A decontamination system for chemical weapons agents using a liquid solution on a solid sorbent

A decontamination system for chemical warfare agents was developed and tested that combines a liquid decontamination reagent solution with solid sorbent particles. The components have fewer safety and environmental concerns than traditional chlorine bleach-based products or highly caustic solutions. The liquid solution, based on Decon Greentrade mark, has hydrogen peroxide and a carbonate buffer as active ingredients. The best solid sorbents were found to be a copolymer of ethylene glycol dimethacrylate and n-lauryl methacrylate (Polytrap 6603 Adsorber); or an allyl methacrylate cross-linked polymer (Poly-Pore E200 Adsorber). These solids are human and environmentally friendly and are commonly used in cosmetics. The decontaminant system was tested for reactivity with pinacolyl methylphosphonofluoridate (Soman, GD), bis(2-chloroethyl)sulfide (Mustard, HD), and S-(2-diisopropylaminoethyl) O-ethyl methylphosphonothioate (VX) by using NMR Spectroscopy. Molybdate ion (MoO(4)(-2)) was added to the decontaminant to catalyze the oxidation of HD. The molybdate ion provided a color change from pink to white when the oxidizing capacity of the system was exhausted. The decontaminant was effective for ratios of agent to decontaminant of up to 1:50 for VX (t(1/2) < or = 4 min), 1:10 for HD (t(1/2) < 2 min with molybdate), and 1:10 for GD (t(1/2) < 2 min). The vapor concentrations of GD above the dry sorbent and the sorbent with decontamination solution were measured to show that the sorbent decreased the vapor concentration of GD. The E200 sorbent had the additional advantage of absorbing aqueous decontamination solution without the addition of an organic co-solvent such as isopropanol, but the rate depended strongly on mixing for HD.     

Investigation of Water Absorption and Diffusion in Microparticles Containing Xylitol to Provide a Cooling Effect by Thermal Analysis

Polyurethane microparticles containing xylitol as a sweat sensor system were prepared by interfacial polymerization. The structural and thermal properties of the resultant microparticles were studied. The surface morphology and chemical structure of microparticles were investigated using an optical microscope (OM) and a Fourier-transform infrared spectroscope (FTIR), respectively. The thermal properties of samples were investigated by thermogravimetric analysis (TGA) and by differential scanning calorimetry (DSC). Thus, two types of microparticles were synthesized by varying the percentage of monomers introduced. The obtained morphology is directly related to the synthesis conditions. DSC analysis indicated that the mass content of crystalline xylitol was up to 63.8 %, which resulted in a high enthalpy of dilution of 127.7 J · g⁻¹. Furthermore, the water release rate monitored by TGA analysis was found to be faster from the microparticles than from raw xylitol. Thus, the microparticles could be applied for thermal energy storage and moisture sensor enhancement.     

Mechanism of bone loss after liver transplantation: A histomorphometric analysis

This work analyzed the rat soleus muscle after single and recurrent contusions at different stages of regeneration. A noninvasive contusion was produced by a type of drop-mass equipment. The posterior region of the right hind limb received a trauma and both right and left soleus muscles were analyzed 1, 4, and 6 days after a single contusion (1x), and 6 and 30 days after periodic contusions (10x, one trauma per week for 10 weeks). Single contusion: there was no significant difference between right and left soleus muscle weight. All animals showed abundant signs of acute damage in the right soleus. AChE activity was identified in regeneration segments of the right soleus. Periodic contusions: there was an increase in the right soleus muscle weight (alpha = 5%) only in the animals evaluated 6 days after periodic contusions. The right soleus muscle showed a high incidence of chronic signs of damage, such as split fibers and a centralized nucleus, which predominated when compared with the acute signs. Right soleus muscles showed split fibers with AChE activity in both the proximal and middle regions. There was no difference in the incidence of muscle fiber types (I, II, and IIC) between right and left soleus muscles after periodic contusions. Skeletal muscle contusion is common in humans, especially in sport activities, where repetitive traumas are also frequent. The results of this work indicate that despite the regeneration process there is an important change in the morphological aspect of regenerated muscle fibers, which possibly affect muscle performance.     

