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Aircraft monitoring systems offer enhanced safety, reliability, reduced maintenance cost and improved overall flight efficiency. Advancements in wireless sensor networks (WSN) are enabling unprecedented data acquisition functionalities, but their applicability is restricted by power limitations, as batteries require replacement or recharging and wired power adds weight and detracts from the benefits of wireless technology. In this paper, an energy autonomous WSN is presented for monitoring the structural current in aircraft structures. A hybrid inductive/hall sensing concept is introduced demonstrating 0.5 A resolution, < 2% accuracy and frequency independence, for a 5 A – 100 A RMS, DC-800 Hz current and frequency range, with 35 mW active power consumption. An inductive energy harvesting power supply with magnetic flux funnelling, reactance compensation and supercapacitor storage is demonstrated to provide 0.16 mW of continuous power from the 65 μT RMS field of a 20 A RMS, 360 Hz structural current. A low-power sensor node platform with a custom multi-mode duty cycling network protocol is developed, offering cold starting network association and data acquisition/transmission functionality at 50 μW and 70 μW average power respectively. WSN level operation for 1 minute for every 8 minutes of energy harvesting is demonstrated. The proposed system offers a unique energy autonomous WSN platform for aircraft monitoring.

Polonium isotopes are considered the most hazardous radionuclides produced during the operation of accelerator driven systems (ADS) when lead–bismuth eutectic (LBE) is used as the reactor coolant and as the spallation target material. In this work the use of gold surfaces for capturing polonium from the cover gas of the ADS reactor was studied by thermochromatography. The results show that gaseous monoatomic polonium, formed in dry hydrogen, is adsorbed on gold at 1058 K. Its adsorption enthalpy was calculated as –250±7 kJ mol−1, using a Monte Carlo simulation code. Highly volatile polonium species that were observed in similar experiments in fused silica columns in the presence of moisture in both inert and reducing gas were not detected in the experiments studying adsorption on gold surfaces. PoO2 is formed in both dry and moist oxygen, and its interaction with gold is characterized by transport reactions. The interaction of bismuth, present in large amounts in the atmosphere of the ADS, with gold was also evaluated. It was found that bismuth has a higher affinity for gold, compared to polonium, in an inert, reducing, and oxidizing atmosphere. This fact must be considered when using gold as a material for filtering polonium in the cover gas of ADS.

This work presents the results obtained from studying the interaction between polonium compounds formed in different atmospheres and platinum, palladium and silver surfaces obtained by thermochromatography. These results are of crucial importance for the design of cover gas filter systems for lead-bismuth eutectic (LBE)-based nuclear facilities such as accelerator driven systems (ADS). The results obtained from studying the interaction of polonium and platinum under inert atmosphere and reducing atmospheres with and without addition of moisture show that polonium is deposited at temperatures between 993 and 1221 K, with adsorption enthalpies ranging from –235 to –291 kJ mol−1, indicating a very strong adsorption of the polonium species present on platinum surfaces. The interaction between polonium and silver was investigated using purified inert, reducing and oxidizing carrier gases. Results show a deposition temperature between 867 and 990 K, with adsorption enthalpies ranging from –205 to –234 kJ mol−1. The interaction of polonium and palladium was studied in purified helium and purified hydrogen. For both conditions a deposition temperature of 1221 K was observed corresponding to an adsorption enthalpy of –340 kJ mol−1. No highly volatile polonium species was formed at any of the applied experimental conditions.

The adsorption behavior of 197Hg and 183–185Hg on red amorphous selenium (red a-Se) and trigonal selenium (t-Se) was investigated experimentally by off-line and on-line gas chromatographic methods, in preparation of a sensitive chemical separation and characterization of the transactinides copernicium (Cn, Z = 112) and flerovium (Fl, Z = 114). Monte-Carlo simulations of a diffusion controlled deposition were in good agreement with the experimental results, assuming as interaction limits −ΔH ads red a-Se (Hg) > 85 kJ/mol, and −ΔH ads t-Se (Hg)

Previously reported preparation method for Pd-based intermetallic targets (Usoltsev, et al., 2012) [1] has been successfully applied for producing two stationary 243Am/Pd targets. Both targets have been irradiated at the U-400 cyclotron at Flerov Laboratory of Nuclear Reactions Dubna (Russian Federation) using high intensity beams (up to 0.83 μApart) of 48Ca18+. Alpha-particle spectroscopy and light microscopy allowed for a comprehensive characterization of the intermetallic targets before and after irradiation. A natNd/Pd intermetallic target and a solely electroplated 243Am/Ti target were similarly investigated for comparison.

