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Membrane and membrane process have been widely considered as one of the best candidates for mitigating CO2emissions from the combustion or utilization of fossil fuels. Various amine‐containing polymers constitute an important class of membranes, where the highly selective CO2transport is achieved by the facilitated transport mechanism. In this review, the amine–CO2chemistry is discussed in conjunction with the mechanism of the reaction‐mediated CO2transport. A wide variety of amine‐containing polymers are discussed based on two synthesis motifs: (a) polyamines with amino groups covalently bound to the polymer backbone and (b) small molecule amines embedded in a polymer matrix. This review concludes with the remarks on the facilitated transport membranes for post‐combustion carbon capture (CO2/N2) and hydrogen purification (CO2/H2). This article reviews the synthesis and utilization of polymeric facilitated transport membranes for post‐combustion carbon capture (CO2/N2) and hydrogen purification (CO2/H2). The origin of the high CO2/gas selectivity is discussed in terms of CO2–carrier chemistry and the associated reactive diffusion mechanism. The various polymeric membrane materials are classified based on their molecular motifs and the transport mechanisms of the carriers.

A two-stage membrane process featuring a partial retentate recycling is designed for using amine-containing facilitated transport membranes to decarbonize flue gases from pulverized coal power plants. A methodology of technoeconomic analysis is also developed to evaluate their technical feasibility for this separation modality. In order to account for the dependence of CO2permeance on the CO2partial pressure, the carrier saturation behavior was modeled and integrated into the process evaluation. The sensitivity study has revealed that the partial retentate recycling is the enabling factor to reduce the system footprint and energy consumption. Moreover, the mitigated carrier saturation has led to an uprising CO2permeance upon bulk CO2removal. These two features have resulted in an attractive calculated capture cost of $41.75/tonne by facilitated transport membranes that have been realized experimentally.

A Zn benzotriazolate metal–organic framework (MOF), [Zn(ZnO2CCH3)4(bibta)3] (1, bibta2–= 5,5′-bibenzotriazolate), has been subjected to a mild CH3CO2–/HCO3–ligand exchange procedure followed by thermal activation to generate nucleophilic Zn–OH groups that resemble the active site of α-carbonic anhydrase. The postsynthetically modified MOF, [Zn(ZnOH)4(bibta)3] (2*), exhibits excellent performance for trace CO2capture and can be regenerated at mild temperatures. IR spectroscopic data and density functional theory (DFT) calculations reveal that intercluster hydrogen bonding interactions augment a Zn–OH/Zn–O2COH fixation mechanism.

N-Arachidonylethanolamine (AEA) accumulates during brain injury and postmortem. Because fatty acid amide hydrolase (FAAH) regulates brain AEA content, the purpose of this study was to determine its role in the postmortal accumulation of AEA using FAAH null mice. As expected, AEA content in immediately frozen brain tissue was significantly greater in FAAH-deficient (FAAH−/−) than in wild-type mice. However, AEA content was significantly lower in brains from FAAH−/−mice at 5 and 24 h postmortem. Similarly, wild-type mice treated in vivo with a FAAH inhibitor (URB532) had significantly lower brain AEA content 24 h postmortem compared with controls. These data indicate that FAAH contributes significantly to the postmortal accumulation of AEA. In contrast, the accumulations of two other N-acylethanolamines, N-oleoylethanolamine (OEA) and N-palmitoylethanolamine (PEA), were not reduced at 24 h postmortem in either the FAAH−/−mice or mice treated with URB532. FAAH−/−mice accumulated significantly less ethanolamine at 24 h postmortem compared with wild-type mice, suggesting that FAAH activity plays a role in the accumulation of ethanolamine postmortem.

