physicochemical property

物理化学性质
  • 文章类型: Journal Article
    堆肥添加剂可以显著增进绿色废物(GW)堆肥。然而,由于单期添加的作用持续时间短,其有效性有限。因此,这项研究提出了多周期相加模式来延长作用持续时间,加速木质纤维素降解,减少堆肥时间,提高产品质量。这项研究进行了六个处理(T1-T6),在嗜温期(MP)和冷却期(CP)期间引入复合添加剂(BLP)。每种处理始终如一地保持了GW干重的25%总BLP添加量,仅在不同时期的BLP分布发生变化。BLP的组成由Wbiochar:Wlactic:Wpond沉积物组成,比例为10:1:40。具体来说,T1在CP中添加了25%的BLP,T2在MP中添加了5%,在CP中添加了20%,T3在MP中添加了10%,在CP中添加了15%,T4在MP中增加了15%,在CP中增加了10%,T5在MP中添加了20%,在CP中添加了5%,和T6在MP中添加25%。在这项研究中,堆肥温度,pH值,电导率,总孔隙度,木质素的含量,纤维素,半纤维素,和营养,扫描电子显微镜图像,发芽指数,并详细介绍了不同细菌和真菌在门和属水平上的演替。结果表明,T4达到了两个嗜热期,并在短短25天内成熟。T4增强了木质纤维素的降解率(木质素:16-53%,纤维素:14-23%,半纤维素:9-48%)和改善的营养成分。上述结果,结合相关性分析和结构方程模型,表明T4可能促进优势细菌(变形杆菌,Firmicutes,放线菌,拟杆菌)通过调节堆肥的理化性质,并通过调节养分供应能力来促进优势真菌(子囊菌和担子菌)的生长。这最终导致更有利于木质纤维素降解和营养保存的微生物群落结构。总之,本研究揭示了单期和多期添加方法对GW堆肥的综合影响,为优化添加剂的使用和提高GW堆肥的效率和质量提供了有价值的依据。
    Composting additives can significantly enhance green waste (GW) composting. However, their effectiveness is limited due to the short action duration of a single-period addition. Therefore, this study proposes that multi-period additive modes to prolong the action duration, expedite lignocellulose degradation, reduce composting time, and enhance product quality. This study conducted six treatments (T1-T6), introducing a compound additive (BLP) during the mesophilic (MP) and cooling periods (CP). Each treatment consistently maintained 25% total BLP addition of GW dry weight, with variations only in the BLP distribution in different periods. The composition of BLP consists of Wbiochar: Wlactic acid: Wpond sediment in a ratio of 10:1:40. Specifically, T1 added 25% BLP in CP, T2 added 5% in MP and 20% in CP, T3 added 10% in MP and 15% in CP, T4 added 15% in MP and 10% in CP, T5 added 20% in MP and 5% in CP, and T6 added 25% in MP. In this study, composting temperature, pH value, electrical conductivity, total porosity, the contents of lignin, cellulose, hemicellulose, and nutrient, scanning electron microscopy images, germination index, and the successions of different bacteria and fungi at the phylum and genus levels were detailed. Results showed T4 achieved two thermophilic periods and matured in just 25 days. T4 enhanced lignocellulose degradation rates (lignin: 16-53%, cellulose: 14-23%, hemicellulose: 9-48%) and improved nutrient content. The above results, combined with correlation analysis and structural equation model, indicated that T4 may promote the development of dominant bacteria (Proteobacteria, Firmicutes, Actinobacteria, Bacteroidetes) by regulating compost physicochemical properties and facilitate the growth of dominant fungi (Ascomycota and Basidiomycota) by modulating nutrient supply capacity. This ultimately leads to a microbial community structure more conducive to lignocellulose degradation and nutrient preservation. In summary, this study reveals the comprehensive effects of single-period and multi-period addition methods on GW composting, providing a valuable basis for optimizing the use of additives and enhancing the efficiency and quality of GW composting.
