PC Units Research Articles

Experimental programme in CIUDEN's CO 2 capture technology development plant for power generation

Energy projections made by the World Energy Council, the International Energy Agency (IEA) and the US Energy Information Administration give similar pictures of the dominant role of fossil fuel in the future primary energy global demand and the necessity of incorporating CCS Technologies as part of the portfolio of solutions to reach the target world emission reduction in the coming years. Without CCS, CO 2 emission levels by 2050 are expected to increase by 70%. One of the most relevant initiatives for the deployment of CCS technologies is promoted by the Spanish Government through the institution Fundacion Ciudad de la Energia (CIUDEN). CIUDEN is developing a complete programme focusing on the development of CCT and CCS technologies in Europe. CIUDEN's CO 2 capture programme includes the construction and operation of a Technology Development Plant (TDP) in NW Spain (El Bierzo). The construction of the installation started in November 2008 and incorporates the following technologies: fuel preparation system, pulverised coal boiler (20 MWth), circulating fluidized bed boiler (30 MWth), biomass gasifier (3 MWth), flue gas cleaning train for NO x , dust and SO x, and CO 2 processing unit. This paper describes CIUDEN's TDP for CO 2 capture, focusing on the particularities of the installation and design, and especially on the PC unit and equipment required for its operation. The experimental programme currently under way is also described. Results are expected to be an extraordinary advance in the development and strengthening of CCT and CCS technologies, particularly oxycombustion.

The Effectiveness and Adverse Effects profile of “Burst” Ketamine in Refractory Cancer Pain: The Vcog Pm 1-00 Study

This multi-centre study of adjuvant "burst" ketamine in palliative care in-patients documents its effectiveness, duration of pain relief, and adverse effects (AE) profile. Patients received a three-to-five day continuous subcutaneous infusion (CSCI) of ketamine escalated from 100 to 300 to 500 mg/24 hours if required. When the effective or maximum tolerated dose was attained, the infusion was continued for three days and each patient assessed as a responder or non-responder using strict criteria. The response rate was 22/44 (50 percent), with 4 (9 percent) becoming pain-free. Pain relief lasting two or more weeks was documented in 50 percent of responders. AEs were documented daily using the National Cancer Institute (NCI) Common Toxicity Criteria 0-4 scales. There were 11 grade 3 and 4 neurological AEs. However, no responders elected to cease treatment early due to neurological AEs. We concluded that this protocol in the controlled environment of an in-patient PC unit is relatively safe and simple with reasonable effectiveness.

Synthesis and Nonlinear Optical Properties of Tetrahedral Octupolar Phthalocyanine-Based Systems

Two series of tetrahedral phthalocyanine-based systems presenting a central carbon or silicon atom have been synthesized and fully characterized. Ethynyl spacers connect the peripheral Pc units to the central core. Some of the structures contain four identical Pc moieties, whereas other ones bear either an electron-withdrawing or an electron releasing group in the fourth subunit. The synthetic strategy consisted in metal mediated coupling reactions between tri-tert-butylethynylphthalocyanine and the corresponding methane or silane derivatives. A second-order nonlinear optical (NLO) study, through hyper-Rayleigh scattering measurements, reveals that, by combining centrosymmetrical moieties that are not second-order NLO active by themselves, in an octupolar fashion, a large second-order NLO response is achieved, in contrast to classical octupolar combinations of donor-acceptor NLO active dipolar moieties. In particular, the C-centered tetramer exhibits a large beta(HRS) value, which is among the highest reported so far for octupolar Pc-based molecules. Interestingly, carbon-centered molecules show a better NLO response with respect to the silicon-centered ones, probably due to a different effective symmetry, largely T(d) for the C-centered compounds and D(2d) for the Si-centered systems. While other design strategies for second-order NLO effects have always fundamentally kept on relying on the old dipolar paradigm (even though the resulting molecular structure was octupolar--the most striking exponent of this is the octupolar 1,3,5-triamino-2,4,6-trinitrobenzene molecule, a simple octupolar expansion of the dipolar p-nitroaniline), we here present for the first time that the octupolar symmetry by itself, realized by four nondipolar moieties in a tetrahedral arrangement, results also in a large second-order nonlinear response.