Selective Hydrogenation of 1,3‐Butadiene to 1‐Butene by Pd(0) Nanoparticles Embedded in Imidazolium Ionic Liquids

The reduction of Pd(acac)₂ (acac=acetylacetonate), dissolved in 1‐n‐butyl‐3‐methylimidazolium hexafluorophosphate (BMI⋅PF₆) or tetrafluoroborate (BMI⋅BF₄) ionic liquids, by molecular hydrogen (4 atm) at 75 °C affords stable, nanoscale Pd(0) particles with sizes of 4.9±0.8 nm. Inasmuch as 1,3‐butadiene is at least four times more soluble in the BMI⋅BF₄ than butenes, the selective partial hydrogenation could be performed by Pd(0) nanoparticles embedded in the ionic liquid. Thus, the isolated nanoparticles promote the hydrogenation of 1,3‐butadiene to butenes under solventless or multiphase conditions. Selectivities up to 97% in butenes were observed in the hydrogenation of 1,3‐butadiene by Pd(0) nanoparticles embedded in BMI⋅BF₄ under mild reaction conditions (40 °C and 4 atm of hydrogen at constant pressure). Selectivities up to 72% in 1‐butene were achieved at 99% 1,3‐butadiene conversion, 40 °C and 4 atm of constant pressure of hydrogen. The amounts of butane (fully hydrogenated 1,3‐butadiene) and cis‐2‐butene products are marginal and the butenes do not undergo isomerisation process, indicating that the soluble Pd(0) nanoparticles possess a pronounced surface‐like rather than homogeneous‐like catalytic properties.     

Mobile Phase Effects in Rh/Sulfonated Phosphine/Molten Salts Catalysed the Biphasic Hydroformylation of Heavy Olefins

Rh(acetylacetonate)(CO)₂/sulfonated-Xantphos dissolved in pure 1-n-butyl-3-methylimidazolium hexafluorophosphate ionic liquid catalyses the hydroformylation of heavy olefins (C₈–C₁₂) with selectivities (up to 99% in n-aldehydes). The selectivity is strongly influenced by the nature of the ionic phase and co-solvent.     

Multiple connexins localized to individual gap-junctional plaques in human myometrial smooth muscle.

The synchronous contractions of the uterus in labour depend on electrical coupling of myometrial smooth muscle cells by gap junctions. In the human myometrium, gap junctions are scarce in the non-pregnant uterus, but become abundant at term in preparation for labour. We have previously demonstrated that in the human myometrium at term, three different gap-junctional proteins are expressed, connexins 43, 45, and 40. These connexins are known to have distinctive functional capacities in in vitro expression systems but whether, in the human myometrium in vivo, they are co-assembled into the same gap junction or form different types of gap junction has previously been unclear. By applying triple immunogold labelling to sections of Lowicryl-embedded tissue for electron microscopy, together with complementary immunoconfocal microscopy, we demonstrate here that connexins 43, 45, and 40 are commonly present as mixtures within the same gap-junctional plaque. While all gap junctions contain connexin43, the relative signal for each connexin type varies between individual junctions. The presence within single gap-junctional plaques of three different connexins, each with the potential for conferring distinctive channel properties, suggests an inherent versatility for modulation of smooth muscle cell intercellular communication properties during human parturition.     

Alternative Synthesis of a Dialkylimidazolium Tetrafluoroborate Ionic Liquid Mixture and its Use in Poly(acrylonitrile‐butadiene) Hydrogenation

An alternative synthesis of a dialkylimidazolium ionic liquid mixture is developed in order to produce inexpensive solvents for biphasic hydrogenation of poly(acrylonitrile‐butadiene) rubbers (NBR) catalyzed by RuHCl(CO)(PCy₃)₂.     

Incorporation of manganese complexes into xylanase: new artificial metalloenzymes for enantioselective epoxidation

Here we report the best artificial metalloenzyme to date for the selective oxidation of aromatic alkenes; it was obtained by noncovalent insertion of Mn^III‐meso‐tetrakis(p‐carboxyphenyl)porphyrin [Mn(TpCPP), 1 ‐Mn] into a host protein, xylanase 10A from Streptomyces lividans (Xln10A). Two metallic complexes—N,N′‐ethylene bis(2‐hydroxybenzylimine)‐5,5′‐dicarboxylic acid Mn^III [(Mn‐salen), 2 ‐Mn] and 1 ‐Mn—were associated with Xln10A, and the two hybrid biocatalysts were characterised by UV–visible spectroscopy, circular dichroism and molecular modelling. Only the artificial metalloenzyme based on 1 ‐Mn and Xln10A was studied for its catalytic properties in the oxidation of various substituted styrene derivatives by KHSO₅: after optimisation, the 1 ‐Mn ‐ Xln10A artificial metalloenzyme was able to catalyse the oxidation of para‐methoxystyrene by KHSO₅ with a 16 % yield and the best enantioselectivity (80 % in favour of the R isomer) ever reported for an artificial metalloenzyme.     

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