The thermal release rate of nuclear reaction products was investigated in offline annealing experiments. This work was motivated by the search for a high melting catcher material for recoiling products from heavy ion induced nuclear fusion reactions. Polycrystalline refractory metal foils of Ni Y Zr Nb Mo Hf W and Re were investigated as catcher metals. Diffusion data for various tracer/host combinations were deduced from the measured release rates. This work focuses on the diffusion and the release rate of volatile p elements from row 5 and 6 of the periodic table as lighter homologues of the superheavy elements with Z = 113 to be studied in future experiments. A massive radiation damage enhancement of the diffusion velocity was observed. Diffusion trends have been established along the groups and rows of the periodic table based on the dependence of diffusion velocity on atomic sizes. © 2013 Elsevier Ltd. All rights reserved.

A new method of intermetallic target preparation is described. Based on the molecular plating technique followed by “coupled reduction”, this method allows producing stable and homogeneous metallic targets for high intensity irradiations. In the first step, the target material is electroplated on a noble metal surface, ensuring homogeneous distribution of the desired element on the target backing. In the second step, the foil with the plated material is heated in a hydrogen flow. Due to the formation of an intermetallic compound with the noble metal support, reduction of the target material with hydrogen at high temperatures becomes thermodynamically possible. Nitrates of all six investigated elements (U, Th, Am, Gd, Nd, and Eu) were electroplated with excellent yields on Pd backing foils by the molecular plating technique and completely reduced in hydrogen atmosphere. A homogeneous distribution of the target material over the whole thickness of the Pd foil was observed suggesting a pronounced diffusion of the reduced metals into the backing material already during the reduction process. A first test irradiation experiment with a thin 3.5 μm U/Pd intermetallic target is described.

The radionuclide-generator based access to radiopharmaceutical isotopes represents a valuable alternative to directly produced isotopes at particle accelerators or nuclear reactors. The44Ti based generator is of increasing interest for the delivery of PET-radiopharmaceutical isotopes used for imaging. The product of this generator44Sc represents with its 3.97 h half-life and 94.3% positron branching [1] a very promising candidate for labeling PET radiopharmaceuticals. The long half-life of 58.9±0.3 y [2] of the44Ti assures a constant and long lasting production of the daughter nuclide.Here we present a gas phase separation method of scandium from titaniumviathermal release in vacuum. Titanium foils were irradiated with40Ar to produce scandium in multi-nucleon transfer reactions. Another production reaction used was the irradiation of titanium by neutrons from the SINQ neutron source at the Paul Scherrer Institute (PSI).The titanium metal foils containing44mSc and46Sc were heated up for time periods of 15 and 60 min to temperatures between 900 °C and 1500 °C in vacuum. Thus, release properties of scandium from titanium under these conditions were studied. The released scandium was collected on tantalum foils and could be rinsed of with concentrated nitric acid resulting in carrier free scandium nitrate solutions. From the experimental results optimum release conditions are suggested.

The chemical investigation of E113 is likely to become soon feasible. The determination of chemical properties of carrier-free amounts of the lighter homologues of element 113, especially indium and thallium, allows designing experimental set-ups and selecting experimental conditions suitable for performing these studies. Here, we present investigations of the interaction of indium species with quartz and gold surfaces. Deposition temperatures as well as enthalpies of adsorption were determined for indiumTdep=739±20 °C (−ΔHads(In)=227±10 kJ mol−1) and for indium hydroxideTdep=250±20 °C (−ΔHads(InOH)= 124±10 kJ mol−1) respectively, on quartz. In case of adsorption of indium on a gold surface only a lower limit of the deposition temperature was establishedTdep>980 °C (−ΔHads(In)≥315±10 kJ mol−1). Investigations of macroscopic amounts of indium in thermosublimation experiments at similar experimental conditions were instrumental to establish a tentative speciation of the observed indium species.

Currently, gas phase chemistry experiments with heaviest elements are usually performed with the gas-jet technique with the disadvantage that all reaction products are collected in a gas-filled thermalisation chamber adjacent to the target. The incorporation of a physical preseparation device between target and collection chamber opens up the perspective to perform new chemical studies. But this approach requires detailed knowledge of the stopping force (STF) of the heaviest elements in various materials. Measurements of the energy loss of mercury (Hg), radon (Rn), and nobelium (No) in Mylar and argon (Ar) were performed at low kinetic energies of around (40–270) keV per nucleon. The experimentally obtained values were compared with STF calculations of the commonly used program for calculating stopping and ranges of ions in matter (SRIM). Using the obtained data points an extrapolation of the STF up to element 114, eka-lead, in the same stopping media was carried out. These estimations were applied to design and to perform a first chemical experiment with a superheavy element behind a physical preseparator using the nuclear fusion reaction 244Pu(48Ca; 3n)289114. One decay chain assigned to an atom of 285112, the α-decay product of 289114, was observed.

