥相比,地质聚合物体系的干燥收缩率更大,这是由于毛细管压力压缩了产品框架,将较大的凝胶孔转化为较小的孔。此外,层状铝酸钙水合物(C-A-S-H)凝胶在低内部湿度条件下表现出更显著的蠕变特性。MGC中较高的CorA含量促进了杂种C的形成,N-A-S-H凝胶和类水滑石相,减少碳酸化问题。CorA与地质聚合物基体之间的界面过渡区(ITZ)形成了坚固的机械互锁,提高抗拉强度和减少收缩引起的裂纹。根据总体性能和海洋材料利用率,建议CorA的最佳替代率在40%至50%之间。
    To address shortages in construction materials for island engineering, tackle the accumulation of solid waste, and inhibit the shrinkage of geopolymers, coral waste was utilized as the internal curing material to prepare high-performance marine geopolymer concrete (MGC) with seawater, sea-sand, and normal limestone aggregate (LsA). The coral coarse aggregate (CorA) used in this investigation has a total porosity ranging from 50% to 58.3% with internal pore diameters spanning 50-400 μm. The water desorption of CorA followed a two-stage pattern within a relative humidity (RH) range of 75%-85%, becoming nonlinear above 90% RH, which released about 85% of its moisture within 200 h at 97% RH, demonstrating potential for internal curing. Adding a small amount of CorA to MGC increased slump and setting time by providing internal curing water. However, as CorA content exceeded 30%, the slump significantly decreased due to reduced mixing water and elevated activator concentration, while the initial setting time slightly decreased. Furthermore, the inclusion of saturated CorA in MGC significantly reduced autogenous shrinkage, with higher CorA contents (exceeding 30%) leading to slight expansion in the early stages and nearly eliminating shrinkage at contents above 40%. The greater drying shrinkage in geopolymer systems compared to ordinary Portland cement is due to capillary pressure compressing the product framework, converting larger gel pores into smaller ones. Additionally, the layered calcium aluminosilicate hydrate (C-A-S-H) gel exhibits more pronounced creep characteristics under low internal humidity conditions. The higher CorA content in MGC promoted the formation of hybrid C, N-A-S-H gel and hydrotalcite-like phases, and reduced carbonation issues. The interfacial transition zone (ITZ) between CorA and the geopolymer matrix formed a robust mechanical interlock, enhancing tensile strength and minimizing shrinkage-induced cracks. Based on overall performance and marine material utilization, an optimal substitution rate of CorA between 40% and 50% is recommended.
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  • 文章类型: Journal Article
    花粉正在成为基因工程分子研究者越来越重要的课题,植物育种,和环境监测。为了扩大这些研究的范围,至关重要的是,为不擅长孢粉学的科学家开发可访问的方法。本文介绍了一种制备用于扫描电子显微镜(SEM)的花粉粒的简化技术程序。该方案是方便的任何分子实验室,由于其小的试剂集,易于执行,低成本,不需要特殊设备,只需要一个小时就能完成.甲醛的高渗透能力和使用六甲基二硅氮烷(HMDS)代替临界点干燥的最终精细脱水,可以充分保留孔的结构,这被认为是生物分子通过的门户。该方法已成功应用于双子叶植物(甜菜根,矮牵牛,萝卜,番茄和烟草)和单子叶植物(百合,洋葱,玉米,黑麦和小麦)。研究的物种包括昆虫授粉(嗜虫)和风授粉(嗜虫)物种。在光学显微镜下对新鲜活花粉粒的大小和为SEM准备的花粉粒的大小进行比较分析,显示出一些收缩。对花粉粒收缩程度的定量分析表明,这一过程取决于干燥花粉粒的初始形状,孔的数量和结构。结果支持花粉粒折叠/解折叠途径的理论模型。
    Pollen is becoming an increasingly important subject for molecular researchers in genetic engineering, plant breeding, and environmental monitoring. To broaden the scope of these studies, it is essential to develop accessible methods for scientists who are not specialized in palynology. The article presents a simplified technical procedure for preparing pollen grains for scanning electron microscopy (SEM). The protocol is convenient for any molecular laboratory due to its small set of reagents, ease of execution, low cost, does not require special equipment, and takes only one hour to complete. The high penetrating ability of formaldehyde and the final delicate dehydration using hexamethyldisilazane (HMDS) instead of critical point drying allow for sufficient preservation of the architecture of the aperture, which is considered a gateway for the passage of biomolecules. The method was successfully applied to pollen grains of representatives of dicotyledons (beetroot, petunia, radish, tomato and tobacco) and monocotyledons (lily, onion, corn, rye and wheat). Species studied included insect-pollinated (entomophilous) and wind-pollinated (anemophilous) species. A comparative analysis of the sizes of fresh living pollen grains under a light microscope and those prepared for SEM showed some shrinkage. Quantitative analysis of the degree of pollen grain shrinkage showed that this process depends on the initial shape of dry pollen grains, and the number and structure of apertures. The results support the theoretical model of the folding/unfolding pathways of pollen grains.
