Review: the latest advances in biomedical applications of chitosan hydrogel as a powerful natural structure with eye-catching biological properties

Journal of Materials Science - Chitosan is one of the natural cationic polymers with unique properties such as non-toxicity, biodegradability, biocompatibility, environmentally friendly that has...     

Mining fleet management systems: a review of models and algorithms

The objective of this paper is to review and document the mine fleet management systems’ models and algorithms. The purpose is to understand the algorithms behind the fleet management systems and the proposed academic solutions in this area to identify any gaps in the current literature and to open up opportunities to establish research questions that need to be addressed in an integrated simulation and optimisation operational planning research framework. In this paper, we review industrial fleet management systems and the main academic algorithms behind such systems. The fleet management systems are divided into three subsequently related problems to review: shortest path, production optimisation and real-time dispatching. Finally, the limitations of current algorithms for fleet management systems are documented in terms of mining practice feasibility and optimality of the solution on large-scale problems. The results of this literature review enable us to evaluate the logical links between major components of an integrated simulation and optimisation operational planning framework with current theory of fleet management systems.     

高速数据转换器接口

数据转换器的复杂性随着采样频率及精度的提高而增加。高性能的数据转换器规格的设定必须遵循严格的输入条件,以实现器件预期性能的最大化。一个颇具挑战性的输入条件是:对ADC输入模拟信号进行测量、驱动和接口连接。本文将探讨一些对高速ADC进行有效接口连接的技术,从而使ADC实现性能最佳化。     

Mixed Micelles of Surface Active Ionic Liquid (SAIL)–Octylphenol Ethoxylate: A Novel Reaction Medium for Selective Oxidation of Toluene to Benzaldehyde

Ionic liquids have been found to be suitable alternatives to volatile organic solvents in chemical transformation. Through a proper choice of cations and anions, the properties of an ionic liquid can be tuned so that it resembles an amphiphile. Such specially designed molecules are known as surface-active ionic liquids (SAIL). Like conventional surfactants, SAIL also form aggregates in an aqueous medium. Studies show that the mixing of SAIL with conventional surfactants leads to synergistic micellization. However, very few reports are available on the application of such systems as reaction media. Present study focuses on the application of mixed micelles of 1-tetradecyl-3-methylimidazol-1-ium bromide, ([C₁₄mim]Br) with nonionic surfactant, Octylphenol ethoxylate with 10 moles of ethylene oxide (OPE-10). Enhanced solubilization and selective catalytic oxidation of toluene using hydrogen peroxide as an oxidant and tungstic acid as a catalyst have been studied in detail using this system.     

Gazing Geometries: Modes of Design Thinking in Pre-Modern Central Asia and Persian Architecture

The architecture of the pre-modern Islamic world broadly identifies itself with geometric design. In erecting buildings, architects-engineers of the Islamic world utilized distinct modes of geometric projections vital to the spatial conception of the building. These representations identify three modes of design drawings: plans, revetments/vertical surfaces, and reflected ceiling plans. This paper will discuss these modes of drawings and their unique role in relation to the architectural “design thinking” traditions. Much has been examined regarding two-dimensional Islamic geometric patterns (girih), but little exists in terms of a comprehensive framework investigating various modes of geometric drawings in relation to formal, spatial, and tectonic conceptions of the architectural space. This paper fills a critical gap in the literature about Islamic architecture and examines this topic through primary resources and original pamphlets.     

In situ, noninvasive characterization of superhydrophobic coatings

Light scattering was used to measure the time-dependent loss of air entrapped within a submerged microporous hydrophobic surface subjected to different environmental conditions. The loss of trapped air resulted in a measurable decrease in surface reflectivity and the kinetics of the process was determined in real time and compared to surface properties, such as porosity and morphology. The light-scattering results were compared with measurements of skin-friction drag, static contact angle, and contact-angle hysteresis. The in situ, noninvasive optical technique was shown to correlate well with the more conventional methods for quantifying surface hydrophobicity, such as flow slip and contact angle.     

Lichtenstein herniotomy

All standard methods of hernia repair involve suturing together tissues which are not normally in apposition. This violates the basic surgical principle that tissue must never be approximated under tension and accounts for an unacceptable number of failures. Total reinforcement of the inguinal floor with a sheet of suitable biomaterial and employment of a "tension-free" technique is a more effective approach. Since June 1984, 3250 primary inguinal hernias have been repaired at the Lichtenstein Hernia Institute by the open tension-free technique using Marlex mesh. All operations were performed under local anesthesia. Patients were discharged from the hospital within two or four hours after the operation. The patients were followed from one to 8 years by physician examination. The follow-up rate was 87%. There were four recurrences. The causes of recurrence and how to avoid them are discussed.     

Mass‐transfer enhancement in single drop extraction in the presence of magnetic nanoparticles and magnetic field

Magnetite nanoparticles with an average particle size of 28.8 nm were synthesized, coated with oleic acid, and characterized using various techniques such as DLS, FT‐IR, SEM, XRD, VSM, and UV‐Vis analysis. A nanofluid consisting of synthesized nanoparticles and 5 wt % acetic acid in toluene as the dispersed phase was prepared and used in the chemical test system, Toluene‐Acetic Acid‐Water, for the single drop extraction in the presence and absence of an external oscillating magnetic field. Influences of various operating and design parameters such as nanoparticle concentration, drop diameter, and the applied current and frequency on the overall mass‐transfer coefficients for the mass‐transfer direction from d→c were investigated carefully. The obtained results were used to propose a general correlation for the mass‐transfer enhancement. It was found that the maximum mass‐transfer enhancement compared with that obtained in the absence of nanoparticles and the oscillating magnetic field is about 259%. © 2016 American Institute of Chemical Engineers AIChE J, 62: 4466–4479, 2016     

Evaluation of most similar neighbour and random forest methods for imputing forest inventory variables using data from target and auxiliary stands

We report the results from modelling standing volume, above-ground biomass and stem count with the aim of exploring the potential of two non-parametric approaches to estimate forest attributes. The models were built based on spectral and 3D information extracted from airborne optical and laser scanner data. The survey was completed across two geographically adjacent temperate forest sites in southwestern Germany, using spatially and temporally comparable remote-sensing data collected by similar instruments. Samples from the auxiliary reference stands (called off-site samples) were combined with random, random stratified and systematically stratified samples from the target area for prediction of standing volume, above-ground biomass and stem count in the target area. A range of combinations was used for the modelling process, comprising the most similar neighbour (MSN) and random forest (RF) imputation methods, three sampling designs and two predictor subset sizes. An evolutionary genetic algorithm (GA) was applied to prune the predictor variables. Diagnostic tools, including root mean square error (RMSE), bias and standard error of imputation, were employed to evaluate the results. The results showed that RF produced more accurate results than MSN (average improvement of 3.5% for a single-neighbour case with selected predictors), yet was more biased than MSN (average bias of 5.13% with RF compared to 2.44% with MSN for stem volume in a single-neighbour case with selected predictors). Combining systematically stratified auxiliary samples from the target data set with the reference data set yielded more accurate results compared to those from random and stratified random samples. Combining additional data was most influential when an intensity of up to 40% of supplementary samples was appended to the reference set. The use of GA-selected predictors resulted in reduced bias of the models. By means of bootstrap simulations of RMSE, the simulations were shown to lie within the applied non-parametric confidence intervals. The achieved results are concluded to be helpful for modelling the mentioned forest attributes by means of airborne remote-sensing data.