Summary In clinical practice, intravenous immunoglobulin therapy (IVIG) is used in the management of a wide variety of medical conditions. Observational studies examining IVIG use in routine clinical practice are therefore an important means of validating findings from more strictly randomized controlled trials of patients with specific conditions. In this observational study, we examined the tolerability of a high-concentration (12%) ready-to-use liquid IVIG (Redimune® NF Liquid) when used in the standard management of a diverse range of conditions (including primary immunodeficiency diseases, neurology conditions, oncology conditions and immune thrombocytopaenic purpura). IVIG regimen and dose were selected by the physician based on the summary of product characteristics. During the study, 193 infusions were administered to 51 patients in 153 infusion cycles (per infusion cycle: one to five infusions; mean dose, 347·6 mg/kg; mean duration, 202·4 min). The mean maximum infusion rate per cycle was 2·9 mg/kg/min, demonstrating that the infusion rate was often higher than that recommended in the summary of product characteristics. Redimune® NF Liquid was well tolerated: there were 36 adverse reactions (at least probably associated with IVIG) in 10 patients (19·6% of sample, 0·24 per infusion cycle, 0·19 per infusion). The most common adverse reaction was headache (50% of reactions), followed by chills (13·8%). Most reactions (69%) were mild and there were no serious or unexpected reactions. In conclusion, in routine clinical practice involving patients with many different conditions, Redimune® NF Liquid was well tolerated by the majority of patients.

Two gas phase adsorption chemistry experiments aimed at the chemical characterization of element 112 using its isotope 283 112 have been performed at the Flerov Laboratory for Nuclear Reactions (FLNR) Dubna, Russia. The applied Insitu-Volatilization and On-line Detection (IVO) technique is a thermochromatographic system combining the determination of the deposition temperature of volatile elements on a surface along a temperature gradient with an efficient detection of the deposited species by event-by-event alpha and SF-fragment spectroscopy. Two possibilities to produce the isotope 283 112 were used: 1.) the direct production reaction 238 U( 48 Ca,3n) 283 112; 2.) the reaction 242 Pu( 48 Ca,3n), where the primary product 287 114, decays via alpha emission to 283 112 with a half-life of 0.5 s. The chemistry experiments were aimed at a chemical identification of 283 112 and an independent confirmation of its decay properties. In the direct reaction no decays related to 283 112 were observed. However, two decay chains unambiguously attributed to the decay of 283 112 were observed using the second production path. Previously reported observation of 283 112 and 279 Ds and their decay properties were confirmed. From its thermochromatorgaphic deposition first thermochemical data were deduced for element 112, unveiling it as a typical group 12 element.

Element 112 was discovered at the Heavy Ion Research Laboratory in Darmstadt, Germany in 1996. A decade on, and some of its chemical properties have now been determined. Irradiation of plutonium-242 with intense calcium-48 beams for three weeks produced two atoms of element 112 (not yet officially named, but commonly called ununbium), and that's enough to do some chemistry on if you are quick. Chemically ununbium behaves as a typical element of the group 12 in the periodic table (which it shares with Zn, Cd and Hg). It is very volatile and forms a metallic bond with a gold surface. An experiment has scrutinized two atoms of element 112, finding that it is very volatile and forms a metallic bond with a gold surface. These characteristics establish element 112 as a typical element of group 12. The heaviest elements to have been chemically characterized are seaborgium1 (element 106), bohrium2 (element 107) and hassium3 (element 108). All three behave according to their respective positions in groups 6, 7 and 8 of the periodic table, which arranges elements according to their outermost electrons and hence their chemical properties. However, the chemical characterization results are not trivial: relativistic effects on the electronic structure of the heaviest elements can strongly influence chemical properties4,5,6. The next heavy element targeted for chemical characterization is element 112; its closed-shell electronic structure with a filled outer s orbital suggests that it may be particularly susceptible to strong deviations from the chemical property trends expected within group 12. Indeed, first experiments concluded that element 112 does not behave like its lighter homologue mercury7,8,9. However, the production and identification methods10,11 used cast doubt on the validity of this result. Here we report a more reliable chemical characterization of element 112, involving the production of two atoms of 283112 through the alpha decay of the short-lived 287114 (which itself forms in the nuclear fusion reaction12 of 48Ca with 242Pu) and the adsorption of the two atoms on a gold surface. By directly comparing the adsorption characteristics of 283112 to that of mercury and the noble gas radon, we find that element 112 is very volatile and, unlike radon, reveals a metallic interaction with the gold surface. These adsorption characteristics establish element 112 as a typical element of group 12, and its successful production unambiguously establishes the approach to the island of stability of superheavy elements through 48Ca-induced nuclear fusion reactions with actinides.