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  • 文章类型: Journal Article
    在这项研究中,探讨了高长径比纳米钙矾石对光固化环氧丙烯酸酯树脂的影响。使用γ-氨基丙基三乙氧基硅烷(KH-550)和γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH-570)对纳米钙矾石样品进行了改性。然后,3重量%或6重量%KH-550改性,KH-570改型,将未改性的纳米钙矾石样品通过超声处理和机械搅拌分散到树脂中。通过扫描电子显微镜(SEM)分析了纳米钙矾石在KH-550或KH-570上的接枝效果,傅里叶变换红外(FTIR)光谱,X射线衍射(XRD)和热重(TG)分析。结果表明,KH-550和KH-570已成功接枝到纳米钙矾石表面。此外,这项研究还侧重于复合材料的粘度变化,收缩,抗拉强度,和断裂伸长率。结果表明,未修饰的剂量增加,KH-550改型,和KH-570改性的纳米钙矾石导致复合材料的粘度增加,同时减少收缩。在相同的剂量下,含有KH-570改性的纳米钙矾石的可光固化树脂表现出较低的收缩率和较高的拉伸强度。从拉伸断裂表面的分析,据观察,与KH-550修饰和未修饰的变体相比,KH-570改性纳米钙矾石在光固化环氧丙烯酸酯树脂中具有优异的分散性。值得注意的是,当KH-570改性纳米钙矾石的量为3重量%时,复合材料的最高拉伸强度为64.61MPa,与空白样品相比,增加了72.57%。此外,KH-570改性纳米钙矾石作为填料的掺入为提高光固化环氧丙烯酸酯树脂复合材料的性能提供了新的视角。
    In this study, the impact of the addition of high-aspect-ratio nano-ettringite to photocurable epoxy acrylate resin was explored. The nano-ettringite samples were modified using γ-Aminopropyltriethoxysilane (KH-550) and γ-methacryloxypropyl trimethoxy silane (KH-570). Then, 3 wt% or 6 wt% KH-550-modified, KH-570-modified, and unmodified nano-ettringite samples were dispersed into resin via ultrasonic treatment in conjunction with mechanical stirring. The grafting effects of nano-ettringite onto KH-550 or KH-570 were analyzed through scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and thermogravimetric (TG) analysis. The results demonstrate that KH-550 and KH-570 have been successfully grafted onto the surface of nano-ettringite. In addition, this study also focuses on the variations of composite materials in the viscosity, shrinkage, tensile strength, and elongation at break. The results indicate that increased dosages of unmodified, KH-550-modified, and KH-570-modified nano-ettringite led to increased viscosity of the composite while reducing shrinkage. At the same dosage, the photocurable resin containing KH-570-modified nano-ettringite demonstrated a lower shrinkage and a higher tensile strength. From the analysis of tensile fracture surfaces, it was observed that compared to the KH-550 modified and unmodified variants, the KH-570 modified nano-ettringite exhibits superior dispersibility in photocurable epoxy acrylate resin. Notably, when the amount of KH-570-modified nano-ettringite was 3 wt%, the highest tensile strength of the composite was 64.61 MPa, representing a 72.57% increase compared to the blank sample. Furthermore, the incorporation of KH-570-modified nano-ettringite as a filler provides a new perspective for improving the performance of photocurable epoxy acrylate resin composites.
