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An experimental study was undertaken to investigate the problem of the substantial variability in water content in unrotted sheep dung, which leads to a lack of universality and practicality in calibrating its discrete element simulation parameters. The stacking angle was used as the response value in these experiments. The objective of this study was to establish precise simulation parameters for the composting process. A model for water content-stacking angle was established using the cylinder-lifting technique, resulting in a correlation value of 0.997. Utilizing the Hertz–Mindlin with JKR bonding model, three EDEM particle models were developed, each with distinct particle sizes, based on the particle size distribution of sheep dung. The JKR surface energy was determined using the Plackett–Burman test, the steepest-climbing test, and the Box–Behnken test using a set of 10 parameters. A subsequent study was conducted on the JKR surface energy, rolling friction factor, and static friction factor utilizing the Plackett–Burman test and Box–Behnken test. A parameter model for stacking angle–discrete elements was developed that achieved a p-value below 0.0001 and a relative inaccuracy of 3.46% or less. The regression model for the water content–discrete element parameter was derived by combining the water content–stacking angle model with the stacking angle–discrete element parameter model. Validation of this model was conducted using both the pumping plate technique and the hopper approach, resulting in a relative error of 4.89% or less. The findings demonstrate that the specific characteristics of sheep manure may be accurately anticipated by considering its water content. This approach offers a valid and universally applicable way of predicting the specific characteristics of sheep dung in the simulation of composting equipment. [ABSTRACT FROM AUTHOR]

The Inner Mongolia Autonomous Region, known for its famous Mongolian horses, faces significant environmental challenges due to the large-scale rearing of these animals, which produces a substantial amount of manure. If not managed effectively, this manure can lead to severe environmental pollution. The aim of this study was to investigate whether a small-scale intelligent aeration and heating composting system is effective in treating Mongolian horse manure, with the objective of enhancing composting efficiency and resource utilization to support sustainable agricultural development in the region. The equipment was utilized to treat a compost mixture of Mongolian horse manure and corn stover, allowing for an analysis of the changes in key indicators throughout the composting process. The results demonstrated that the equipment maintained high temperatures for up to eight days during the composting process, effectively inactivating pathogens and promoting the efficient decomposition of organic matter. The system also successfully controlled humidity to 12.7% and maintained oxygen concentration within the optimal range. Post-composting analysis revealed that the final compost contained 2.3% nitrogen, 1.3% phosphorus, and 1.2% potassium, with a pH of 6.4 and conductivity of approximately 5.2 mS/cm. Additionally, the carbon-to-nitrogen ratio decreased significantly from 27.3 to 15.9, indicating substantial organic matter degradation. Seed germination tests showed germination rates of 80%, 86%, and 75% for corn, mung bean, and wheat, respectively, with a final seed germination index of 104%. This study concluded that the small aeration and heating composting equipment is highly effective in treating Mongolian horse manure, producing high-quality organic fertilizers that significantly enhance soil fertility and demonstrate considerable potential for supporting sustainable agricultural practices and improving environmental management in the Inner Mongolia Autonomous Region. [ABSTRACT FROM AUTHOR]