Summary Two experiments aiming at the chemical investigation of element 112 produced in the heavy ion induced nuclear fusion reaction of 48Ca with 238U were performed at the Gesellschaft für Schwerionenforschung (GSI), Darmstadt, Germany. Both experiments were designed to determine the adsorption enthalpy of element 112 on a gold surface using a thermochromatography setup. The temperature range covered in the thermochromatography experiments allowed the adsorption of Hg at about 35 °C and of Rn at about -180 °C. Reports from the Flerov Laboratory for Nuclear Reactions (FLNR), Dubna, Russia claim production of a 5-min spontaneous fission (SF) activity assigned to 283112 for the 238U(48Ca,3n) 283112 reaction. Hence, Experiment I was designed to detect spontaneously fissioning (SF) isotopes of element 112 with half-lives (t 1/2) longer than about 20 s. 11 high-energy events were detected. 7 events exhibit a deposition pattern resembling a chromatographic peak in the vicinity of Rn deposition. However, the energy of the events observed in Experiment I was lower than expected for a SF-decay of 283112. Therefore, these events could not be unambiguously attributed to the decay of 283112. In contradiction with earlier publications newer reports from FLNR Dubna claim that 283112 decays by α-particle emission (E α = 9.5 MeV) with t 1/2 = 4 s followed by a SF-decay of 279Ds (t 1/2 = 0.2 s). Therefore, Experiment II was designed to be sensitive to both claimed decay properties of 283112. However, during this experiment neither short α-SF correlations nor SF coincidences were detected. The conclusion is that 283112 was not unambiguously detected, neither in Experiment I nor in Experiment II.

In preparation for the experimental investigation of chemical properties of element 112 model studies were conducted based on the assumed similarity of element 112 to either the noble gas Rn or the transition metal Hg, its supposed lighter homologue in group 12. The adsorption behavior of elemental Hg on the transition metals Ag, Au, Ni, Pd, and Pt were investigated experimentally by off-line gas thermochromatography. The deduced adsorption data of Hg were compared with new values calculated using the Eichler–Miedema model. The observed sequence of increasing Hg-metal-interactions for Ag < Ni < Au < Pd < Pt confirms the predicted trend. The only exception was Pd, on which Hg was calculated to adsorb at a higher temperature than on Pt. Difficulties to obtain reproducible clean surfaces of Ag, Ni, Pd, and Pt led to the choice of Au as the best metal surface suitable to adsorb Hg. For fast on-line gas thermochromatography studies on metallic surfaces a new set-up was developed based on the In-situ Volatilization and On-line detection technique (IVO). This set-up was tested in on-line thermochromatographic investigations with short-lived Hg isotopes and 219Rn, using Au or Pd as stationary surfaces. An overall efficiency of about 60% and a transportation time less than 25 s was determined for this newly designed IVO. A separation factor of more than 106 was estimated for non-volatile species.

Carrier-free short-lived nuclides are employed in many different fields of modern nuclear chemistry. The two main production strategies are either thermal neutron-induced fission of 235U or 239Pu at nuclear reactors or spallation neutron sources or charged particle-induced nuclear reactions at accelerator facilities. An alternative method is to use a spontaneously fissioning nuclide. A facility applying this technique (“Miss Piggy”) was built at the University of Berne (Switzerland). Californium-252 (252Cf), which has a 3% fission branch and a half-life of 2.645 a, is used for the production of short-lived fission products that are stopped in an adjacent recoil chamber. Short-lived nuclides are transported out of the recoil chamber using the well-known gas-jet technique. Over 100 nuclides have been identified so far and used in different applications. Since such a device does not require any large facility and is easy to operate it serves well the needs of typical university laboratories.

In bombardments of 248Cm with 143.7-146.8 MeV 26Mg ions the nuclides 269Hs and presumably 270Hs were produced. After chemical isolation, Hs atoms were identified by observing genetically linked nuclear-decay chains. Three chains originating from 269Hs confirmed the decay properties observed previously in the decay of 277112. Two chains exhibited the characteristics expected for the new nuclide 270Hs, which was predicted to be a deformed ”doubly magic” nucleus. From the measured $E_\alpha =9.16^{+0.07}_{-0.03}$ MeV an $\alpha$ -decay half-life of 3.6+0.8 -1.4 s was estimated.

Recently, the first successful chemical investigation of element 108, hassium (Hs) has been reported [1]. Based on 7 detected atoms, Hs was shown to form a higly volatile oxide, most probably HsO4. Therefore it behaves similarly to Os, which is known to form highly volatile OsO4. The enthalpies of adsorption-ΔHa O(T) of the compounds on silicon nitride were evaluated as (46±2) kJ/mol for HsO4, compared to (39±1) kJ/mol for OsO4 under identical experimental conditions. Hs should therefore be considered as a member of group 8 of the periodic table.

A new gaschromatographic separation system to rapidly isolate heavy ion reaction products in the form of highly volatile species is described. Reaction products recoiling from the target are stopped in a gas volume and converted in situ to volatile species, which are swept by the carrier gas to a chromatography column. Species that are volatile under the given conditions pass through the column. In a cluster chamber, which is directly attached to the exit of the column, the isolated volatile species are chemically adsorbed to the surface of aerosol particles and transported to an on-line detection system. The whole set-up was tested using short-lived osmium (Os) and mercury (Hg) nuclides produced in heavy ion reactions to model future chemical studies with hassium (Hs, Z =108) and element 112. By varying the temperature of the isothermal section of the chromatography column between room temperature and −80°C, yield measurements of given species can be conducted, yielding information about the volatility of the investigated species.