Virodhamine is a recently identified novel endocannabinoid. Cannabinoids may evoke vasorelaxation through novel receptors in the vasculature and/or through release of vasodilator peptides from sensory nerve endings. Virodhamine induced endothelium‐dependent relaxation in the rat isolated small mesenteric artery mounted in a myograph and precontracted with methoxamine. Desensitization of vanilloid receptors by capsaicin did not affect relaxation responses to virodhamine. The CB1receptor antagonist SR 141716A (3 μM), but not the more CB1‐selective blocker AM 251 (1 μM), attenuated the response, while two CB2receptor antagonists, SR 144528 (1 μM) and AM 630 (10 μM), had no effect. The novel antagonist for the putative endothelial ‘abnormal‐cannabidiol receptor’, O‐1918 (30 μM), inhibited virodhamine relaxations. Hence virodhamine may activate this novel receptor, which might also recognize SR 141716A. Inhibition of nitric oxide synthase (L‐NAME 300 μM) did not affect relaxation to virodhamine but the responses were markedly reduced when tone was induced with 60 mM KCl, suggesting a role for the activation of K+channels. The Ca2+‐activated K+channel (KCa) blockers, apamin (50 nM) and charybdotoxin (50 nM), inhibited virodhamine vasorelaxation. Combination of these blockers with SR 141716A (3 μM) caused no further inhibition. It was concluded that virodhamine relaxes the rat small mesenteric artery by endothelium‐dependent activation of KCa, perhaps via the putative abnormal‐cannabidiol receptor.

Virodhamine is a recently identified novel endocannabinoid. Cannabinoids may evoke vasorelaxation through novel receptors in the vasculature and/or through release of vasodilator peptides from sensory nerve endings. Virodhamine induced endothelium-dependent relaxation in the rat isolated small mesenteric artery mounted in a myograph and precontracted with methoxamine. Desensitization of vanilloid receptors by capsaicin did not affect relaxation responses to virodhamine. The CB1receptor antagonist SR 141716A (3 μM), but not the more CB1-selective blocker AM 251 (1 μM), attenuated the response, while two CB2receptor antagonists, SR 144528 (1 μM) and AM 630 (10 μM), had no effect. The novel antagonist for the putative endothelial ‘abnormal-cannabidiol receptor’, O-1918 (30 μM), inhibited virodhamine relaxations. Hence virodhamine may activate this novel receptor, which might also recognize SR 141716A. Inhibition of nitric oxide synthase (L-NAME 300 μM) did not affect relaxation to virodhamine but the responses were markedly reduced when tone was induced with 60 mM KCl, suggesting a role for the activation of K+channels. The Ca2+-activated K+channel (KCa) blockers, apamin (50 nM) and charybdotoxin (50 nM), inhibited virodhamine vasorelaxation. Combination of these blockers with SR 141716A (3 μM) caused no further inhibition. It was concluded that virodhamine relaxes the rat small mesenteric artery by endothelium-dependent activation of KCa, perhaps via the putative abnormal-cannabidiol receptor.

We have synthesized a family of new extractants, alkyl phenylphosphonic acids, for strontium removal by supported liquid membranes (SLMs) with strip dispersion. The stability of the SLMs has been ensured by the improved SLM with strip dispersion technique. The SLMs removed radioactive Sr-90 to the target of 8 pCi/L or lower from feed solutions of 300−1000 pCi/L. Overall mass transfer coefficient data indicate that the mass transfer resistance for the membrane phase is negligible. An analysis of mass transfer resistances shows that the interfacial resistances due to extraction and stripping reactions are dominant. Stripping with HCl was nearly quantitative and more effective than that with H2SO4. The extractant was more effective than di(2-ethylhexyl) phosphoric acid.

The cannabinoid arachidonyl ethanolamide (anandamide) caused concentration‐dependent relaxation of 5‐HT‐precontracted, myograph‐mounted, segments of rat left anterior descending coronary artery.This relaxation was endothelium‐independent, unaffected by the fatty acid amide hydrolase inhibitor, arachidonyl trifluoromethyl ketone (10 μM), and mimicked by the non‐hydrolysable anandamide derivative, methanandamide.Relaxations to anandamide were attenuated by the cannabinoid receptor antagonist, SR 141716A (3 μM), but unaffected by AM 251 (1 μM) and AM 630 (1 μM), more selective antagonists of cannabinoid CB1and CB2receptors respectively. Palmitoylethanolamide, a selective CB2receptor agonist, did not relax precontracted coronary arteries.Anandamide relaxations were not affected by inhibition of sensory nerve transmission with capsaicin (10 μM) or blockade of vanilloid VR1 receptors with capsazepine (5 μM). Nevertheless capsaicin relaxed coronary arteries in a concentration‐dependent and capsazepine‐sensitive manner, confirming functional sensory nerves were present. In contrast, capsazepine and capsaicin did inhibit anandamide relaxations in methoxamine‐precontracted rat small mesenteric arteries.Relaxations to anandamide were inhibited by TEA (1 mM) or iberiotoxin (50 nM), blockers of large conductance, Ca2+‐activated K+channels (BKCa). Gap junction inhibition with 18α‐glycyrrhetinic acid (100 μM) did not affect anandamide relaxations.This study shows anandamide relaxes the rat coronary artery by a novel mechanism. Anandamide‐induced relaxations do not involve the endothelium, degradation into active metabolites, or activation of cannabinoid CB1or CB2receptors, but may involve activation of BKCa. Vanilloid receptor activation also has no role in the effects of anandamide in coronary arteries, even though functional sensory nerves are present.