The Inner Mongolia Autonomous Region is a crucial area in China with a significant advantage in animal husbandry, particularly in cattle and sheep farming. However, the disposal of the large quantities of manure produced during farming has severely impacted the industry's healthy development. Proper treatment of the manure can convert it into organic fertilizer beneficial to farmland; otherwise, it will cause substantial environmental pollution. This study focuses on existing composting equipment and addresses the issues of cattle and sheep manure mixture ratios and compost maturity evaluation. Through experiments on the mixture of cattle and sheep manure, the optimal ratio for converting cattle and sheep manure into organic fertilizer was determined. Additionally, a fuzzy mathematical evaluation model was employed, along with experimental data, to establish a comprehensive evaluation system for aerobic compost maturity based on multiple indicators, revealing the variation patterns of maturity levels under different mixture ratios. The test results revealed that the composting equipment effectively controls the composting process, shortens the composting cycle, ensures the complete decomposition of organic matter, and meets national standards for livestock and poultry manure treatment. Regarding temperature and humidity, oxygen concentration, seed germination rate, pH value, electrical conductivity (EC), nitrogen, phosphorus, potassium content, and carbon-to-nitrogen ratio, the mixed compost of cattle and sheep manure in various ratios met the relevant standards for agricultural application. Various ratios of organic fertilizers containing cattle and sheep manure significantly promoted the growth of maize, wheat, and mung bean crops. Specifically, the compost decomposition cycle was shortest when sheep and cattle dung were mixed at a ratio of 2:1, while it was longest for all cattle dung. Finally, a fuzzy mathematical comprehensive evaluation model was established by selecting four indicators: water content, carbon-to-nitrogen ratio, apparent score, and germination index. The study demonstrates that the equipment and method offer significant advantages in efficiently treating cattle and sheep manure and producing organic fertilizer, thereby providing strong support for the sustainable development of animal husbandry. [ABSTRACT FROM AUTHOR]

With the installation of rubber isolation bearings in the upper and lower ground layers, an isolated step-terrace structure was created. Considering the ultimate bearing capacity of the rubber bearing under tension as the critical condition, a comprehensive framework was established to evaluate the overturning failure mechanisms present in isolated step-terrace structures. The bound of nominal aspect ratio was identified as the principal control index within this framework, which incorporates critical parameters such as height ratio (α), width ratio (β), vertical tensile stiffness to compressive stiffness ratio (γ), seismic coefficient (k), and nominal vertical compressive stress (σ0) to provide a thorough analysis of the structural responses and potential failure scenarios. In order to further investigate this matter, a scaled model of an isolated step-terrace concrete frame structure featuring two dropped layers and a single span within an 8° seismic fortification zone was meticulously crafted at a 1:10 similarity ratio. Subsequently, a series of shaking table tests were conducted to analyze the structural response under seismic excitation. The findings indicate that: utilizing the bound of nominal aspect ratio as a metric to gauge the anti-overturning capacity of isolated step-terrace structures is a justified approach. In instances where the height ratio remains constant, the bound of nominal aspect ratio for both positive and negative overturning trended upward with an increase in the width ratio. Notably, the bound of nominal aspect ratio for positive overturning consistently registered lower values compared to that of the negative overturning, underscoring the heightened susceptibility of step-terrace structures to positive overturning. Moreover, in scenarios characterized by higher height and width ratios, the structural integrity remained unscathed by any overturning effects arising from insufficient tensile strength in rubber bearings. Furthermore, the bound of nominal aspect ratio exhibited an ascending trend as the seismic coefficient, nominal vertical compressive stress, and vertical tensile stiffness to compressive stiffness ratio decreased. The outcomes derived from the shaking table test not only confirm the impressive seismic performance of the structure, but also, by closely examining the instantaneous stress variations within the upper and lower isolation layers of the model, substantiate the existence of a positive overturning hazard in scenarios marked by higher seismic coefficients (k). This observation aligns seamlessly with the theoretical projections, thereby substantiating the efficacy of the structural overturning failure theory through direct empirical verification. [ABSTRACT FROM AUTHOR]