Seaborgium (Sg; element 106) was studied in comparison with tungsten in the O2-H2O(g)/SiO2(s)-system using high temperature on-line isothermal gas chromatography. The 21-s nuclide266Sg was produced in the248Cm+22Ne reaction at a beam energy of 119 MeV. The reaction products were continuously transported by a He(MoO3)-jet to the chromatography apparatus HITGAS. Group 6 element oxide hydroxide molecules volatile at temperatures above 1000 K were formed at 1325 K by adding humid oxygen as reactive gas.266Sg was unambiguously detected after gas chromatographic separation by measuring266Sg-262Rf mother-daughter α-sf correlations. The experimental results demonstrate the volatility of Sg in humid oxygen, presumably as Sg oxide hydroxide, a behavior typical for both U(VI) and the group 6 elements.

The chloride and oxychloride chemistry of the group 7 elements Tc and Re was investigated in order to develop an experimental approach to a gas chemical characterisation of bohrium (Bh, element 107). In thermochromatography experiments with trace amounts of101,104Tc and183,184Re the formation of one volatile compound was observed in O2/HCl containing carrier gas, which was attributed to MO3Cl (M = Tc, Re). From the measured deposition temperatures the adsorption enthalpies on quartz surfaces ΔHads(TcO3Cl) = -51 ± 3 kJ/mol and ΔHads(ReO3Cl) = -62 ± 3 kJ/mol were evaluated. The sublimation enthalpies were derived using an empirical correlation between Δ Hadsand ΔHsubl: ΔHsubl(TcO3Cl) = 49±10 kJ/mol and ΔHsubl(ReO3Cl) = 67±10 kJ/mol. A fast gas chemical separation technique for highly volatile compounds of short-lived isotopes based on isothermal gas solid adsorption chromatography (OLGA-principle) was developed. With a modified OLGA device, model studies with the short-lived nuclides106,107,108Tc and169,170,174,176Re were carried out in preparation of an experimental gas chemical investigation of bohrium (Bh, element 107). Separation times of less than 3 s were achieved. A good separation of the oxychlorides of group 7 elements from chloride and oxychloride compounds of152-155Er,151-154Ho (as models for actinide elements),98-101Nb,99-102Zr (as models for light transactinide elements),218Po, and214Bi was accomplished in this chemical system.

Polluted air masses are characterized by high concentrations of oxidized nitrogen compounds which are involved in photochemical smog and ozone formation. The OH radical is a key species in these oxidation processes. The photolysis of nitrous acid (HNO2), in the morning, leads to the direct formation of the OH radical and may therefore contribute significantly to the initiation of the daytime photochemistry in the polluted planetary boundary layer. But the formation of nitrous acid remains poorly understood: experimental studies imply that a suggested heterogeneous formation process involving NO2 is not efficient enough to explain the observed night-time build-up of HNO2 in polluted air masses1. Here we describe kinetic investigations which indicate that the heterogeneous production of HNO2 from NO2 on suspended soot particles proceeds 105 to 107 times faster than on previously studied surfaces. We therefore propose that the interaction between NO2 and soot particles may account for the high concentrations of HNO2 in air masses where combustion sources contribute to air pollution by soot and NOx emissions. We believe that the observed HNO2 formation results from the reduction of NO2 in the presence of water by C–O and C–H groups in the soot. Although prolonged exposure to oxidizing agents in the atmosphere is likely to affect the chemical activity of these groups, our observations nevertheless suggest that fresh soot may have a considerable effect on the chemical reactions occurring in polluted air.

On the basis of thermodynamic extrapolations, the first transactinide element 104 (Rf=rutherfordium 1 ) is expected to form volatile tetrachlorides of lower volatility than those of the homologous element Hf. In contrast, relativistic calculations predict a higher volatility of RfCl 4 compared to HfCl 4 . The nuclides 261 Rf and 165 Hf, with identical half-lives of 78 s, were simultaneously produced at the U-400 cyclotron of the Flerov Laboratory of Nuclear Reactions (FLNR), Dubna, Russia, by bombarding a mixed 248 Cm/ 152 Gd target with 18 O ions. With the on-line gas chemistry apparatus (OLGA), the retention behavior of volatile Rf- and Hf-chloride in a quartz chromatography column was investigated. The results showed that Rf forms chlorides of higher volatility than those of Hf, in agreement with relativistic calculations. In addition, the behavior of element 104 was investigated in chlorinating, oxygen containing carrier gas, in order to answer the question whether a volatile compound of the form RfOCl 2 exists. The results of our experiments give strong evidence for a transport reaction mechanism where RfOCl 2 exists only in the condensed phase and not in the gas phase.