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  • 文章类型: Journal Article
    水凝胶的三维聚合物网络避免了其溶解到水性区域中。水凝胶必须具有强的结构完整性以用于药物/营养制品递送。使用三因素三水平Box-Behnken设计来了解淀粉浓度的影响,NaCl,和pH值对赖氨酸改性谷子淀粉水凝胶的质构和结构完整性的影响。各种动力学模型适用于常规(CDHG)和冷冻干燥(FDHG)水凝胶的收缩行为的时程测量。增加溶胀温度(5-50°C)显示,FDHG(9539.59-56,769.72)的相邻交联之间的聚合物链分子量(Mc)(g/mol)高于CDHG(1096.28-11,420.48)。同样,FDHG(38.63-109.53)的网目尺寸(ζ)大于CDHG(10.97-42.74)。然而,FDHG(0.229-0.146)的其他网络参数,如聚合物体积分数(PVAp)低于CDHG(0.3882-0.222)。这些值表明与FDHG相比,CDHG的膨胀力低。热力学上,FDHG比CDHG消耗更少的能量来膨胀。研究表明,FDHG比CDHG具有更好的性能,可用于营养食品的输送。
    在线版本包含补充材料,可在10.1007/s13197-024-05953-x获得。
    Three-dimensional polymeric network of hydrogels avoids its dissolution into the aqueous region. Hydrogels must have strong structural integrity to be used for drug/nutraceutical delivery. A three factor-three-level Box-Behnken design was used to understand the effects of starch concentration, NaCl, and pH on the textural and structural integrity of Lysine modified kutki millet starch hydrogels. Various kinetic models were fitted to the time-course measurement of shrinkage behavior of both conventionally (CDHG) and freeze-dried (FDHG) hydrogel. Increasing the swelling temperature (5-50 °C) showed values of higher molecular weight of polymer chains between neighboring crosslinks ( M c ) ¯ (g/mol) for FDHG (9539.59-56,769.72) than CDHG (1096.28-11,420.48). Similarly, mesh size (ξ) was more for FDHG (38.63-109.53 Ȧ) than CDHG (10.97-42.74 Ȧ). However, other network parameters such as polymer volume fraction ( ∅ p ) was lower for FDHG (0.229-0.146) than CDHG (0.3882-0.222). These values suggest low swelling power of CDHG compared to FDHG. Thermodynamically, FDHG took less energy to swell than CDHG. The study showed that FDHG has better properties than CDHG and could be employed in nutraceutical delivery.
    UNASSIGNED: The online version contains supplementary material available at 10.1007/s13197-024-05953-x.
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  • 文章类型: Journal Article
    独立的纤维素纳米原纤维(CNF)膜具有在从潮湿条件干燥时由于毛细管干燥应力而收缩的自然倾向。这种收缩发生在两个径向方向,和垂直方向。在这项研究中,我们制备了两种类型的CNF膜-一种在限制条件下不允许在径向方向上收缩但在垂直方向上允许它,另一种具有11%的径向收缩但有限的垂直收缩。径向收缩导致比垂直收缩更多孔的结构,这带来了较差的氧气/湿气阻隔性能。然而,在简单的热压过程中,薄膜的密度和氧气渗透率收敛到类似的值。径向收缩导致膜的断裂应变和韧性提高140%和90%,同时显著牺牲强度和模量。扫描电子显微镜显示,径向收缩在核心结构中形成波状层,留下更多的自由空间,而垂直收缩形成更平坦的层。径向收缩可能在CNF膜的芯结构中产生比垂直收缩更厚的单层。这项研究的见解将有助于调整CNF薄膜及其复合材料的机械和阻隔性能。
    Standalone cellulose nanofibril (CNF) films have a natural tendency to shrink upon drying from wet conditions due to capillary drying stresses. This shrinkage happens in both the radial direction, and the vertical direction. In this study, we prepared two types of CNF films- one in a restrained condition that did not allow shrinkage in the radial direction but enabled it in the vertical direction and another with 11 % radial shrinkage but limited vertical shrinkage. The radial shrinkage led to a more porous structure than the vertical shrinkage, which brought about poorer oxygen/moisture barrier performance. However, the density and oxygen permeability of the films converged to a similar value upon a simple thermocompression process. Radial shrinkage resulted in 140 % and 90 % higher strain at break and toughness in films with a significant sacrifice in strength and modulus. Scanning electron microscopy revealed that radial shrinkage formed wavy layers in the core structure leaving more free space, whereas vertical shrinkage formed flatter layers. Radial shrinkage is likely to produce a thicker individual layer in the core structure of CNF films than vertical shrinkage. The insight from this study will help tune the mechanical and barrier performance of CNF films and their composites.