Supported liquid membranes (SLMs) are very effective for the removal and recovery of metals from waste waters and process streams since they combine extraction and stripping, into one step. The one‐step membrane process provides the maximum driving force for the separation of a targeted metal, leading to the best possible clean‐up and recovery rates. The stability of the SLM has been ensured with strip dispersion, where the aqueous strip solution is dispersed in the organic membrane solution in a mixer. The strip dispersion formed is circulated from the mixer to the membrane module to provide a constant supply of the organic solution to the membrane pores. We have identified effective SLM systems, operating at a feed pH < 3 for the removal and recovery of copper, zinc, and nickel. Goals of zero discharge and no sludge are achievable.

A total of 550 acute burn patients under the age of 15 years were admitted to the Burns Unit of Prince of Wales Hospital, Hong Kong between March 1993 and February 1999. There were 337 males and 213 females with a male to female ratio of 1.58:1. The median age was 2.5 years and the median burn size was 5% total body surface area (TBSA). Toddlers of age < 2 years accounted for 235 (42.7%) of admission. Domestic burns resulted in 481 (87.5%) injuries followed by play-related burns that caused 34 (6.2%) admissions. Scalding was the most common cause of injury, which accounted for 497 (90.4%) admissions, followed by flame burns, which resulted in 45 (8.2%) injuries. Nine patients (1.6%) had inhalation injury requiring intubation and ventilatory support. The median hospital stay was 8 days and there was no seasonal variation in admission. The majority of patients (80.2%) had their wounds healed without any operation. Only 19 out of 550 patients (3.5%) had burns of 30% TBSA or larger, and only nine patients (1.9%) had inhalation injuries. Only one patient died in this series, which yielded a mortality rate of 0.2%.

We have developed new supported liquid membrane (SLM) technology for removal and recovery of chromium from waste waters. The technology not only removes the Cr (VI) to less than 0.05 ppm in the treated effluent allowable for discharge or recycle, but also recovers the product at a high concentration of about 20% (62.3% Na2CrO4) suitable for resale or reuse. In other words, we have achieved the goals of zero discharge and no sludge. The chromium flux in its entire range from low Cr (VI) concentrations in the feed solution to high feed concentrations, at which the carrier saturation of the facilitated transport mechanism occurs, has been in good agreement with a film model. The stability of the SLM has been ensured by strip dispersion, where the aqueous strip solution is dispersed in the organic membrane solution in a mixer. The strip dispersion formed is circulated from the mixer to the membrane module providing a constant supply of the organic solution to the membrane pores.

The actions of the blood substitute diaspirin crosslinked hemoglobin (DCLHb) were investigated in rat (small mesenteric artery) and human (radial collateral artery) resistance vessels mounted in a wire myograph for isometric tension recording. DCLHb did not contract resting vessels from rats, but vasoconstrictor responses were observed in isolated arteries and perfused mesenteric beds prestimulated with threshold concentrations of methoxamine. The DCLHb contractile responses were greatly attenuated by NG-nitro-l-arginine methyl ester hydrochloride (l-NAME) or endothelial removal, whereas BQ-123 (endothelin A receptor antagonist), prazosin (1-adrenoceptor antagonist), or indomethacin (cyclooxygenase inhibitor) had no effect. Endothelium-dependent relaxations to carbachol in both rat mesenteric and human radial collateral artery were inhibited by DCLHb. Relaxations to carbachol were studied in the presence of l-NAME or 25 m MKCl to investigate the effect of DCLHb on endothelium-derived hyperpolarizing factor (EDHF) and nitric oxide, respectively. In both rat and human vessels, EDHF-mediated relaxations were not affected by DCLHb preincubation, whereas the nitric oxide component of carbachol-induced relaxations was practically abolished. In conclusion, inhibition of the effects of basal nitric oxide release underpins the vasoconstrictor effects of DCLHb. DCLHb effectively abolishes the nitric oxide component of carbachol-induced relaxation, with no effect on the EDHF-mediated component in both isolated rat mesenteric and human radial collateral arteries.