A phthalocyanine–mestranol conjugate for photodynamic therapy prepared via click chemistry

Introduction of an azide group onto the periphery of a photodynamically effective phthalocyanine (Pc) derivative gives a useful building block for the preparation of Pc conjugates via Cu(I)-catalyzed azide-alkyne 1,3-dipolar cycloaddition (‘click chemistry’). In this way, Pc–mestranol and Pc–hept-1-yne conjugates (for comparison purposes) are synthesized and their absorption, photochemical, and photophysical properties are studied. The conjugate retains the advantageous photophysical and photochemical properties of Pc. Conjugation with mestranol may lead to improved localization in tumors whereas the Pc unit is responsible for the photodynamic effect.

Ball-type supramolecular metallophthalocyanines with eight perfluorodecyl units: chemosensors for SO2 and electrocatalysts for oxygen reduction

Heptadecafluorodecyl-substituted cofacial or ball-type bis-metallophthalocyanines (BTMPcs) have been prepared. The redox properties of the complexes and their catalytic activities for oxygen reduction were studied. The occurrence of stepwise one-electron redox processes during the voltammetric measurements in solution suggested the formation of stable mixed-valence species of the complexes, as a result of the intramolecular interactions between two cofacial Pc units. The ball-type Co(ii) complex displayed excellent catalytic activity for oxygen reduction which is probably due to the rigid cofacial structure involving two redox-active metal centers, which are capable of binding O(2). dc and ac conduction properties of BTMPcs [M = Co(ii) and Cu(ii) ]thin films have been investigated in the frequency range of 40 to 10(5) Hz and temperature 290-440 K. The dc results showed an activated conductivity dependence on temperature for all films. The analysis of the obtained data showed that the correlated barrier hopping (CBH) model is the dominant conduction mechanism for electron transport in the films. The gas sensing properties of the films for SO(2) were also investigated over the same temperature range. Although a very high response to SO(2) gas has been obtained for the film of at room temperature, the film of was not sensitive to the same gases.

Architecture and scalability of a high-speed traffic measurement platform with a highly flexible packet classification

Evolving network technologies, new web services and changing usage patterns continuously change traffic characteristics. But a thorough understanding of the traffic is the basis for many applications in networking. Thus, it is crucial to analyze up-to-date traffic traces collected by passive measurements in many relevant network contexts. As the traces' quality defines the significance of such analysis, the measured data is required to be complete, temporally accurate and reliable. This is especially challenging for measurements on high-speed links. In this paper, we present a scalable architecture for a high-speed, passive measurement platform for obtaining highly accurate packet traces. Its functional blocks are distributed to a specialized hardware unit and a commodity PC unit according to their specific requirements. For pre-processing, the hardware unit integrates a protocol-aware classification and filtering module which allows an easy definition of classification and filtering rules. We analyze the platform's scalability and support this by a implementation with current FPGA technology and a standard server PC.

The value of post-combustion carbon dioxide capture and storage technologies in a world with uncertain greenhouse gas emissions constraints

