Miracle-dz/UniFAR-FTUs huggingface dataset:
Carbon Nanotubes Composites: Processing, Grafting and Mechanical and Thermal Properties

Carbon nanotubes represent one of the most important materials in nanoscience and nanotechnology today. The exceptional properties that these materials possess open new fields in science and engineering. Additionally, the chemistryassociated to these materi- als starts to play an important role, inasmuch, new moieties insert by different chemical routes, inside and outside of carbon nanotubes surfaces, have shown able to modify their structure and properties. To this date, new properties have been found in chemically-modified nanotubes and diverse potential applications are suggested for these materials. One of the most frequent applications for these carbon ma- terials is their inclusion as reinforcement in polymer matrices, due to the amazing structural, mechanical, electrical, chemical and thermal properties that carbon nanotubes possess, suggesting that these materials are ideal to produce new polymer nanocomposites. In this con- text, carbon nanotube nanocomposites have been developed by numerous research groups around the world aiming to produce new novel strong and light composite materials. Also, electrical conductivity and thermal properties have been studied for this kind of nanocompo- sites. However, new challenges to create a new age of multifunctional composite materials with these nanometric forms arise and, there- fore, the study of new properties in these nanocomposites has increased significantly in the last few years. In this review we discuss a range of methods to properly utilize nanotubes in poymer-based composites, from the solubility behavior of carbon nanotubes, the proc- essing methods to develop carbon nanotube polymer composites, interactions produced between carbon nanotubes and polymer grafted, to the most recent results on the mechanical and thermal properties of carbon nanotubes polymer composites, synthesized with different types of carbon nanotubes. In addition, we discuss the effect of different chemical modifications on nanotubes, with special focus on those developed to improve the compatibility between these nanostructures and engineering polymers, as well as their effect on the final composites properties. The significance of understanding, enhancing and controlling the behavior at the interface between nanotubes and polymer matrices towards the development of novel multifunctional applications with these composites, is also discussed in detail.
The Study on the Mineral Phase Transformations and Thermodynamics of Laterite Ores Calcination

In this paper, mineralogical phase transformations of Indonesia nickel laterite ores are studied during calcinations, the thermodynamics of process are also investigated. Different factors that affect the reduction of the laterite ores are tested and analyzed by Differential Scanning Calorimeter (DSC), X-ray Diffraction (XRD), Brunauer Emmett Teller (BET) and Scanning Electron Microscope (SEM). The results show that during calcination process, goethite is dehydrolyzed by removing structural water at about 300°C, which then transforms to hematite, and serpentine decomposes at around 600~700°C, leading to formulate olivine if agglomerating at higher temperature. By thermodynamics calculation, the goethite dehydration temperature is under 100°C, and about 200°C for serpentine decomposition. It might be the inclusions in ore which make laterite become hard to decompose.
The uncertainty principle of cross-validation

Data miners have often to deal with data sets of limited size due to economic, timing and other constraints. Usually their task is twofold: to induce the most accurate model from a given dataset and to estimate the model's accuracy on future (unseen) examples. Cross-validation is the most common approach to estimating the true accuracy of a given model and it is based on splitting the available sample between a training set and a validation set. The practical experience shows that any cross-validation method suffers from either an optimistic or a pessimistic bias in some domains. In this paper, we present a series of large-scale experiments on artificial and real-world datasets, where we study the relationship between the model's true accuracy and its cross-validation estimator. Two stable classification algorithms (ID3 and info-fuzzy network) are used for inducing each model. The results of our experiments have a striking resemblance to the well-known Heisenberg Uncertainty Principle: the more accurate is a model induced from a small amount of real-world data, the less reliable are the values of simultaneously measured cross-validation estimates. We suggest calling this phenomenon "the uncertainty principle of cross-validation".
Hopf bifurcation of spike solutions for the shadow Gierer–Meinhardt model

