Characteristics of the medical waste generated at the Jordanian hospitals

Recently, Jordan has witnessed increased amounts of medical waste generated at different healthcare facilities. This has resulted in issuance of Medical Waste Regulation that aimed at regulating the management processes of such hazardous waste. To provide information on medical waste generation rates, composition and statistical characteristics, a comprehensive sampling survey was initiated after a regulatory definition of the medical waste was established. Hospitals from Public, private and educational categories were covered by the survey. This paper presents the findings of the survey. The average generation rates ranged from 0.29 to 1.36 kg/bed/day, while in terms of patient numbers it is from 0.36 to 0.87 kg/patient/day. The total daily amount of medical waste generated at the Jordanian hospitals was estimated to be 6 tones/day. The daily amounts of medical waste generated at King Abdullah University Hospital were found to follow a log normal probability distribution. Physical composition analysis of the medical waste, which conducted based on the categories identified by the Jordanian Regulation, indicated that the infectious waste category is the highest, followed by sharps category and finally pathological, cytotoxic and pharmaceutical categories were the lowest. The study concluded that all hospitals covered by the survey are practicing segregation of hazardous medical waste from general medical waste. However, the segregation process in some hospitals is still inefficient and there is a potential for improvements toward minimizing the hazardous medical waste generation.     

Comparison of Canola and Soy Flour with Added Isocyanate as Wood Adhesives

Canola is widely grown in the northern latitudes for its vegetable oil, generating large quantities of residual, low value canola flour used as animal feed. The common wood adhesive poly(diphenylmethylene diisocyanate) (pMDI) should react with the wide variety of functional groups in proteins. Therefore, it would seem that canola flour with added pMDI could be an effective adhesive. Two main questions are addressed in this study: How do the wood adhesive properties of canola flour compare to the better-studied soy flour? How well do proteins, which contain an abundance of functional groups, cure with the very reactive pMDI? These questions were addressed using the small-scale adhesive strength test ASTM D-7998, with various adhesive formulations and bonding conditions for canola flour plus pMDI compared to soy adhesives. The more challenging wet cohesive bond strength was emphasized because the dry strengths were usually very good. Generally, soy adhesives were better than canola ones, as was the polyamidoamine-epichlorohydrin cross-linker compared to pMDI, but these generalizations can be altered by the conditions selected. Three-ply plywood tests supported the small-scale test results.     

Review of corrosion of refractory in gaseous environment

Advancing high temperature technologies pushes the envelope of the service conditions to new extremes. However, corrosion of refractories substantially decreases the service life and causes unscheduled shutdown of manufacturing and processing plants. In this paper, corrosion of refractories in gaseous environments is reviewed. The corrosion mechanisms of alumina refractories, including alumino-silicates and zirconia as oxide, and silicon carbide as non-oxide refractory are emphasized due to their broad array of applications. It is shown that carbonaceous atmosphere and water vapor are detrimental for the oxide refractories. Interaction with water vapor leads to formation of the volatile species and subsequent recession of the refractories. Carbonaceous atmosphere leads to the decomposition of even mullite, which is categorized as neutral refractory due to its excellent thermochemical stability. Oxidizing atmosphere with water vapor dominates the corrosion of non-oxide refractories. Presence of impurities, even parts per million level, in the gas stream such as alkali vapor and halogens can alter the corrosion mechanisms and favor “hot corrosion.”     

Polyurethane nanocomposites with click‐coupled nanodiamonds exhibiting enhanced mechanical and shape memory effects

Poly(?‐caprolactone)diol (PCL)–functionalized nanodiamonds (f‐NDs) were synthesized using a click chemistry reaction between the azide‐moiety PCL and alkyne‐moiety NDs and were incorporated into shape memory polyurethane (PU) at f‐ND concentrations of 0, 0.5, 1, and 2 wt % to produce high‐performance shape memory nanocomposites. The PU/f‐ND nanocomposites exhibited better shape recovery, shape recovery stress, and breaking stresses than pure PU. Shape recovery of greater than 95% was demonstrated for all the nanocomposites in the third cycle, and the shape recovery stresses increased significantly with the f‐ND content. These enhanced mechanical and shape recovery properties are ascribed to increased interactions between the f‐NDs and PU matrix due to incorporation of click‐coupled f‐NDs. The click‐coupled NDs can be used as nanofillers to enhance the mechanical and shape memory properties of polymers. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 45465.     