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  • 文章类型: Journal Article
    具有明显收敛性的香烟会减少消费者的享受。然而,由于香烟的成分复杂,准确量化收敛性强度一直具有挑战性。为了解决这个问题,进行研究以开发一种在模拟口腔环境中评估收敛性强度的方法。采用标准感官评价方法测定了4种卷烟品牌的涩味强度。通过模拟吸烟过程制备主流烟雾吸收溶液(MS),并对其理化性质(如总酚含量和pH值)进行了分析。使用MFT-5000磨损试验机测试了五种溶液的润滑性能,并考察了影响卷烟收敛性的因素。结果表明,MS的总酚含量和pH值与收敛强度呈正相关和负相关。分别。特别是,MS的润滑性能与收敛强度显著相关,在测试过程中,相关系数受负载和速度的影响。该研究得出的结论是,与MS的总酚含量和pH值相比,摩擦系数是评估卷烟收敛程度的更可靠指标,为高档卷烟的收敛性评估和开发提供新的见解。
    Cigarettes with pronounced astringency can diminish consumers\' enjoyment. However, due to the complex composition of cigarettes, quantifying astringency intensity accurately has been challenging. To address this, research was conducted to develop a method for assessing astringency intensity in a simulated oral environment. The astringency intensity of four cigarette brands was determined using the standard sensory evaluation method. The mainstream smoke absorbing solution (MS) was prepared by simulating the cigarette smoking process, and its physicochemical properties (such as total phenol content and pH levels) were analyzed. The lubrication properties of the five solutions were tested using the MFT-5000 wear tester, and factors influencing cigarette astringency were examined. The findings showed that total phenol content and pH of MS were positively and negatively correlated with astringency intensity, respectively. Particularly, the lubrication properties of MS were significantly correlated with astringency intensity, and the correlation coefficient was affected by load and speed during testing. The study concluded that coefficient of friction was a more reliable measure for assessing the extent of astringency in cigarettes than the total phenol content and pH of MS, offering new insights into astringency evaluation and development of high-grade cigarettes.
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  • 文章类型: Journal Article
    为了研究重复干热处理(RDH)和连续干热处理(CDH)对马铃薯淀粉结构和理化特性的影响,马铃薯淀粉在130°C下连续重复处理3-18小时。结果表明,淀粉的结晶形式与原始B型一致。它的物理化学性质,比如膨胀力,透明度,峰值粘度(PV),最终粘度(FV),击穿(BD)和热性能(至,Tp,Tc,ΔT),趋于减少。同时,干热处理后溶解度和RS增加。此外,RDH处理的淀粉在分子量方面高于CDH处理的淀粉,结晶度膨胀力,透明度和最终粘度相同的处理时间。尽管如此,两者的热性能没有显著差异。同时,随着处理时间和周期数的增加,CDH处理9h和RDH处理5个周期的峰值后,抗性淀粉(RS)含量呈下降趋势,表明淀粉的整体消化率降低。总的来说,RDH对马铃薯淀粉的结构和理化性质的影响比CDH更显著。
    To investigate the effects of repeated dry heat treatment (RDH) and continuous dry heat treatment (CDH) on the structure and physicochemical and digestive properties of potato starch, potato starch was treated continuously and repeatedly at 130 °C for 3-18 h. The results showed that the crystalline form of starch was consistent with the original type B. Still, its physicochemical properties, such as swelling power, transparency, peak viscosity (PV), final viscosity (FV), breakdown (BD) and thermal properties (To, Tp, Tc, ΔT), tended to decrease. At the same time, solubility and RS increased after dry heat treatment. Moreover, RDH-treated starches were higher than CDH-treated ones in terms of molecular weight, crystallinity, swelling power, transparency and final viscosity for the same treatment time. Still, there was no significant difference between the thermal properties of the two. Meanwhile, the resistant starch (RS) content showed a downward trend after the peak value of 9 h of CDH treatment and five cycles of RDH treatment with increasing treatment time and the number of cycles, indicating a decrease in the overall digestibility of the starch. Overall, RDH had a more significant effect on potato starch\'s structure and physicochemical properties than CDH.
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  • 文章类型: Journal Article
    A field excavation of refusewitha short-termlandfillage from the Qingdao Xiaojianxi municipal solid waste (MSW) landfill was conducted. The physical composition and chemical properties of refuse with landfill ages of 1-4 years were studied, and the emission characteristics of odorous pollutants during the excavation period were monitored. The refuse aged 1-2 years has a higher proportion of combustible material than that the refuse aged 3-4 years, and the volatile content and calorific value in refuse aged 1-2 years were also higher than those in refuse aged 3-4 years, indicating that the refuse with a short-term landfill age was more suitable for incineration than refuse with a long-term landfill age. The pH and availablephosphorus (AP) gradually increased with increasing landfill age, while the total Kjeldahlnitrogen (TKN) and organic matter (OM) decreased. The contents of the heavy metals Cu, Zn, Ni, Pb and As generally decreased with landfill age, especially in refuse aged 2-4 years, whereas the Cr content showed no significant differences in refuse aged 1-4 years. The main odorous pollutants emitted during the excavation and screening periods were ammonia (NH3) and carbon disulfide (CS2), and the odor intensity of excavated refuse aged 1-3 years was higher than that of refuse aged 4 years. Under the condition of a small excavation area and continuous deodorization, the pollution intensity can meet the discharge standards of the factory boundary.