By analyzing how the largest CO 2 emitting electricity-generating region in the United States, the East Central Area Reliability Coordination Agreement (ECAR), responds to hypothetical constraints on greenhouse gas emissions, the authors demonstrate that there is an enduring role for post-combustion CO 2 capture technologies. The utilization of pulverized coal generation with carbon dioxide capture and storage (PC + CCS) technologies is particularly significant in a world where there is uncertainty about the future evolution of climate policy and in particular uncertainty about the rate at which the climate policy will become more stringent. The paper's analysis shows that within this one large, heavily coal-dominated electricity-generating region, as much as 20–40 GW of PC + CCS could be operating before the middle of this century. Depending upon the state of PC + CCS technology development and the evolution of future climate policy, the analysis shows that these CCS systems could be mated to either pre-existing PC units or PC units that are currently under construction, announced and planned units, as well as PC units that could continue to be built for a number of decades even in the face of a climate policy. In nearly all the cases analyzed here, these PC + CCS generation units are in addition to a much larger deployment of CCS-enabled coal-fueled integrated gasification combined cycle (IGCC) power plants. The analysis presented here shows that the combined deployment of PC + CCS and IGCC + CCS units within this one region of the U.S. could result in the potential capture and storage of between 3.2 and 4.9 Gt of CO 2 before the middle of this century in the region's deep geologic storage formations.

Annulated Dinuclear Metal-Free and Zn(II) Phthalocyanines: Photophysical Studies and Quantum Mechanical Calculations

The results of steady-state and time-resolved absorption and fluorescence experiments as well as quantum mechanical density functional theory (DFT) calculations of metal-free and Zn(II) mononuclear and dinuclear (sharing a common benzene ring) phthalocyanines are presented. A detailed comparison between measured and calculated absorption spectra of all compounds is done, showing a good agreement between theory and experiment. The NH tautomerization for phthalocyanines with an extended pi-electron system was shown for the first time at room temperature. The photophysical properties of all possible NH tautomers of metal-free dinuclear Pc have been fully characterized. In the first tautomer, Pc(parallel), both pairs of hydrogen atoms are parallel to the connection line of two Pc units. The maximum of the lowest-energy Q absorption band, lambda abs, in Pc(parallel) is located at 832 nm, whereas the spectral position of the fluorescence maximum lies at lambdafl=837 nm. The second NH tautomer, Pc(perpendicular) (lambdaabs=853 nm, lambdafl=860 nm), presents the two pairs of hydrogen atoms perpendicularly orientated to the covalent axis, and the third one, Pc(mix) (lambdaabs=864 nm, lambdafl=872 nm), contributing in a minor extend to the absorption and fluorescence spectra of the metal-free dinuclear phthalocyanine, has one perpendicular and one parallel pair of hydrogen atoms. Obviously, only one configuration exists in the case of the Zn(II)-containing dinuclear phthalocyanine (lambdaabs=845 nm, lambdafl=852 nm).

Synthesis, characterization, electrochemical and CO 2 sensing properties of novel mono and ball-type phthalocyanines with four phenolphthalein units

The novel mono metallo [Zn(II) 4 and Co(II) 5] and ball-type or cofacial bis-metallo [Zn(II) 6 and Co(II) 7] phthalocyanines have been synthesized from 3, which can be obtained by the reaction of 4-nitrophthalonitrile 1 with 3,3-bis(4-hydroxy-phenyl)isobenzofuran-1(3 H)-one 2 (phenolphthalein). The phthalocyanines have been characterized by elemental analysis, UV–vis, IR, 1H NMR, and mass spectroscopy. The redox behavior of the complexes was investigated by cyclic voltammetry and controlled-potential coulometry. The electrochemical measurements suggested the formation of mixed-valent species during the redox processes of bis-metallophthalocyanines 6 and 7, as a result of the intramolecular interactions between two cofacial Pc units. The effect of temperature on the CO 2 sensing properties of a spin-coated thin film of 7 was also investigated.

Further Investigation of the Impact of the Co-combustion of Tire-derived Fuel and Petroleum Coke on the Petrology and Chemistry of Coal Combustion Products

A Kentucky cyclone-fired unit burns coal and tire-derived fuel, sometimes in combination with petroleum coke. A parallel pulverized combustion (pc) unit at the same plant burns the same coal, without the added fuels. The petrology, chemistry, and sulfur isotope distribution in the fuel and resulting combustion products was investigated for several configurations of the fuel blend. Zinc and Cd in the combustion products are primarily contributed from the tire-derived fuel, the V and Ni are primarily from the petroleum coke, and the As and Hg are probably largely from the coal. The sulfur isotope distribution in the cyclone unit is complicated due to the varying fuel sources. The electrostatic precipitator (ESP) array in the pc unit shows a subtle trend towards heavier S isotopic ratios in the cooler end of the ESP.