A 75-year-old man was admitted with left lower limb weakness with findings of left isolated external iliac artery aneurysm and left hydronephrosis. Doppler ultrasound and contrasted computed tomography scan demonstrated a large 18 cm iliac artery aneurysm. Endoaneurysmorrhaphy and iliofemoral bypass were performed. The patient was well and discharged 2 weeks after operation. The incidence, natural history, and management of isolated iliac artery aneurysms are discussed and the literature is reviewed.

Flexsorb HP is a new, sterically hindered amine-promoted, potassium carbonate-based process for CO2 absorption from gases. Compared to the conventional diethanolamine (DEA) promoted process, it offers considerable capacity and rate advantages. It has outstanding stability toward the corrosion inhibitor V5+, which degrades DEA. Its amine promoter aging resistance is much superior to that of DEA. It can serve as a "drop in" technology that can be used in an existing plant, leading to capacity increase without any equipment modification. For grassroots applications it requires lower investments than DEA-promoted units.

This paper reviews sterlcally-hindered amines for removal of add gases such as CO2 and H2S from gaseous streams. Steric hindrance of amines reduces carbamate stability. Moderately hindered amines are characterized by high rates of CO2 absorption and high capacities for CO2. The moderately hindered amine in use with organic solvent has considerably higher capacity than the conventional amine-solvent system for simultaneous removal of CO2and H2S from synthesis gas and natural gas. A severely-hindered-amine absorbent, characterized by a very low rate of CO2absorption, has much higher capacity and selectivity than the current industry standard, methyldiethanolamine, for selective removal of H2S from CO2-containing streams. Use of hindered amines represents new advances in gas treating. Hindered amines save energy and capital in gas treating significantly. In addition, hindered amines used commercially have much better stability than conventional amines. As of today, fourteen commercial plants use hindered amines.

The liquid membrane process can effectively separate and concentrate uranium from wet process phosphoric acid and is economically superior to solvent extraction systems. The paper describes the process, compares it to other extraction schemes, and shows how it can be used for uranium recovery. A mathematical model useful for design purposes is presented and the effect of important variables is discussed.

The increment of greenhouse gaseous emission increases the needs to find the best solution to reduce emission of its gaseous. Carbon dioxide is the main contributor which comes mainly from energy sector. Capturing CO2 from power plant does not fully solves the issue hence integrating power plant with methanation was proposed. In this paper, a pinch analysis technique is introduced to solve the challenge to implement the integrated power plant with methanation. The main drawback of the system is to deliver a sustainable and optimize capacity of hydrogen for methanation of carbon dioxide. Cascade pinch analysis is done which has been adopted from ESCA to calculate optimal hydrogen supply and hydrogen storage. From the analysis, after five iteration, the hydrogen supply capacity is obtained which is 281.38 Wh. The hydrogen storage capacity can also be determined which is 1352.52 Wh. Through the case study presented, it has proven that pinch analysis provides a simple methodology to solve the optimization issue of hydrogen supply and demand for integrated power plant with methanation system.

The retrieval of spleen after laparoscopic splenectomy has long been a problem. Frequently, it is necessary to extend the wound for retrieving the spleen intact and to prevent potential spillage of splenic tissue into the peritoneal cavity. We describe the application of the liposuction unit to remove the spleen piecemeal after laparoscopic splenectomy. We have found this technique easy to apply and safe, without the necessity of excessive wound extension, while preserving splenic tissue for histologic examination.

Plasma immersion ion implantation of hydrogen with low kinetic energy (1 kV) was used to passivate solar cells to increase efficiency. The plasma sheath encloses the wafer cell and hydrogen ions can be implanted into the entire cell surface. The passivation is omnidirectional, and is particularly effective at the edge surface of the solar cell. The large diffusion length of carriers in Si solar cell is susceptible to edge defects, since the photo-generated carriers can diffuse to the edge surfaces and recombine to degrade the efficiency. Moreover, the dielectric/silicon interface can be effectively passivated due to energetic hydrogen from plasma. For small-area cell, an increase in relative efficiency of 4.4% was obtained after a 90 s plasma immersion ion implantation treatment. Both the external quantum efficiency for 400–500 nm wavelength photons and photoluminescence intensity increase by ∼6% and ∼29% relatively.