This study specifically focuses on the damping efficiency of a damped structure with additional viscous dampers. A two-layer steel frame structure with eight sets of viscous dampers is used to conduct a series of seismic simulation shaking table tests, including a non-damped structure without dampers and two damped structures with dampers placed at 1/2 and 1/6 of the beam span, respectively. By conducting these tests, the energy dissipation, force, and displacement of the damper, as well as the parameters of the structure such as floor displacement and acceleration, are obtained. The main damping efficiency indicators of the damped structure are calculated, including the additional damping ratio, inter-story displacement utilization rate, as well as the reduction rate of the vertex displacement and the base shear relative to the non-damped structure. The study shows that the viscous dampers exhibit full hysteresis loops and a strong energy dissipation capacity in the structure. The seismic response of the vertex displacement and base shear in the damped structure is significantly smaller than that in the non-damped structure. Under different seismic levels, including frequent earthquakes, occasional earthquakes, and rare earthquakes, the damping effect of the dampers placed at 1/2 of the beam span is significantly better than that placed at 1/6 of the beam span. For example, the additional damping ratio for the X-direction artificial wave REN is 19% and 11%, 20% and 13%, and 13% and 11%, respectively. The patterns for inter-story displacement utilization ratio, reduction rate of the vertex displacement, and reduction rate of the base shear are similar. The research findings strongly indicate that the damped structure with additional viscous dampers exhibits excellent damping efficiency. In future damping design, designers need to fully consider the placement of viscous dampers within the beam span. [ABSTRACT FROM AUTHOR]

When subjected to seismic activity, tall isolated buildings with a high aspect ratio are susceptible to overturning as a result of the failure of rubber isolation bearings under tension. In order to address this issue, a guided-rail tension device (GR) has been developed to enhance the tensile strength of rubber bearings. Furthermore, a novel guided-rail isolation rubber bearing (GR&RB) has been proposed as a potential solution. Quasi-static tests have been conducted to investigate the mechanical properties of the GR, as well as the GR&LNR600 and LNR600. Additionally, numerical finite element analysis has been employed to study the seismic response of the GR&RB under El Centro seismic action in a high-rise building with an aspect ratio of approximately 4. The experimental results suggest that the inclusion of GRs has a limited effect on the horizontal mechanical attributes of rubber isolation bearings. Nevertheless, it simultaneously enhances their tensile strength, demonstrating a significant augmentation of 4.23 times. Moreover, the mechanical behavior of the GR aligns with the Hook model. The numerical analysis suggests that the utilization of GR&RB can mitigate the tensile stress levels of rubber isolators. Furthermore, it is recommended to augment the elastic tensile stiffness of the GR while reducing the open value to enhance the tensile efficiency, with the potential to attain up to 75% efficiency in tensile performance. [ABSTRACT FROM AUTHOR]

The traditional social force model (SFM) in crowd simulation experiences difficulty coping with the complexity of the crowd, limited by singular physical formulas and parameters. Recent attempts to combine deep learning with these models focus more on simulating specific states of crowds. This paper introduces an advanced deep social force model, influenced by crowd states. It utilizes deep neural networks to accurately fit crowd trajectory features, enhancing behavior simulation capabilities. Geometrical constraints within the model provide control over varied crowd behaviors, adjustable to simulate different crowd types. Before training, we use the SFM to refine behaviors in real trajectories with excessively small distances, aiming to enhance the general applicability of the model. Comparative experiments affirm the effectiveness of the model, showing comparable performance to both classic physical models and modern learning-based hybrid models in pedestrian simulations, with reduced collisions. In addition, the model has a certain ability to simulate crowds with high density and diverse behaviors. [ABSTRACT FROM AUTHOR]

The revolutionary progress in cancer immunotherapy, particularly the advent of immune checkpoint inhibitors, marks a significant milestone in the fight against malignancies. However, the majority of clinically employed immune checkpoint inhibitors are monoclonal antibodies (mAbs) with several limitations, such as poor oral bioavailability and immune-related adverse effects (irAEs). Another major limitation is the restriction of the efficacy of mAbs to a subset of cancer patients, which triggered extensive research efforts to identify alternative approaches in targeting immune checkpoints aiming to overcome the restricted efficacy of mAbs. This comprehensive review aims to explore the cutting-edge developments in targeting immune checkpoints, focusing on both small molecule- and peptide-based approaches. By delving into drug discovery platforms, we provide insights into the diverse strategies employed to identify and optimize small molecules and peptides as inhibitors of immune checkpoints. In addition, we discuss recent advances in nanomaterials as drug carriers, providing a basis for the development of small molecule- and peptide-based platforms for cancer immunotherapy. Ongoing research focused on the discovery of small molecules and peptide-inspired agents targeting immune checkpoints paves the way for developing orally bioavailable agents as the next-generation cancer immunotherapies. [ABSTRACT FROM AUTHOR]