In the limit of small activator diffusivity, the stability of a one-spike solution to the shadow Gierer–Meinhardt activator-inhibitor system is studied for various ranges of the reaction-time constant $\tau$ associated with the inhibitor field dynamics. By analyzing the spectrum of the eigenvalue problem associated with the linearization around a one-spike solution, it is proved, for a certain parameter regime, that a complex conjugate pair of eigenvalues crosses into the unstable right half-plane $Re(\lambda) > 0$ as $\tau$ increases past a critical value $\tau_0$. For this parameter regime, it is proved that there are exactly two eigenvalues in the right half-plane when $\tau > \tau_0$ and none when $0 \leq \tau < \tau_0$. It is shown numerically that this critical value of $\tau$ represents the onset of an oscillatory instability in the height of the spike. For other parameter regimes, a similar Hopf bifurcation is confirmed numerically. Full numerical solutions to the shadow problem are computed for a spike that is initially centred at the origin of a radially symmetric domain. Different types of large-scale oscillatory motions for the height of a spike are observed numerically for values of $\tau$ well beyond $\tau_0$.
Improvement of critical current density in MgB2 by optimizing process parameters and chemical doping

The discovery of superconductivity in MgB 2 in January 2001 has triggered enormous interest around the world. MgB 2 has evolved as a promising superconductor for the next generation of superconductor applications, due to not only its higher critical temperature (T c = 39 K), low material cost, and good weak-link tolerance, but also its rich multiple-band structure. However, several issues exist that urgently need to be solved, such as its low upper critical field (H c2 ) and rapid decrease in critical current density (J c ) under magnetic field compared to Nb-based superconductors. High J c (H) performance is crucial for the application of this material in the so-called “strong electrical application” field. Therefore, the objective of this thesis is to increase J c of bulk polycrystalline MgB 2 via studying the influence of the boron precursor powder and the nominal Mg/B mixing ratio and efforts to further enhance J c by doping with two types of sources: carbon sources (such as SiC and sucrose) and oxygen sources (such as TiO 2 /SiO 2 and processing atmospheres with different oxygen content). powder very important to critical current density 2 . In terms of influence properties , J c values 2 made from 2 sample
Performance Evaluation of Membership Functions on Fuzzy Logic Controlled AC Voltage Controller for Speed Control of Induction Motor Drive

objective of this paper is to investigate the effect of membership functions in the fuzzy control (FC) of an ac voltage controller for speed control of induction motor drive. A Sugeno type FC for closed loop control of induction motor drive fed by ac voltage controller is designed and considered for evaluation. The controller is used to change the firing angle of the ac volage controller and thereby, the voltage fed to stator of induction motor to regulate the speed. Sugeno type FC is selected for evaluation, as it is easy to implement in simulation. The membership functions selected for evaluation are triangular, trapezoidal, Gaussian and bell shaped functions. The different membership function evaluation is done considering seven linguistic sets for error and change in error. The simulation model of different membership functions in the fuzzy control (FC) of an ac voltage controller for speed control of induction motor drive is implemented in Matlab/simulink The results of the simulated performances are compared. The triangular membership function shows better performance compared to other membership functions.
Monte Carlo Algorithms for the Partition Function and Information Rates of Two-Dimensional Channels

The paper proposes Monte Carlo algorithms for the computation of the information rate of 2-D source/channel models. The focus of the paper is on binary-input channels with constraints on the allowed input configurations. The problem of numerically computing the information rate, and even the noiseless capacity, of such channels has so far remained largely unsolved. Both problems can be reduced to computing a Monte Carlo estimate of a partition function. The proposed algorithms use tree-based Gibbs sampling and multilayer (multitemperature) importance sampling. The viability of the proposed algorithms is demonstrated by simulation results.
Enhanced HIV-1 replication by chemokines constitutively expressed in secondary lymphoid tissues.