The retention behavior of volatile chlorides and oxychlorides of short-lived isotopes of group 5 elements Nb and 105 (Ha = hahnium) in quartz columns was studied using on-line iso-thermal gas chromatography. The 15-s "8Nb was produced from a 215U-fission target at a reactor neutron beam line and 34-s 262Ha in fusion reactions of '80 + 249Bk. The reaction products were continuously and rapidly transported to the chromatography apparatus with a carbon aerosol gas-jet system using He as carrier gas. Volatile chloride molecules were formed in a 900°C reaction oven by adding HCl as reactive gas. Depending on trace amounts of 02 in the system, either the pentachlorides or the oxytrichlorides, or a mixture thereof, were formed. The isotopes "»Nb and 262Ha were unambiguously identified after gas chromatographic separation by measuring the characteristic y-lines of "gNb and by registering 262Ha-25*Lr mother-daughter a-a correlations as well as spontaneous fission decays, respectively. The adsorption enthalpies of the investigated species on quartz surfaces were determined by analyzing the measured retention curves with a Monte Carlo model. Using an empirical correlation, the adsorption enthalpies were converted to sublimation enthalpies. The sublimation enthalpies of 95 ± 16 kJ-mol"1 and 124± 16 kJ · mol"' determined for NbCls and NbOCl3, respectively, were in good agreement with literature data. In experiments with Ha-chlorides a yield curve with two components was observed. Sublimation enthalpies of ≥ 120 kJ mol-1 and 152 ±18 kJ-mol"' were estimated for HaCl5 and HaOCl3, respectively. The estimated sublimation enthalpies were compared with theoretical predictions from relativistic calculations and with empirical extrapolations of chemical properties. In agreement with empirical extrapolations, a lower volatility was found for HaOCl3 than for NbOCl3.

The heterogeneous reaction of NO2 with different carbon aerosol particles was investigated in situ. The NO2 was labeled with the β+-emitter 13N (half-life 10.0 min) which allowed application of NO2 at very low concentrations. The carbon aerosol was either produced by a spark discharge generator using graphite electrodes or by a brush generator resuspending commercial soot material. Monodisperse size cuts between 50- and 490-nm diameter were selected and mixed with the 13NO2. After a defined reaction time, the different reaction products were separated by means of selective traps and detected on-line by γ-spectrometry. A sticking coefficient for chemisorption of NO2 between 0.3 × 10-4 and 4.0 × 10-4 and a rate constant for the reduction of adsorbed NO2 to NO(g) between 4.0 × 10-4 and 9.4 × 10-4 s-1 were determined for both aerosols. The sticking coefficient obtained in this study in situ with aerosol particles is 2 orders of magnitudes smaller than the uptake coefficient recently reported with bulk carbon ...

In recent years gas-phase chemical studies assisted by physical pre-separation allowed for the investigation of fragile single molecular species by gas-phase chromatography. The latest success with the heaviest group 6 transactinide seaborgium is highlighted. The formation of a very volatile hexacarbonyl compound Sg(CO)6 was observed similarly to its lighter homologues molybdenum and tungsten. The interactions of these gaseous carbonyl complex compounds with quartz surfaces were investigated by thermochromatography. Second-generation experiments are under way to investigate the intramolecular bond between the central metal atom of the complexes and the ligands addressing the influence of relativistic effects in the heaviest compounds. Our contribution comprises some aspects of the ongoing challenging experiments as well as an outlook towards other interesting compounds related to volatile complex compounds in the gas phase.

The antiemetic efficacy and safety of granisetron (40 μg/kg), a selective and potent 5-hydroxytryptamine (serotonin) antagonist, was compared with that of metoclopramide (7 mg/kg) plus dexamethasone (12 mg) in patients receiving fractionated chemotherapy. Patients receiving cisplatin at doses of at least 15 mg/m2 or etoposide at least 120 mg/m2 or ifosfamide at least 1.2 g/m2 on each of 5 consecutive days were eligible. A total of 143 patients received granisetron and 141 received the comparator regimen. The 5-day complete response rate (no vomiting, no worse than mild nausea) for granisetron (46.8%) was equivalent to that for metoclopramide plus dexamethasone (43.9%). The overall 5-day response profile was superior for granisetron (P=0.013) because of fewer failures in this group. The overall incidence of adverse experiences was significantly lower in the granisetron group (60.8% versus 77.3%,P=0.003). Headache and constipation, more prevalent in the granisetron group, are recognized side-effects of serotonin antagonists. Extrapyramidal syndrome, not seen in any granisetron patients, occurred in 20.6% of comparator patients (P