To reveal the dynamic characteristics of asphalt core embankment dams (ACEDs), we carried out a dynamic triaxial experiment on hydraulic asphalt concrete (HAC) under different temperatures (T = 4 °C, 10 °C, 16 °C, and 22 °C) and stress states (Kc = 1.0, 1.2, 1.4, and 1.6; σ3 = 0.5, 0.6, 0.7, and 0.8 MPa). The results indicate that HAC's maximum dynamic elastic modulus increased with decreasing temperature, increasing principal stress ratio, and increasing confining pressure. However, the damping ratio showed the opposite trend. Moreover, in order to study the deformation capacity of HAC, 300 cyclic loads were applied to some specimens. At a temperature of 22 °C, the specimens had a tendency to deform axially, but not significantly. With a decrease in temperature, the axial deformation tendency of the specimen gradually weakened or even disappeared. However, a small number of cracks appeared in the aggregate and between the asphalt and the aggregate of the specimen. In order to quantify the dependence of dynamic parameters on temperature, the temperature influence factor of the maximum dynamic elastic modulus and the temperature sensing factor of the damping ratio were defined. The variation in the temperature influence factor of the maximum dynamic elastic modulus with temperature can be described by a logistic function. The temperature sensing factor of the damping ratio increased with an increasing principal stress ratio and peripheral pressure. Finally, maximum dynamic elastic modulus and damping ratio computational models for the interaction of temperatures and stress states were developed using the normalization method. Upon comparison, the dynamic parameters were observed to be very close to those listed in the literature, which verifies the applicability of the computational models of the maximum dynamic elastic modulus and damping ratio. [ABSTRACT FROM AUTHOR]

To develop monoammonium phosphate (MAP) as a novel acid source for durable intumescent fire retardants (IFR), MAP microcapsules (MCMAPs) containing MAP as the internal core and melamine-formaldehyde (MF) as the external shell were prepared by in situ polymerization in this study. The influences of synthesis conditions (including reaction temperature, polymerization time, and reaction pH value) on the properties of obtained MCMAPs (MAP content, yield, morphologies, and thermal properties) were then investigated systematically. The morphologies, chemical structures, and thermal properties were characterized by optical microscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), Fourier transform infrared (FTIR) spectroscopy, and thermogravimetry analyzer (TGA). The results show that MAP was well encapsulated by MF resin. No microcapsules are obtained at <55 °C or with polymerization times <1 h. Optimal preparation conditions of reaction temperature, polymerization time, and reaction pH value are 75 °C, 3 h, and 5.5, respectively. Those results provide process reference and theoretical basis for preparing MCMAPs and could promote the application of MAP microcapsules in wood flame-retardant materials. [ABSTRACT FROM AUTHOR]

The dry-wet cycle is an important factor that causes slope instability and foundation settlement in loess regions. In order to study the effects of the dry-wet cycle on the structure and shear strength of loess, isotropic compression tests and triaxial shear tests were carried out on loess with different numbers of dry-wet cycles. The results show that the dry-wet cycles mainly reduce the cohesion of loess, and the most obvious decline is after the first cycle; however, they have no effect on the angle of internal friction of loess. The structural yield strength and structural parameters of loess can represent the structure of loess well, which gradually decrease with the increase in the number dry-wet cycles and water content. The initial yield surface is approximately an ellipse, which gradually shrinks with the increase in water content and dry-wet cycles. The structure and cohesion of loess have similar changes, and there is an obvious exponential function relationship between them. [ABSTRACT FROM AUTHOR]