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  • 文章类型: Journal Article
    建筑业发展迅速,导致对建筑材料的需求增加。用普通波特兰水泥(OPC)制成的混凝土长期以来一直是首选,因为它具有出色的粘合性能和施工过程所要求的多功能性。然而,普通硅酸盐水泥(OPC)的制造会对环境产生负面影响,水泥行业占全球二氧化碳排放量的5-8%左右。此外,OPC的制造需要大量的天然原材料和能源。相反,使用地质聚合物有望节省大量能源并减少二氧化碳排放。这种潜力激发了人们对在运输基础设施中应用地质聚合物的兴趣。对于人行道,可加工性要求较低,因此,地质聚合物混凝土(GPC)是一种可行的选择,但是GPC的抗疲劳性没有文献报道。本文评估了低钙粉煤灰的地质聚合物混凝土的性能,部分用8MNaOH碱性溶液的磨碎颗粒高炉矿渣(GGBS)代替,并在环境大气条件下固化,以评估其在路面中的使用情况,并开发一种环境可持续和耐用的GPC能够承受重型交通。该研究涉及调整路面质量混凝土(PQC)配合比设计;评估力学特性,耐磨性,和收缩应变的GPC;并分析其微观结构。此外,该研究使用各种威布尔分布方法比较了GPC和PQC的疲劳寿命。结果表明,GPC4(70%粉煤灰和30%GGBS)混合物在28天取得了最好的结果,抗压强度为45.68MPa,劈裂抗拉强度为3.76MPa,抗弯强度为4.62MPa。此外,在90天时,收缩菌株比PQC低近31%。此外,开发GPC需要比PQC少27%的体现能量。疲劳分析证明,在中等载荷下,具有8MNaOH的环境固化粉煤灰-GGBS基地质聚合物混凝土的应力发展小于PQC,尽管它很脆。因此,研究证明,它适合作为路面材料,以抵抗中等荷载的交通阻力路面。
    The building sector is growing at a rapid rate, leading to an increased demand for construction materials. Concrete made with Ordinary Portland Cement (OPC) has long been the preferred choice due to its excellent bonding properties and versatility as demanded by construction process. However, the manufacturing of Ordinary Portland Cement (OPC) leads to negative impacts on the environment, with the cement sector responsible for around 5-8% of global CO2 emissions. In addition, the manufacture of OPC necessitates significant amounts of natural raw materials and energy. Contrastingly, using geopolymers promises to save substantial amounts of energy and reduce CO2 emissions. This potential has sparked growing interest in the application of geopolymers within transportation infrastructure. For pavements, the workability requirement is less, and hence, geopolymer concrete (GPC) is a viable option, but fatigue-resistance of GPC is not seen reported in literatures. This article evaluates the properties of geopolymer concrete with low-calcium fly ash partially replaced with ground granular blast furnace slag (GGBS) with 8 M NaOH alkaline solution and cured under ambient atmospheric conditions to evaluate its usage in pavements and develop an environmentally sustainable and durable GPC capable of withstanding heavy traffic. The study involves adjusting the pavement quality concrete (PQC) mix design; evaluating the mechanical characteristics, abrasion resistance, and shrinkage strain of the GPC; and analyzing its microstructure. Additionally, the study compares the fatigue life of GPC to that of PQC using various Weibull distribution approaches. The results showed that GPC4 (70% Fly ash and 30% GGBS) mix achieved best results at 28 days, with a compressive strength of 45.68 MPa, split tensile strength of 3.76 MPa, and flexural strength of 4.62 MPa. Also, shrinkage strains were nearly 31% lesser than PQC at 90 days. In addition, developing GPC needs 27% lesser embodied energy than PQC. Fatigue analysis prove that ambient cured fly ash-GGBS based geopolymer concrete with 8 M NaOH exhibits less stress development than PQC at medium loads, even though it is brittle. Thus, the study proves that it is suitable as a material for pavements to resist medium-loaded traffic-resisting pavements.