Persistent infection of human immunodeficiency virus (HIV) takes place in the secondary lymphoid tissues even during clinically latent stages. The CC chemokines secondary lymphoid tissue chemokine (SLC) and EBI1-ligand chemokine (ELC) are constitutively expressed in the secondary lymphoid tissues. They share CCR7 expressed on lymphocytes and mature dendritic cells and play key roles in the trafficking of these types of cells into the secondary lymphoid tissues. Here we report that growth of both X4 and R5 strains of HIV-1 in activated peripheral blood T cells was enhanced by SLC. The enhancing effect of SLC was abrogated by pretreatment of cells with pertussis toxin, indicating the involvement of signaling via a receptor coupled with a Galphai class of G-protein. Furthermore, SLC was found to enhance the promoter activity of HIV-1 LTR. These results suggest that signaling via CCR7 has a strong positive effect on HIV growth. Thus, SLC and ELC may contribute to persistent infection of HIV in the secondary lymphoid tissues by promoting viral replication in activated T cells.
Characterization of the algC Gene Expression Pattern in the Multidrug Resistant Acinetobacter baumannii AIIMS 7 and Correlation with Biofilm Development on Abiotic Surface

Relative quantification of algC gene expression was evaluated in the multidrug resistant strain Acinetobacter baumannii AIIMS 7 biofilm (3 to 96 h, on polystyrene surface) compared to the planktonic counterparts. Comparison revealed differential algC expression pattern with maximum 81.59-fold increase in biofilm cells versus 3.24-fold in planktonic cells (P < 0.05). Expression levels strongly correlated with specific biofilm stages (scale of 3 to 96 h), coinciding maximum at initial surface attachment stage (9 h) and biofilm maturation stage (48 h). Cloning, heterologous expression, and bioinformatics analyses indicated algC gene product as the bifunctional enzyme phosphomannomutase/phosphoglucomutase (PMM/PGM) of ∼53 kDa size, which augmented biofilms significantly in algC clones compared to controls (lacking algC gene), further localized by scanning electron microscopy. Moreover, molecular dynamics analysis on the three-dimensional structure of PMM/PGM (simulated up to 10 ns) revealed enzyme structure as stable and similar to that in P. aeruginosa (synthesis of alginate and lipopolysaccharide core) and involved in constitution of biofilm EPS (extracellular polymeric substances). Our observation on differential expression pattern of algC having strong correlation with important biofilm stages, scanning electron-microscopic evidence of biofilm augmentation taken together with predictive enzyme functions via molecular dynamic (MD) simulation, proposes a new basis of A. baumannii AIIMS 7 biofilm development on inanimate surfaces.
Power-Biased Technological Change and the Rise in Earnings Inequality

New information and communication technologies, we argue, have been ‘power- biased’: they have allowed firms to monitor low-skill workers more closely, thus reducing the power of these workers. An efficiency wage model shows that ‘power-biased technical change’ in this sense may generate rising wage inequality accompanied by an increase in both the effort and unemployment of low-skill workers. The skill-biased technological change hypothesis, on the other hand, others no explanation for the ob- served increase in effort.
Image super-resolution based on hybrid multiresolution analysis

In this paper, a novel image super-resolution scheme based on hybrid multiresolution analysis is proposed. Firstly, low resolution image is divided into components with different morphological features by morphological component analysis (MCA). Then super-resolution is performed for each component by the hybrid multiresolution analysis based on stationary wavelet transform (SWT) and nonsubsampled contourlet transform (NSCT). Experimental results on test benchmark images and license plate images validate the method's performance.
Studies on melt spinning. II. Steady‐state and transient solutions of fundamental equations compared with experimental results