Long-term relief of indoor volatile pollution has become a competitive issue worldwide in both visible and dark environments. A novel self-luminous wood coating with carbon dots (CDs)/titanium dioxide (TiO2) nanomaterial coated SrAl2O4: Eu2+, Dy3+ (CDs/TiO2@SAO) composite was prepared for the long-term degradation of formaldehyde through a simple sol-gel method. The microstructure, chemical composition, ultraviolet-visible (UV-vis) spectra, and long-lasting fluorescence of the CDs/TiO2@SAO photocatalyst were analyzed to illustrate the mechanism for degrading formaldehyde. The obtained CDs with a particle size of ~2–7 nm have a good graphite structure and presented good absorption in visible light. In addition, owing to the synergistic effect of the CDs/TiO2 nanomaterial coating layer and the long-afterglow luminescence of the SAO phosphor, the CDs/TiO2@SAO composite can absorb a part of the visible light for photocatalytic degradation and store luminous energy efficiently at daytime so as to give out visible luminescence continuously for a few hours in the darkness. Furthermore, the functional wood coatings with CDs/TiO2@SAO composite presented continuous and efficient photocatalytic activity in the presence and absence of light exposure. The current research could provide a new strategy for designing an efficient photocatalyst for degrading formaldehyde pollution in the daytime with a visible light supply and in an indoor dark environment without an external light source. [ABSTRACT FROM AUTHOR]

Slate with inherently transverse isotropy is abundant in metamorphic rock, in buildings, and in geotechnical engineering worldwide; the tensile and shear fracture behavior of layered slate is vital to know for engineering applications. In this paper, the Brazilian and semi-circular bend (SCB) tests of layered slate were performed. The fracture characteristics of the slate were investigated by numerical simulations developed by the hybrid finite and cohesive element method (FCEM). Results showed that the measured experimental tensile strength, and mode I fracture toughness of layered slate all showed a typical V-type trend as the bedding angle increased from 0° to 90°, and with divider type. The developed empirical relationship between tensile fracture toughness and tensile strength KIC = 0.094σt + 0.036 fitted experimentally and strongly correlated. The mechanical response and fracture patterns predicted by FCEM agreed well with those of the laboratory experiments. Moreover, the shear fracture behavior and mode II fracture toughness of the layered slate were explored by systematic numerical simulations. Research results provide potential insights for further prediction and improvement of the complex fracture behavior of anisotropic rock masses for rock engineering. [ABSTRACT FROM AUTHOR]

The gut microbiota and its derived metabolites greatly impact the host immune system, both innate and adaptive responses. Gut dysbiosis and altered levels of microbiota-derived metabolites have been described in several immune-related and immune-mediated diseases such as intestinal bowel disease, multiple sclerosis, or colorectal cancer. Gut microbial-derived metabolites are synthesized from dietary compounds ingested by the host or host-produced metabolites, and additionally, some bacterial products can be synthesized de novo. In this review, we focus on the two first metabolites families including short-chain fatty acids, indole metabolites, polyamines, choline-derived compounds, and secondary bile acids. They all have been described as immunoregulatory molecules that specifically affect the adaptive immune system and T helper 17 and regulatory T cells. We discuss the mechanisms of action and the consequences in health and diseases related to these gut microbial-derived metabolites. Finally, we propose that the exogenous administration of these molecules or other compounds that bind to their immunoregulatory receptors in a homologous manner could be considered therapeutic approaches. [ABSTRACT FROM AUTHOR]