The arrangement of the chemical elements in the periodic table highlights resemblances in chemical properties, which reflect the elements’ electronic structure. For the heaviest elements, however, deviations in the periodicity of chemical properties are expected1,2,3: electrons in orbitals with a high probability density near the nucleus are accelerated by the large nuclear charges to relativistic velocities, which increase their binding energies and cause orbital contraction. This leads to more efficient screening of the nuclear charge and corresponding destabilization of the outer d and f orbitals: it is these changes that can give rise to unexpected chemical properties. The synthesis of increasingly heavy elements4,5,6, now including that of elements 114, 116 and 118, allows the investigation of this effect, provided sufficiently long-lived isotopes for chemical characterization are available7. In the case of elements 104 and 105, for example, relativistic effects interrupt characteristic trends in the chemical properties of the elements constituting the corresponding columns of the periodic table8, whereas element 106 behaves in accordance with the expected periodicity9,10,11,12. Here we report the chemical separation and characterization of six atoms of element 107 (bohrium, Bh), in the form of its oxychloride. We find that this compound is less volatile than the oxychlorides of the lighter elements of group VII, thus confirming relativistic calculations13 that predict the behaviour of bohrium, like that of element 106, to coincide with that expected on the basis of its position in the periodic table.

The production of 283112 in 48Ca induced nuclear reactions was investigated using physical and chemical separation techniques. In the reaction 48Ca on 238U, four events were registered at the SHIP velocity filter. The mean atomic mass of the evaporation residues (EVR)

An original experimental method is presented for measuring the stiffness and displacement characteristics of small size freestanding mechanical elements on actual MEMS devices. This setup allows, using analytic and finite-element method mechanical calculations, the extraction of the elastic modulus of the materials used in such mechanical elements, thus eliminating the need of special integrated test structures. The setup has, respectively, a force and displacement measurement accuracy better than 1 /spl mu/N and 50 nm. Its application is demonstrated by the characterization of a MEMS magnetostatic switch.

A passive magnetostatic sensing MEMS device, similar to a reed switch, having a packaged volume of 2 mm/sup 3/ is described. It is capable of sensing the field of a 1 mm/sup 3/ SmCo magnet at a distance of more than 2 mm. The contact force between the microformed rhodium contact surfaces lies between 10 and 30 /spl mu/N, and contact resistances as low as 2 /spl Omega/ are measured. No contact sticking is observed. The device operation life extends to at least 200,000 cycles when packaged at wafer level with epoxy sealing. The device operation life increases to 100/spl times/10/sup 6/ cycles when measured on bare wafers in argon, showing that these MEMS sensors are intrinsically reliable in spite of the very low contact forces.

The periodic table provides a classification of the chemical properties of the elements. But for the heaviest elements, the transactinides, this role of the periodic table reaches its limits because increasingly strong relativistic effects on the valence electron shells can induce deviations from known trends in chemical properties. In the case of the first two transactinides, elements 104 and 105, relativistic effects do indeed influence their chemical properties, whereas elements 106 and 107 both behave as expected from their position within the periodic table. Here we report the chemical separation and characterization of only seven detected atoms of element 108 (hassium, Hs), which were generated as isotopes (269)Hs (refs 8, 9) and (270)Hs (ref. 10) in the fusion reaction between (26)Mg and (248)Cm. The hassium atoms are immediately oxidized to a highly volatile oxide, presumably HsO(4), for which we determine an enthalpy of adsorption on our detector surface that is comparable to the adsorption enthalpy determined under identical conditions for the osmium oxide OsO(4). These results provide evidence that the chemical properties of hassium and its lighter homologue osmium are similar, thus confirming that hassium exhibits properties as expected from its position in group 8 of the periodic table.

Background To assess the activity and toxicity of 2-chlorodeoxyadenosine (cladribine, CDA) given by subcutaneous bolus injections to patients with hairy cell leukemia (HCL). Patients and methods Sixty-two eligible patients with classic or prolymphocytic HCL (33 non-pretreated patients, 15 patients with relapse after previous treatment, and 14 patients with progressive disease during a treatment other than CDA) were treated with CDA 0.14 mg/kg/day by subcutaneous bolus injections for five consecutive days. Response status was repeatedly assessed according to the Consensus Resolution criteria. Results Complete and partial remissions were seen in 47 (76%) and 13 (21%) patients, respectively, for a response rate of 97%. All responses were achieved with a single treatment course. Most responses occurred early (i.e. within 10 weeks) after start of CDA therapy, but response quality improved during weeks and even months after treatment completion. The median time to treatment failure for all patients was 38 months. Leukopenia was the main toxicity. Granulocyte nadir (median 0.2 × 109/l) was strongly associated with the incidence of infections (P = 0.0013). Non-specific lymphopenia occurred early after CDA treatment, and normal lymphocytes recovered slowly over several months. No significant associations were found between infections and nadir count of lymphocytes or any lymphocyte subpopulation. No opportunistic infections were observed. Conclusions One course of CDA given by subcutaneous bolus injections is very effective in HCL. The subcutaneous administration is more convenient for patients and care providers, and has a similar toxicity profile to continuous intravenous infusion. The subcutaneous administration of CDA is a substantial improvement and should be offered to every patient with HCL requiring treatment with CDA.