In the part installment of the present paper, the authors formulated the dynamics of melt spinning by introducing a set of fundamental equations that consist of the equations of heat, force, and material balances. Some steady-state solutions were also given. Additional steady-state solutions corresponding to many different spinning conditions for polyester and polypropylene filament yarns consistently show good agreement with experimental results. These steady-state solutions that give filament cross-section A (x) and filament temperature t(x) as functions of position x are correlated with yarn qualities: yarn density and birefringence, crystallinity and molecular orientation, are correlated respectively with the speed of Polymer cooling at 100°C. and the maximum tensile stress (F/A)w acting on the filament. A transient solution of the fundamental equations computed on an IBM 1401 machine shows that the filament cross-section A at the take-up roll forms a large transient peak after a stepwise increase in the speed vy of cooling air. This agrees with experiments fairly well. The fundamental equations, therefore, clarify the dynamic relations between cooling air speed and yarn weight variations.
Compaction Delay Effects on Properties of Lime-Treated Soil

A statistical study of the effects of compaction delays on properties of lime-stabilized lateritic soil was conducted using two-way analysis of variance and multiple regression analysis. The reductions in mavimum dry density (MDD) and optimum moisture content (OMC) associated with compaction delays are statistically significant at the 5% level, regardless of the compactive effort employed (i.e., standard Proctor or West African Standard). The effects of compaction delays on unconfined compressive stength (UCS) are statistically significant for different compactions, lime contents, and curing. Compaction delay effects on California bearing ratio (CBR) of soil–lime mixtures are statistically significant. The t -statistics from regression analysis show that compaction delays significantly influence the measured values of MDD, OMC, UCS, and CBR. It is believed that the findings of this study will be helpful in controlling the compaction delay for lime-treated soils.
Synthesis and mechanical properties of Al8B4C7

Aluminum boron carbide (Al8B4C7) was synthesized by heating a mixed powder consisting of Al:B4C:C = 8:1:6 (molar ratio) at 1600°C for 1 h. The synthesized Al8B4C7 powder was ball milled for 24 h with alumina balls to prepare an Al8B4C7 powder with under 40 μm diameter. The fine Al8B4C7 powder was then put into a carbon die, pressed, and sintered using PECS at 1650°C for 10 min under an applied pressure of 60 MPa, resulting in an Al8B4C7 body with a relative density of 99.6%. The bending strength, Vickers hardness, and fracture toughness of the dense Al8B4C7 body were 500 MPa, 15.2 GPa and 2.3 MPa·m1/2, respectively. The bending strength of the dense Al8B4C7 body increased during heating to 510 MPa at 1000°C, but decreased to 440 MPa at 1200°C.
Characterization of lead-free solders and under bump metallurgies for flip-chip package

A variety of Pb-free solders and under bump metallurgies (UBMs) was investigated for flip chip packaging applications. The result shows that the Sn-0.7Cu eutectic alloy has the best fatigue life and it possess the most desirable failure mechanism in both thermal and isothermal mechanical tests regardless of UBM type. Although the electroless Ni-P UBM has a much slower reaction rate with solders than the Cu UBM, room temperature mechanical fatigue is worse than on the Cu UBM when coupled with either Sn-3.8Ag-0.7Cu or Sn-3.5Ag solder. The Sn-37Pb solder consumes less Cu UBM than all other Pb-free solders during reflow. However, Sn-37Pb consumes more Cu after solid state annealing. Studies on aging, tensile, and shear mechanical properties show that the Sn-0.7Cu alloy is the most favorable Pb-free solder for flip chip applications.
Real-time Indirect Illumination with Clustered Visibility

Visibility computation is often the bottleneck when rendering indirect illumination. However, recent methods based on instant radiosity have demonstrated that accurate visibility is not required for indirect illumination. To exploit this insight, we cluster a large number of virtual point lights ‐ which represent the indirect illumination when using instant radiosity ‐ into a small number of virtual area lights. This allows us to compute visibility using recent real-time soft shadow algorithms. Such approximate and fractional from-area visibility is faster to compute and avoids banding when compared to exact binary from-point visibility. Our results show, that the perceptual error of this approximation is negligible and that we achieve real-time frame-rates for large and dynamic scenes.
Characteristic Analysis and Experimental Evaluation of Fluidic Muscle Cylinder