Objective: To explore the characteristics of metabolites in Shenheling (SHL) fermented by Lactobacillus fermentum. Methods: In this study, ultrahigh-performance liquid chromatography-quadrupole electrostatic field orbit trap mass spectrometry (UHPLC-QE-MS) was used to qualitatively, quantitatively, and differentially analyze the metabolites of SHL before and after fermentation. Results: A total of 102 significant differential metabolites in nine categories were analyzed before and after fermentation. It mainly includes 29 terpenoids, 17 alkaloids, 14 organic acids and derivatives, 10 flavonoids, 9 phenylpropanoids, 6 phenols, 3 aromaticity, and 3 amino acid derivatives. Further screening found that the content of most active substances, such as alkaloids, organic acids, and flavonoids, increased significantly. These metabolites play an important role in improving the taste and efficacy of SHL. After fermentation, the contents of differential metabolites, such as panaquinquecol 2, ginsenoside Rh3, ginsenoside Rg3, dehydronuciferin, nicotinic acid, 5-hydroxytryptophan, azelaic acid, dihydrokaempferol, and chrysin, were increased, which increased the effects of antioxidation, anti-obesity, hypoglycemic, antibacterial, and improved immunity compared with those before fermentation. KEGG pathway analysis identified 10 metabolic pathways. Isoquinoline alkaloid biosynthesis, vitamin B6 metabolism, beta-alanine metabolism, nicotinate, and nicotinamide metabolism, purine metabolism, pantothenate and CoA biosynthesis, glyoxylate and dicarboxylate metabolism, tyrosine metabolism, citrate cycle (TCA cycle), phenylpropanoid biosynthesis, etc. Conclusions: Fermentation significantly changed the metabolites in SHL and played an important role in improving its taste, aroma quality, antioxidant, anti-obesity, and other health care functional components. [ABSTRACT FROM AUTHOR]

Intestinal colonization is beneficial to the role of probiotics, and prebiotics can promote the adhesion and colonization of probiotics in the intestine. This study optimized the combination of complex prebiotics that could improve the growth ability and adhesion ability of Limosilactobacillus fermentum (L. fermentum) DALI02 to Caco-2 cells in vitro and determined the effect of its colonization quantity and colonization time in the immunocompromised rat model. The results showed that all five prebiotics (fructo-oligosaccharides (FOS), galacto-oligosaccharides (GOS), inulin, stachyose, and xylo-oligosaccharides (XOS)) significantly promoted the growth and adhesion of L. fermentum DALI02. It was found that 0.5% (w/w) inulin had the best growth promotion effect, and 0.5% FOS had the strongest adhesion promotion (the adhesion rate was increase by 1.75 times). In addition, 0.05% FOS, 0.20% GOS, 0.30% inulin, 0.20% stachyose, and 0.30% XOS could significantly improve the adhesion rate of L. fermentum DALI02 from 1.72% to 3.98%. After 1 w of intervention, the quantity of colonization in the fermented broth with prebiotics group was significantly higher than that in the fermented broth group. The intervention time was extended from 1 d to 4 w, and the amount of colonization of L. fermentum DALI02 in the fermented broth with prebiotics group increased significantly from 4.32 lgcopies/g to 5.12 lgcopies/g. After the intervention, the serum levels of lipopolysaccharide (LPS) and D-lactic acid in rats were significantly reduced, and the most significant was in the fermented broth with prebiotics group, with LPS and D-lactic acid levels of 74.11 pg/mL and 40.33 μmol/L, respectively. Complex prebiotics can promote the growth and adhesion of L. fermentum DALI02 and significantly increase the quantity of colonization and residence time of the strain in the intestine, which helps the restoration of intestinal barrier function and other probiotic effects. [ABSTRACT FROM AUTHOR]

To explore the modulating effect of Limosilactobacillus fermentum (L. fermentum) grx08 on anti-oxidative stress in the liver, heart, and kidney of high-fat diet in rats, a low-fat diet as a control and a high-fat diet was used to induce oxidative stress injury in rats. L. fermentum grx08 and its heat-inactivated bacteria were used to intervene. The results showed that the high-fat diet had caused oxidative stress injury in the liver, heart, and kidney of rats. L. fermentum grx08 significantly reduced the serum levels of liver, heart, and kidney injury markers (ALT, AST, LDH, CK-MB, UA, and Crea), while restoring the balance of lipid metabolism in the liver. It also enhanced the activity of antioxidant enzymes such as GSH-Px in the liver, heart, and kidney, scavenging NO radicals and reducing the content of MDA, a product of lipid peroxidation, which can regulate the anti-oxidative stress capacity of the liver, heart, and kidney to varying degrees. Among them, L. fermentum grx08 showed better modulating effect on kidney anti-oxidative stress, followed by liver, and the weakest modulating effect on heart. At the same time, L. fermentum grx08 heat-inactivated bacteria also had a partial modulatory effect as well as a similar effect profile to that of live bacteria. [ABSTRACT FROM AUTHOR]