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  • 文章类型: Journal Article
    This study aimed to assess the effectiveness and safety of BellaGel implants after implantation in Asian women and inform surgeons of another option for use in breast augmentation and reconstruction. This study was conducted in eight hospitals from November 27, 2015 to April 30, 2018. All patients underwent augmentation mammoplasty or implant-based breast reconstruction with BellaGel implants. Complication rates were compared between groups, and the cumulative hazard function was compared using the Kaplan-Meier survival analysis. Implants were grouped by surface type, and the cumulative hazard functions of total complication cases were compared. The biomechanical properties of the BellaGel implant and other company representative implants were tested using a mechanical testing machine, and surface topography was analyzed using a 3D laser scanning confocal microscope. There was a significant difference in the incidence of complications between the reconstruction (17.1%) and augmentation (4.7%) groups, but no significant difference in the complication rates of each group. There was no difference in the reoperation or revision rates between the groups. The log rank test showed a statistically significant difference in cumulative hazard function between the groups. Among the three types of implants (smooth, textured, and microtextured), the microtextured type had the lowest complication rate. The BellaGel microtexture implant had the highest maximal tensile load and displacement value. The BellaGel and Silksurface implants had the highest stored energy, although there was no significant difference. BellaGel implants can serve as a criterion for the selection of safe and effective implants among currently available implants.
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  • 文章类型: Journal Article
    离子液体,作为可调谐的,高度可溶,不易燃,非挥发性和可重复使用的萃取剂,从植物中提取黄酮类化合物引起了广泛的关注。在目前的工作中,通过简单有效的方法合成了新型双链咪唑盐衍生的离子液体,并对其进行了表征(NMR光谱,热稳定性,粘度,电导率,和极性)。然后,采用不同阳离子咪唑离子液体微波辅助提取马尾松中黄酮类化合物。结果表明,离子液体[Bmbim]Br,具有相对较低的粘度,电导率和π*以及相对较大的β,提供了最佳的黄酮提取效率和选择性。随后,黄酮提取工艺参数优化为:提取温度为80℃,提取时间60min,300W的微波功率,固液比为1:20,[Bmbim]Br溶液浓度为1.0mol/L总黄酮的提取率为41.07mg/g。最后,已经证明了离子液体的回收方法,离子液体的回收率为73.14%。
    Ionic liquids, as tuneable, highly soluble, non-flammable, non-volatile and reusable extractants, have attracted extensive attention in the extraction of flavonoids from plants. In the present work, novel dual-chain imidazolium-derived ionic liquids were synthesized by a simple and efficient method and characterized (NMR spectroscopy, thermal stability, viscosity, conductivity, and polarity). Then, the imidazolium ionic liquids with different cation were used in the microwave-assisted extraction of flavonoids from Pinus massoniana Lamb. The results showed that the ionic liquid [Bmbim]Br, with a relatively low viscosity, conductivity and π* as well as a relatively large β, offered the best extraction efficiency and selectivity for flavonoids. Subsequently, the parameters of the extraction procedure for flavonoids were optimized as follows: extraction temperature of 80 °C, extraction time of 60 min, microwave power of 300 W, solid-liquid ratio of 1:20, and [Bmbim]Br solution concentration of 1.0 mol/L. The extraction yield of total flavonoids was 41.07 mg/g. Finally, a recovery method of the ionic liquid had been demonstrated, and the recovery rate of ionic liquid was 73.14%.
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  • 文章类型: Journal Article
    To manufacture a polycaprolactone (PCL)/type Ⅰ collagen (COL Ⅰ) tissue engineered meniscus scaffold (hereinafter referred to as PCL/COL Ⅰ meniscus scaffold) by three-dimensional (3D) printing with low temperature deposition technique and to study its physicochemical properties.