The fluidic muscle cylinder consists of an air bellows tube, flanges and lock nuts. Its features are softness of material and motion, simplicity of structure, low production cost and high power efficiency. Recently, unlike the pneumatic cylinder, the fluidic muscle cylinder without air leakage, stick slip, friction or seals was developed as a new concept actuator. It has characteristics such as light weight, low price, high response, durable design, long life, high power and high contraction. In this study, we carried out finite element modeling and analysis on the main design variables such as contraction ratio and force, and diameter increment of the fluidic muscle cylinder. On the basis of finite element analysis, the prototype fluidic muscle cylinder was fabricated and tested. Finally, we compared the test results with the finite element analysis.
Prostatic Acid Phosphatase Is Required for the Antinociceptive Effects of Thiamine and Benfotiamine

Thiamine (Vitamin B1) is an essential vitamin that must be obtained from the diet for proper neurological function. At higher doses, thiamine and benfotiamine (S-benzoylthiamine O-monophosphate, BT)–a phosphorylated derivative of thiamine–have antinociceptive effects in animals and humans, although how these compounds inhibit pain is unknown. Here, we found that Prostatic acid phosphatase (PAP, ACPP) can dephosphorylate BT in vitro, in dorsal root ganglia (DRG) neurons and in primary-afferent axon terminals in the dorsal spinal cord. The dephosphorylated product S-benzoylthiamine (S-BT) then decomposes to O-benzoylthiamine (O-BT) and to thiamine in a pH-dependent manner, independent of additional enzymes. This unique reaction mechanism reveals that BT only requires a phosphatase for conversion to thiamine. However, we found that the antinociceptive effects of BT, thiamine monophosphate (TMP) and thiamine–a compound that is not phosphorylated–were entirely dependent on PAP at the spinal level. Moreover, pharmacokinetic studies with wild-type and Pap−/− mice revealed that PAP is not required for the conversion of BT to thiamine in vivo. Taken together, our study highlights an obligatory role for PAP in the antinociceptive effects of thiamine and phosphorylated thiamine analogs, and suggests a novel phosphatase-independent function for PAP.
Effect of intranasal rosiglitazone on airway inflammation and remodeling in a murine model of chronic asthma

Background/Aims: Asthma is characterized by airway hyperresponsiveness, inflammation, and remodeling. Peroxisome proliferator-activated receptors have been reported to regulate inflammatory responses in many cells. In this study, we examined the effects of intranasal rosiglitazone on airway remodeling in a chronic asthma model. Methods: We developed a mouse model of airway remodeling, including smooth muscle thickening, in which ovalbumin (OVA)-sensitized mice were repeatedly exposed to intranasal OVA administration twice per week for 3 months. Mice were treated intranasally with rosiglitazone with or without an antagonist during OVA challenge. We determined airway inflammation and the degree of airway remodeling by smooth muscle actin area and collagen deposition. Results: Mice chronically exposed to OVA developed sustained eosinophilic airway inflammation, compared with control mice. Additionally, the mice developed features of airway remodeling, including thickening of the peribronchial smooth muscle layer. Administration of rosiglitazone intranasally inhibited the eosinophilic inflammation significantly, and, importantly, airway smooth muscle remodeling in mice chronically exposed to OVA. Expression of Toll-like receptor (TLR)-4 and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) was increased in the OVA group and decreased in the rosiglitazone group. Co-treatment with GW9660 (a rosiglitazone antagonist) and rosiglitazone increased the expression of TLR-4 and NF-κB. Conclusions: These results suggest that intranasal administration of rosiglitazone can prevent not only air way inf lammation but also air way remodeling associated with chronic allergen challenge. This beneficial effect is mediated by inhibition of TLR-4 and NF-κB pathways.