Bacterial contamination of platelet concentrates: results of a prospective multicenter study comparing pooled whole blood–derived platelets and apheresis platelets

The GERMS Group initiated a prospective multicenter study to assess prevalence and nature of bacterial contamination of pooled buffy-coat platelet concentrates (PPCs) and apheresis platelet concentrates (APCs) by routine screening with a bacterial culture system. In nine centers overall, 52,243 platelet (PLT) concentrates (15,198 APCs, 37,045 PPCs) were analyzed by aerobic and anaerobic cultures (BacT/ALERT, bioMérieux). In 135 PLT concentrates (PCs; 0.26%), bacteria could be identified in the first culture (0.4% for APCs vs. 0.2% for PPCs; p < 0.001). In 37 (0.07%) of these PC units, the same bacteria strain could be identified in a second culture from the sample bag and/or the PC unit. The rate of confirmed-positive units did not differ significantly between APC (0.09%; 1/1169) and PPC units (0.06%; 1/1544). Bacteria from skin flora (Propionibacterium acnes, Staphylococcus epidermidis) were the most prevalent contaminants. Median times to first positive culture from start of incubation were 0.7 and 3.7 days in aerobic and anaerobic cultures for confirmed-positive units. With a "negative-to-date" issue strategy, most PC units (55%) had already been issued by time of the first positive culture. The rate of confirmed bacterial contamination of PC units was low. Nevertheless, clinicians must be aware of this risk. The risk of bacterial contamination does not warrant universal preference of APCs. It must be questioned whether routine bacterial screening by a culture method can sufficiently prevent contaminated products from being transfused due to the delay until a positive signal in the culture system and due to false-negative results.

Treatment of Pathological Humeral Shaft Fractures with Unreamed Humeral Nail

The purpose of this study is to analyze the results of intramedullary fixation of pathological humeral shaft fractures using an unreamed humeral nail (UHN). Twenty-one consecutive patients with 24 humeri fractured secondary to metastatic disease were retrospectively reviewed. The primary tumors included carcinomas of breast (11), kidney (2), multiple myeloma (2), colon (2), prostate (1), thyroid (1), lymphoma (1) and unknown origin (1). All fractures were stabilized with antegrade unreamed humeral nailing. Cemented technique was performed in 5 procedures. The mean age was 64 (range, 40-86), male to female ratio 6:15. Blood loss was unremarkable in 19 patients (22 procedures). Two patients who underwent fixation of additional pathological fractures during the same operation were given a total of 3 units of PC perioperatively. Mean postoperative hospitalization period due to one UHN procedure alone was 3 days (range, 2-7 days). Two patients died of their disease within 3 weeks of surgery. The remaining 19 patients returned to nearly normal function within 6 weeks after nailing. One patient developed postoperative local wound cellulitis. Relief of pain was rated as good in all but one patient. Adjuvant therapy was given in 20 procedures. Bony union was achieved in 88% (15/17) of all the cases where the patient had survived a minimum of 3 months. Unreamed humeral nailing of the pathological humeral shaft fractures provides immediate stability and pain relief, minimum morbidity and early return of function to the extremity.

PIC microcontroller-based RF wireless ECG monitoring system

This paper presents a radio-telemetry system that provides the possibility of ECG signal transmission from a patient detection circuit via an RF data link. A PC then receives the signal through the National Instrument data acquisition card (NIDAQ). The PC is equipped with software allowing the received ECG signals to be saved, analysed, and sent by email to another part of the world. The proposed telemetry system consists of a patient unit and a PC unit. The amplified and filtered ECG signal is sampled 360 times per second, and the A/D conversion is performed by a PIC16f877 microcontroller. The major contribution of the final proposed system is that it detects, processes and sends patients ECG data over a wireless RF link to a maximum distance of 200 m. Transmitted ECG data with different numbers of samples were received, decoded by means of another PIC microcontroller, and displayed using MATLAB program. The designed software is presented in a graphical user interface utility.