    First, the 15% PCL/4% COLⅠ composite solution and 15% PCL simple solution were prepared. Then, 15% PCL/4% COL Ⅰmeniscus scaffold and 15% PCL meniscal scaffold were prepared by using 3D printing with low temperature deposition techniques. The morphology and microstructure of the scaffolds were observed by gross observation and scanning electron microscope. The compression modulus and tensile modulus of the scaffolds were measured by biomechanical test. The components of the scaffolds were analyzed by Fourier transform infrared spectroscopy (FTIR). The contact angle of the scaffold surface was measured. The meniscus cells of rabbits were cultured with the two scaffold extracts and scaffolds, respectively. After cultured, the cell proliferations were detected by cell counting kit 8 (CCK-8), and the normal cultured cells were used as controls. Cell adhesion and growth of scaffold-cell complex were observed by scanning electron microscope.
    According to the gross and scanning electron microscope observations, two scaffolds had orientated 3D microstructures and pores, but the surface of the PCL/COLⅠ meniscus scaffold was rougher than the PCL meniscus scaffold. Biomechanical analysis showed that the tensile modulus and compression modulus of the PCL/COL Ⅰ meniscus scaffold were not significantly different from those of the PCL meniscus scaffold ( P>0.05). FTIR analysis results showed that COL Ⅰ and PCL were successful mixed in PCL/ COL Ⅰ meniscus scaffolds. The contact angle of PCL/COLⅠ meniscus scaffold [(83.19±7.49)°] was significantly lower than that of PCL meniscus scaffold [(111.13±5.70)°] ( t=6.638, P=0.000). The results of the CCK-8 assay indicated that with time, the number of cells cultured in two scaffold extracts showed an increasing trend, and there was no significant difference when compared with the control group ( P>0.05). Scanning electron microscope observation showed that the cells attached on the PCL/ COL Ⅰ meniscus scaffold more than that on the PCL scaffold.
    PCL/COLⅠmeniscus scaffolds are prepared by 3D printing with low temperature deposition technique, which has excellent physicochemical properties without cytotoxicity. PCL/COLⅠmeniscus scaffold is expected to be used as the material for meniscus tissue engineering.
    采用低温沉积技术 3D 打印制备聚己内酯(polycaprolactone,PCL)/Ⅰ型胶原组织工程半月板支架(以下简称 PCL/Ⅰ型胶原半月板支架),探讨其理化特性。.
    制备 15%PCL/4%Ⅰ型胶原溶液及 15%PCL 溶液,利用低温沉积技术 3D 打印制备 PCL/Ⅰ型胶原半月板支架及 PCL 半月板支架。大体及扫描电镜观察支架形态及微观结构,生物力学试验测量支架压缩模量及拉伸模量,红外光谱分析支架成分,测量支架表面接触角;将两种支架及其浸提液分别与兔半月板细胞复合培养,细胞计数试剂盒 8(cell counting kit 8,CCK-8)检测细胞增殖,并以正常培养细胞作对照;扫描电镜观察支架-细胞复合物中细胞黏附及生长情况。.
    大体及扫描电镜观察显示,两种支架均具有取向的三维微观结构及孔隙,但 PCL/Ⅰ型胶原半月板支架表面更粗糙。生物力学测试,两种支架压缩模量及拉伸模量比较,差异均无统计学意义( P>0.05)。红外光谱分析提示,PCL/Ⅰ型胶原半月板支架中 PCL 和Ⅰ型胶原成功混合。PCL/Ⅰ型胶原半月板支架表面接触角为(83.19±7.49)°,较 PCL 半月板支架(111.13±5.70)° 显著减小( t=6.638, P=0.000)。CCK-8 检测显示,随培养时间延长,两种支架浸提液培养的细胞数量呈递增趋势,与对照组比较差异均无统计学意义( P>0.05)。支架-细胞复合物扫描电镜观察示,PCL/Ⅰ型胶原半月板支架表面黏附细胞多于 PCL 半月板支架。.
    低温沉积技术 3D 打印制备的 PCL/Ⅰ型胶原半月板支架具有优良的理化学性能,无细胞毒性,有望作为半月板组织工程支架材料。.