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  • 文章类型: Journal Article
    雪莲根中富含低聚果糖(FOS),易腐烂。干燥对于食品质量和延长保质期至关重要。然而,保存热敏化合物,比如FOS,在常规干燥方法中提出了挑战。在这方面,微波干燥和乙醇预处理(ET)已成为保持营养和减少干燥时间(DT)的有前途的解决方案。这项研究的目的是评估ET和样品温度如何影响yacon间歇微波干燥过程中的质量和工艺参数。用乙醇处理的52°C干燥是表现出最高果聚糖保留率(64.1%)的一种,低DT,更低的能耗(EC)(364.00±5.03kWhkg水-1),更高的抗氧化能力(73.9%)和总酚含量(77.5%),和颜色参数的轻微变化。因此,用乙醇预处理的yacon控制温度的微波干燥可通过保持质量参数有效降低DT和EC。
    The yacon roots are rich in fructooligosaccharides (FOS) and highly perishable. Drying is crucial for food quality and extending shelf life. However, preserving thermosensitive compounds, such as FOS, poses a challenge in conventional drying methods. In this regard, microwave drying and ethanol pretreatment (ET) have emerged as promising solutions for maintaining nutrients and reducing drying time (DT). The objective of this study was to assess how ET and sample temperature affect quality and process parameters during intermittent microwave drying of yacon. Drying at 52°C treated with ethanol was the one that stood out for presenting the highest fructan retention (64.1%), low DT, lower energy consumption (EC) (364.00 ± 5.03 kWh kg water-1), higher retention of antioxidant capacity (73.9%) and total phenolic content (77.5%), and slight variation in color parameters. Therefore, microwave drying with a controlled temperature of yacon pretreated with ethanol effectively reduces DT and EC by maintaining quality parameters.
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  • 文章类型: Journal Article
    添加双向交互是统计学中的经典问题,并伴随着二次增加维度的挑战。我们的目标是a)设计一种可以应对这一挑战的估计方法,b)通过开发用于量化变量重要性的计算工具来帮助解释所得模型。
    现有策略通常通过仅允许相关主要效应之间的相互作用来克服维度问题。在这种哲学的基础上,并针对具有适度n-p比率的设置,我们建立了一个局部收缩模型,将相互作用效应的收缩与它们相应的主效应的收缩联系起来。此外,我们推导了Shapley值的一个新的解析公式,这允许快速评估个体特定变量重要性评分及其不确定性。
    我们凭经验证明,我们的方法提供了对模型参数的准确估计和非常有竞争力的预测准确性。在我们的贝叶斯框架中,估计本身就伴随着推理,这有助于变量选择。提供与主要竞争对手的比较。大规模队列数据用于提供现实的插图和评估。我们的方法在RStan中的实现相对简单和灵活,允许适应特定需求。
    我们的方法是处理流行病学和/或临床研究中相互作用的现有策略的一种有吸引力的替代方法。由于其链接的局部收缩可以提高参数精度,预测和变量选择。此外,它提供了适当的推论和解释,并且可能在预测方面与解释性较低的机器学习者竞争得很好。
    UNASSIGNED: The addition of two-way interactions is a classic problem in statistics, and comes with the challenge of quadratically increasing dimension. We aim to a) devise an estimation method that can handle this challenge and b) to aid interpretation of the resulting model by developing computational tools for quantifying variable importance.