Potassium Phthalocyanine, KPc: One-Dimensional Molecular Stacks Bridged by K+ Ions

We report the synthesis of potassium phthalocyanine (KPc) and its structural characterization by synchrotron X-ray powder diffraction. We find that while KPc adopts the beta-polymorphic structural type (monoclinic space group P21/a) common for many MPc solids, its structure is characterized by unique features. The K+ ions, which are statistically disordered over two symmetry-equivalent positions, reside in the intrastack spacing of the rodlike molecular assemblies and strongly bond equidistantly to selected N atoms of the two neighboring Pc rings along the chain direction with an unusual 5-fold coordination. The K+-stuffed slipped stacks of Pc units display much greater intrastack and slippage distances than those of other beta-MPc polymorphs. They may be thought as comprising disordered dimeric (Pc)22- units; this leads to electron pairing and is consistent with the observed nonmagnetic response of the system.

First Synthesis of Symmetrical and Unsymmetrical Conjugated Trinuclear Phthalocyanines Covalently Linked by Ethynyl Bridges

For the first time, symmetrical and unsymmetrical π-electron-conjugated trinuclear phthalocyanines (Pcs) were syn­thesized with the Pc units connected directly by ethynyl linkages. Symmetrically alkoxy-substituted bridged ethynylphthalocyaninatozinc(II) triad was prepared by direct Sonogashira cross-coupling reaction between suitable diiodo Pc and alkynyl Pc derivatives. Nevertheless, the synthesis of the Pc-based triad having a donor-­acceptor electron character was carried out by means of co-cyclo­tetramerization of two different phthalonitriles, namely 4,5-bis(propylsulfonyl)phthalonitrile and 4,5-[hexa(butoxy)ethynylphthalo-cyaninatozinc(II)]phthalonitrile in the presence of a cobalt(II) salt.

Miniature Thomson-type spectrometer for mass-and energy-analysis of pulsed plasma-ion streams

The paper describes the construction and tests of a new miniature mass-spectrometer of the Thomson type, which has been designed especially for plasma-ion measurements inside vacuum experimental chambers, i.e. near the electrode outlets. This ion spectrometer enables ion mass-and energy-analysis to be performed at conditions, which are unavailable for typical ion-spectrometers placed outside the vacuum chamber. In order to record the investigated ions the use is made of solid-state nuclear-track detectors of the CR-39 or PM-355 type. A quantitative analysis of recorded ion tracks is carried out by means of an optical microscope equipped with a CCD camera coupled with a PC unit. Preliminary measurements by means of the described ion-spectrometer have been performed within the RPI-IBIS facility operated at about 50 kJ, with the pulsed injection of a working gas. The paper presents results of the detailed measurements of energy distributions of di(r)erent ion-species, i.e. protons, deuterons and nitrogen ions, within the energy range from about 50 keV to about 300 keV.

Control Over Charge Separation in Phthalocyanine−Anthraquinone Conjugates as a Function of the Aggregation Status