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  • 文章类型: Journal Article
    Nymphaeaodorata的煮熟的心皮具有大量透明的粘液;但是,这种粘液的基本特征尚未报道。这项研究比较了使用常规热水提取(HWM)和超声波辅助提取(UAM)获得的这种粘液的物理化学和功能特性。HWM和UAM均不影响低于100μg/mL的小鼠皮肤成纤维细胞(NIH/3T3)的活力。UAM的产量更高,苯酚浓度,和体外抗氧化活性,但它的粘度和保水能力低于HWM。傅里叶变换红外光谱显示,透析后的HWM和UAM,命名为HWMD和UAMD,分别,在1730cm-1和1605cm-1处似乎具有主要的光谱差异,这意味着HWMD和UAMD之间的甲基化程度不同。与HWMD相比,低分子量多糖中UAMD增加。的确,各种提取物极大地改变了N.odorata心皮中天然粘液的基本特征。然而,糖分析表明,葡萄糖醛酸是HWMD和UAMD的主要成分。
    The cooked carpel of Nymphaea odorata has a large amount of transparent mucilage; however, the basic characteristics of this mucilage have not yet been reported. This study compared the physicochemical and functional properties of this mucilage obtained using conventional hot water extraction (HWM) and ultrasonic-assisted extraction (UAM). Neither HWM nor UAM affected the viability of mouse skin fibroblasts (NIH/3 T3) below 100 μg/mL. UAM had a higher yield production, phenol concentration, and in vitro antioxidant activity, but it had a lower viscosity and water-holding capacity than that of HWM. The Fourier transform infrared spectra revealed that the dialyzed HWM and UAM, named HWMD and UAMD, respectively, appeared to have major spectral differences at 1730 cm-1 and 1605 cm-1, implying that the degree of methylation was different between HWMD and UAMD. Compared to HWMD, UAMD in low-molecular weight polysaccharides increased. Indeed, the basic characteristics of native mucilage in the carpel of N. odorata were greatly changed by various extractions. Nevertheless, sugar analysis indicated that glucuronic acid was the main composition of HWMD and UAMD.
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  • 文章类型: Journal Article
    During the early ADME profiling the development of simple, interpretable and reliable in silico tools is very important. In this study, rule-based and QSPR approaches were investigated using a large Caco-2 permeability database. Three permeability classes were determined: high (H), moderate (M) and low (L). The main physicochemical properties related with permeability were ranked as follows: Polar Surface Area (PSA)>Lipophilicity (logP/logD)>Molecular Weight (MW)>number of Hydrogen Bond donors and acceptors>Ionization State>number of Rotatable Bonds>number of Rings. The best rule, based on the combination of PSA-MW-logD (3PRule), was able to identify the H, M and L classes with accuracy of 72.2, 72.9 and 70.6 %, respectively. Subsequently, a consensus system based on three voting binary classification trees was constructed. It accurately predicted 78.4/76.1/79.1 % of H/M/L compounds on training and 78.6/71.1/77.6 % on test set. Finally, the 3PRule and multiclassifier were validated with 23 drugs in a Caco-2 assay. The rule is very useful to improve assay design and prioritize the high absorption candidates. Meanwhile the QSPR model exhibits appropriate classification performance. Due to the simplicity, easy interpretation and accuracy, the 3PRule and consensus model developed here can be used in early ADME profiling.
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  • 文章类型: Journal Article
    Currently, products made with nanomaterials are used widely, especially in biology, bio-technologies, and medical areas. However, limited investigations on potential toxicities of nanomaterials are available. Hence, diverse and systemic toxicological data with new methods for nanomaterials are needed. In order to investigate the nanotoxicology of nanoparticles (NPs), the Research Team for Nano-Associated Safety Assessment (RT-NASA) was organized in three parts and launched. Each part focused on different contents of research directions: investigators in part I were responsible for the efficient management and international cooperation on nano-safety studies; investigators in part II performed the toxicity evaluations on target organs such as assessment of genotoxicity, immunotoxicity, or skin penetration; and investigators in part III evaluated the toxicokinetics of NPs with newly developed techniques for toxicokinetic analyses and methods for estimating nanotoxicity. The RT-NASA study was carried out in six steps: need assessment, physicochemical property, toxicity evaluation, toxicokinetics, peer review, and risk communication. During the need assessment step, consumer responses were analyzed based on sex, age, education level, and household income. Different sizes of zinc oxide and silica NPs were purchased and coated with citrate, L-serine, and L-arginine in order to modify surface charges (eight different NPs), and each of the NPs were characterized by various techniques, for example, zeta potentials, scanning electron microscopy, and transmission electron microscopy. Evaluation of the \"no observed adverse effect level\" and systemic toxicities of all NPs were performed by thorough evaluation steps and the toxicokinetics step, which included in vivo studies with zinc oxide and silica NPs. A peer review committee was organized to evaluate and verify the reliability of toxicity tests, and the risk communication step was also needed to convey the current findings to academia, industry, and consumers. Several limitations were encountered in the RT-NASA project, and they are discussed for consideration for improvements in future studies.
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