This paper describes a study on the interaction between joint fissures in a nonpersistent jointed rock mass by introducing a self-consistent methodology, amending the traditional method of self-consistency by increasing the number of joints one by one, and deducing a new compound mesoscale and macroscale constitutive damage model based on the Betti energy reciprocity theorem. By analyzing the Mohr–Coulomb failure criterion and generalized von Mises yield criterion and their impact on the calculation result of macroscopic damage, the generalized von Mises criterion is proven to be more appropriate, and it is, thus, chosen for this compound damage constitutive model. Comparing the theoretical calculation and laboratory results of the compound damage model with the existing theoretical calculation results indicates the following: 1. The compound damage model in this paper provides a better fit of the stress–strain curves from the laboratory tests. 2. The theoretical calculative results for the compound damage model in this paper are consistent with the experimental results; that is, the peak load decreases as the connectivity rate increases. 3. For different joint angles and connectivity rates, the overall absolute deviations and relative deviations of the peak stress from the theoretical calculations and the laboratory tests are less than those from the theoretical calculations provided in the original literature. The theoretical calculations of the compound damage model in this paper are more aligned with the experimental results, verifying its correctness and rationality. [ABSTRACT FROM AUTHOR]

Flexible 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO)-oxidized nanofibrillated cellulose (ONFC) films with long afterglow luminescence containing modified SrAl2O4: Eu2+, Dy3+ (SAOED) phosphors were fabricated by a template method. Tetraethyl orthosilicate (TEOS) and (3-aminopropyl) trimethoxy-silane (APTMS) were employed cooperatively to improve the water resistance and compatibility of the SAOED particles in the ONFC suspension. The structure and morphology after modification evidenced the formation of a superior SiO2 layer and coarse amino-compounds on the surface of the phosphors. Homogeneous dispersions containing ONFC and the modified phosphors were prepared and the interface of composite films containing the amino-modified particles showed a more closely packed structure and had less voids at the interface between the cellulose and luminescent particles than that of silica-modified phosphors. The emission spectra for luminescent films showed a slight blue shift (3.2 nm) at around 512 nm. Such flexible films with good luminescence, thermal resistance, and mechanical properties can find applications in fields like luminous flexible equipment, night indication, and portable logo or labels. [ABSTRACT FROM AUTHOR]

A surface plasmon resonance (SPR) sensor based on a side-polished single mode fiber coated with polyvinyl alcohol (PVA) is demonstrated for relative humidity (RH) sensing. The SPR sensor exhibits a resonant dip in the transmission spectrum in ambient air after PVA film coating, and the resonant wavelength shifts to longer wavelengths as the thickness of the PVA film increases. When RH changes, the resonant dip of the sensor with different film-thicknesses exhibits interesting characteristics for optical spectrum evolution. For sensors with initial wavelengths between 550 nm and 750 nm, the resonant dip shifts to longer wavelengths with increasing RH. The averaged sensitivity increases firstly and then drops, and shows a maximal sensitivity of 1.01 nm/RH%. Once the initial wavelength of the SPR sensor exceeds 850 nm, an inflection point of the resonant wavelength shift can be observed with RH increasing, and the resonant dip shifts to shorter wavelengths for RH values exceeding this point, and sensitivity as high as &minus;4.97 nm/RH% can be obtained in the experiment. The sensor is expected to have potential applications in highly sensitive and cost effective humidity sensing.