Influence of nanoclay on urea–glyoxalated lignin–formaldehyde resins for wood adhesive

In this research, the influence of nanoclay on urea–glyoxalated lignin–formaldehyde (GLUF) resin properties has been investigated. To prepare the GLUF resin, glyoxalated soda baggase lignin (15 wt%) was added as an alternative for the second urea during the UF resin synthesis. The prepared GLUF resin was mixed with the 0.5%, 1%, and 1.5% nanoclay by mechanically stirring for 5 min at room temperature. The physicochemical properties of the prepared resins were measured according to standard methods. Then the resins were used in particleboard production and the physical and mechanical properties of the manufactured panels were determined. Finally, from the results obtained, the best prepared resin was selected and its properties were analyzed by differential scanning calorimetry (DSC), Fourier transform infrared spectrometry (FTIR), and X-ray diffractometry (XRD). Generally the results indicated that the addition of sodium-montmorillonite (NaMMT) up to 1.5% appears to improve the performance of GLUF resins in particleboards. The results also showed that nanoclays improved mechanical strength (modulus of elasticity (MOE), Modulus of Rupture (MOR), and internal bond (IB) strength) of the panels bonded with GLUF resins. The panels containing GLUF resin and nanoclay yielded lower formaldehyde emission as well as water absorption content than those made from the neat GLUF resins. XRD characterization indicated that NaMMT only intercalated when mixed with GLUF resin. Based on DSC results, the addition of NaMMT could accelerate the curing of GLUF resins. The enthalpy of the cure reaction (ΔH) of GLUF resin containing NaMMT was increased compared with neat GLUF resin. Also the results of FTIR analysis indicated that addition of NaMMT change the GLUF resins structures.     

Tailored dielectric and mechanical properties of noncovalently functionalized carbon nanotube/poly(styrene‐b‐(ethylene‐co‐butylene)‐b‐styrene) nanocomposites

The preparation of high‐dielectric poly(styrene‐b‐(ethylene‐co‐butylene)‐b‐styrene) (SEBS) composites containing functionalized single‐walled carbon nanotubes (f‐SWCNTs) noncovalently appended with dibutyltindilaurate are reported herein. Transmission electron microscopy and X‐ray photoelectron and Raman spectroscopy confirmed the noncovalent functionalization of the SWCNTs. The SEBS‐f‐SWCNT composites exhibited enhanced mechanical properties as well as a stable and high dielectric constant of approximately 1000 at 1 Hz with rather low dielectric loss at 2 wt% filler content. The significantly enhanced dielectric property originates from the noncovalent functionalization of the SWCNTs that ensures good dispersion of the f‐SWCNTs in the polymer matrix. The f‐SWCNTs also acted as a reinforcing filler, thereby enhancing the mechanical properties of the composites. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

‘Graft from’ polymerization on colloidal silica particles: elaboration of alkoxyamine grafted surface by in situ trapping of carbon radicals

We report in this paper an original method for the synthesis of polybutylacrylate grafted on silica particles. First, we use the Stoeber method to synthesize silica particles with a narrow size distribution. An initiator for radical-chain controlled polymerization is then grafted on the silica surface in two steps. Trimethoxysilylpropyl methacrylate (TPM) is first grafted on silica by simple condensation. Then, a alkoxyamine initiator N-tert-butyl-N-1-diethylphosphono2,2-dimethylpropyl-0,1-methoxycarbonyl ethylhydroxylamine (MONAMS) reacts with the CC double bond of the TPM to form the grafted initiator of radical polymerization. The last step is the grafting of butylacrylate. For this, we use living free radical polymerization that allows to control the molecular weight and the polydispersity of the polybutylacrylate chains. We show that this synthesis method makes it possible to obtain a colloidal suspension of silica particles having a mean size of about 88 nm, a weak polydispersity and an important grafting density of polybutylacrylate (PBA).     

Graft copolymerization with a new class of acidic peroxo salts as initiator. V. Grafting of methyl methacrylate onto jute fiber using potassium monopersulfate catalyzed by Fe(II)

Graft copolymerization of methyl methacrylate (MMA) onto jute fibers was studied in an aqueous solution using a new class of acidic peroxo salt, potassium monopersulfate, as initiator, under the catalytic influence of Fe(II) under nitrogen atmosphere. The grafting reaction was influenced by the reaction time, temperature, and concentrations of monomer, initiator, and jute fibers. The grafting reactions have also been studied in the presence of various salts and solvents. The maximum grafting percent (385.4%) has been observed at 35°C for the concentration of monomer (1.4082M), initiator (12.9 × 10^?3M), catalyst (2.5 × 10^?4M), and solvent (acetic acid) composition of (40:60) for a reaction time of 6 h. From the experimental results a suitable mechanism for the graft initiation and termination has been put forth. The graft copolymers have been characterized, and their improved properties such as tensil strength tested.     

Grain boundaries between bismuth nanocrystals

Grain boundaries in thin Bi(1 1 0) films deposited on highly oriented pyrolytic graphite are investigated at atomic resolution using scanning tunnelling microscopy and high-resolution transmission electron microscopy. We find preferred misorientation angles Θ equal to 216°, 87°, 49°, 31°, 20°, 12° and 5°, the majority of which can be classified as large-angle boundaries. We find good agreement between the experimental results and a model of the tilt [1 1 0] grain boundary developed here. A method for estimating the surface unit cell based on measurement of dihedral angle in low-resolution images is also developed.