We have prepared three isomeric donor-acceptor systems, in which two phthalocyanine (Pc) units have been attached to the 1-,5- (1a), 1-,8- (1b), or 2-,6- (1c) positions of a central anthraquinone (AQ) moiety, leading to packed (1b) or extended (1a and 1c) topologies. The electronic interactions between the donor and the acceptor in the ground state or in the excited states have been studied by different electrochemical and photophysical techniques. Due to the markedly different topologies, we have been able to modify these interactions at the intramolecular level and, by a proper choice of the solvent environment, at the intermolecular level within aggregates. In triad 1b, the ZnPc units are forced to pi-stack cofacially and out of the plane of the AQ ring. Consequently, this molecule shows strong inter-Pc interactions that give rise to intramolecular excitonic coupling but a relatively small electronic communication with the AQ acceptor through the vinyl spacers. On the contrary, the 1-,5- or 2-,6-connections of triads 1a and 1c allow for an efficient pi-conjugation between the active units that extends over the entire planar system. These two molecules tend to aggregate in aromatic solvents by pi-pi stacking, giving rise to J-type oligomers. Photoexcitation of the Pc units of 1a-c results in the formation of the Pc.+-AQ.- charge transfer state. We have demonstrated that the kinetics of these electron transfer reactions is greatly dependent on the aggregation status of the triads.

New Donor–Acceptor Materials Based on Random Polynorbornenes Bearing Pendant Phthalocyanine and Fullerene Units

New donor-acceptor materials based on a polynorbornene framework to which both phthalocyanine and C60 electroactive pendant units are randomly attached have been prepared in good yield by ring-opening-metathesis polymerization (ROMP) in the presence of a Grubbs catalyst. A structurally related phthalocyanine homopolymer was also synthesized for comparison. A remarkable fluorescence quenching was observed in the homopolymer and accounts for PcPc interactions along the polymeric framework. As expected, the fluorescence quenching increases in the case of the polynorbornenes containing both Pc and C60 units owing to photoinduced electron transfer, which was further confirmed by transient absorption spectroscopy. Finally, preliminary solar cell devices made of one of the copolymers were constructed.

Transfusion practice in massively bleeding patients: time for a change?

We identified some fatal cases where massively bleeding patients received inadequate transfusion therapy. The aim of this study was to review and evaluate the transfusion practice in acutely multitransfused patients. Patients receiving > 10 units of red blood cells (RBC) within 24 h of admission and 30 blood components within 7 days of admission were reviewed. Thirty-nine patients were identified, 13 of whom were inadequately transfused (IT) and had a higher mortality (12/13) than adequately transfused (AT) patients 13/26 (P = 0.013). Ten of 13 IT patients developed a microvascular bleed compared to four of 26 in the AT group (P = 0.001) and had a lower platelet count upon arrival at the intensive care unit (40 x 10(9)/l vs. 80 x 10(9)/l, P = 0.024). An early balanced transfusion therapy is vital in massively bleeding patients, and a pro-active approach from the blood bank is warranted. We have introduced an acute transfusion package (ATP) consisting of 5 RBC, 5 FFP and 2 PC units, indicated in massively bleeding patients, securing a balanced transfusion therapy.

No for Reagent Strips as a Predictor of Bacterial Contamination in Platelet Concentrates!

Public awareness has long focused on the risks of the transmission of viral agents through blood product transfusion this risk, however, pales in comparison to the less publicized danger associated with the transfusion of blood products contaminated with bacteria, in particular, platelet concentrates [PC]. It has been suggested that measuring the pH and glucose level of PC using reagent strips can serve as a suitable measure for detection of any bacterial contamination. A total of 500 random donor platelets pool units with a shelf life of 6 days were screened for bacterial contamination using urine reagent strips [Combi-Screen, Analyticon, Germany]. Glucose and pH were measured; results were compared with quantitative culture using aerobic blood culture bottles. A glucose level less than 250 mg per dL and/or a pH value of less than 7.0 was considered positive indication for bacterial contamination. Of the 500 PCs that were screened using reagent strips, 257 had a pH value of less than 7.0 [51.4%] with one sample only showing a concomitant hypoglycemia with glucose level of 100 mg/dl while none showed bacteria growth on culture. On the other hand 4 bacterially contaminated PC units with colony count >105 CFU/ml were not detected by reagent strips, as they were of normal ph and glucose levels, this was associated with a sensitivity and specificity of 0% and 51.8%, respectively. So the use of reagent strips for the detection of bacterially contaminated platelets should be reconsidered.