    UNASSIGNED: Existing strategies typically overcome the dimensionality problem by only allowing interactions between relevant main effects. Building on this philosophy, and aiming for settings with moderate n to p ratio, we develop a local shrinkage model that links the shrinkage of interaction effects to the shrinkage of their corresponding main effects. In addition, we derive a new analytical formula for the Shapley value, which allows rapid assessment of individual-specific variable importance scores and their uncertainties.
    UNASSIGNED: We empirically demonstrate that our approach provides accurate estimates of the model parameters and very competitive predictive accuracy. In our Bayesian framework, estimation inherently comes with inference, which facilitates variable selection. Comparisons with key competitors are provided. Large-scale cohort data are used to provide realistic illustrations and evaluations. The implementation of our method in RStan is relatively straightforward and flexible, allowing for adaptation to specific needs.
    UNASSIGNED: Our method is an attractive alternative for existing strategies to handle interactions in epidemiological and/or clinical studies, as its linked local shrinkage can improve parameter accuracy, prediction and variable selection. Moreover, it provides appropriate inference and interpretation, and may compete well with less interpretable machine learners in terms of prediction.
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  • 文章类型: Journal Article
    为了进一步降低表面自由能,以获得更好的抗菌粘附效果的氟化二甲基丙烯酸酯(FDMA)/三环(5.2.1.0)癸二甲醇二丙烯酸酯(SR833s)基牙科树脂复合材料(DS),1H,甲基丙烯酸1H-七氟丁酯(FBMA)用于部分代替SR933s作为反应性稀释剂。根据替代程度,将获得的树脂复合材料标记为DSF-1(20wt.%的SR833被FBMA取代),DSF-2(40重量。%的SR833被FBMA取代),和DSF-3(60重量%。%的SR833s被FBMA取代)。使用双酚A二甲基丙烯酸缩水甘油酯(Bis-GMA)/三甘醇二甲基丙烯酸酯(TEGDMA)基树脂复合物(BT)作为对照。FBMA浓度对双键转化率(DC)的影响,接触角,表面自由能,对变形链球菌的抗菌粘附作用(S.mutans),体积收缩(VS)和收缩应力(SS),弯曲强度(FS)和模量(FM),研究了吸水率(WS)和溶解度(SL)。结果表明,添加FBMA可以将DS的表面自由能从44.6mN/m降低到DSF-3的32.9mN/m,并导致更好的抗菌粘附效果(粘附细菌的数量从2.03×105CFU/mm2减少DS到DSF-3的6.44×104CFU/mm2)。FBMA对DC没有负面影响,VS,SS,WS,和SL。过高浓度的FBMA在浸水前降低了FS和FM,但该值仍高于BT。
    With the purpose of further reducing surface free energy to achieve better anti-bacterial adhesion effect of fluorinated dimethacrylate (FDMA)/tricyclo (5.2.1.0) decanedimethanol diacrylate (SR833s) based dental resin composites (DS), 1H,1H-heptafluorobutyl methacrylate (FBMA) was used to partially replace SR933s as reactive diluent. According to the degree of substitution, the obtained resin composites were marked as DSF-1 (20 wt.% of SR833s was replaced by FBMA), DSF-2 (40 wt.% of SR833s was replaced by FBMA), and DSF-3 (60 wt.% of SR833s was replaced by FBMA). Bisphenol A glycidyl dimethacrylate (Bis-GMA)/triethylene glycol dimethacrylate (TEGDMA) based resin composite (BT) was used as control. The influence of FBMA concentration on double bond conversion (DC), contact angle, surface free energy, anti-bacterial adhesion effect against Streptococcus mutans (S. mutans), volumetric shrinkage (VS) and shrinkage stress (SS), flexural strength (FS) and modulus (FM), water sorption (WS) and solubility (SL) were investigated. The results showed that FBMA addition could reduce surface free energy from 44.6 mN/m for DS to 32.9 mN/m for DSF-3, and lead to better anti-bacterial adhesion effect (the amounts of adherent bacteria decreased from 2.03 × 105 CFU/mm2 for DS to 6.44 × 104 CFU/mm2 for DSF-3). The FBMA had no negative effects on DC, VS, SS, WS, and SL. Too high a concentration of FBMA reduced FS and FM before water immersion, but the values were still higher than those of BT.
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