Permanent venous access devices (PVAD) are nowadays routinely implanted and used with some morbidity for the oncological treatments. The adequate timing of implantation based on the number of treatments, the survival rate and the complications has not yet been well estimated.A hundred permanent venous access devices placed in oncological patients were followed-up prospectively.No mortality was seen due to the surgical act. A 11% morbidity rate was noted, largely due to infections, with 6 patients needing a second surgery. On average, 6 chemotherapy cycles were done after placing of the permanent venous access device.Due to these results and an average survival rate of 10.7 months, we suggest the placing of a permanent venous access device early in the management of oncological patients requiring chemotherapy cycles, so as to increase the comfort of the patient and to safeguard his peripheral venous system.

Permanent venous access devices allow long-term parenteral treatment under relatively safe and comfortable conditions. Nevertheless, this use is associated with some degree of (particularly infectious) morbidity. 25 permanent access devices were removed surgically in immediate autopsies and cultured. Some half were infected, with a clear prevalence (40%) for Staphylococcus coagulase negative. The results were related to clinical history and compared with the figures and conclusions of other studies. It is proposed that in certain situations cultures of native blood should be carried out more frequently through the permanent venous access, with a view to possible specific targeted antibiotic therapy associated with the heparinized lock.

The pinch off syndrome due to squeezing of the implanted catheter is a rare complication of permanent venous access devices (0.1 to 1% of the cases). The cause is a mechanical catheter's compression in the costo-clavicular space, when implanted too medially in the subclavian vein. In case of lack of venous reflux or injection difficulties, sometimes complicated by local pain, a radiological control must be obtained to demonstrate signs of compression or beginning of fracture. Significant damage to the system is shown be extravasation of radioopaque contrast medium. The suspicion of catheter damage justifies early replacement of the system to avoid right heart or pulmonary artery embolism. The electron microscopic scanning tends to prove that the catheter's rupture is caused by a fatigue process.

Group 6 elements are known to form volatile chlorides and oxychlorides. These compounds are therefore suited for separations with the On-Line Gaschemistry Apparatus OLGA, a device which is able to isolate volatile species at a maximum temperature of 500°C. OLGA has previously been used to study the group 4 and 5 halides. In preparation of experiments with element 106 (Sg = seaborgium), a member of group 6, first, a literature survey on the thermochemical properties of chlorides and oxychlorides of Mo and W as well as of the pseudo-group 6 element U was made. Second, OLGA experiments were per-formed with short-lived isotopes of Mo, W and U, using Cl2, saturated with SOCl2 for chlorination, and different partial pressures of 02. Under such conditions, these elements formed species, which were volatile in quartz chromatography columns at temperatures ≤ 250°C.

The discovery of high hemoglobin and hematocrit values in a patient necessitates the determination of the red blood cell mass in order to confirm the absolute character of the polycythemia. If a true polycythemia is confirmed, its etiology must then be established. The diagnostic approach of polycythemia is presented in this paper. It is illustrated by a case presentation in which a polycythemia secondary to a renal carcinoma is discussed. Erythrocytosis is a classical, albeit rare manifestation of this type of tumor, and has the advantage of allowing early detection. Thus, it permits a prompt treatment plan, thereby improving the prognosis of such a neoplasia. The usefulness of a serum level of erythropoietin (EPO) is subsequently discussed. The diagnostic value of EPO remains controversial because of the overlapping values recorded amongst healthy patients, patients with polycythemia vera and others with secondary polycythemia. Finally, we discuss the presence of substances in paraneoplastic polycythemias whose biological activity is close to that of EPO. However, this molecules of a different structure would not be detected by the radioimmunoassay used to measure erythropoietin level.

The speech of schizophrenics is idiosyncratic, possibly unrelated to thought disorders. Review of relevant literature indicates that schizophrenic speech disorders include: errors in the use of pronouns, articles, verbs and verb tenses, which are neither pointed out or corrected; absence of redundancy, skewering of the meaning of words, faulty establishment of common references with others. Sentences appear disjointed due to improvised vocabulary and the scant use of conjunctions and other linking words or phrases. Speech is slow, trite, and fails to convey information proportionate to speech production. Discourse is self-centered and the needs of others are ignored. In general, schizophrenic speech performance worsens the more ambiguous, intimate or complex the topic.

Assessment of the risk of toxoplasma infection during pregnancy in the female population of the Geneva area, and of the risk of congenital toxoplasmosis, has shown 9 cases of toxoplasmosis for 1000 pregnancies and 3.5 congenital infections for 1000 newborn infants. These results show that the prevalence of toxoplasma infection has been decreasing constantly during the 15 years of study, but that the risk of infection during pregnancy and of congenital infection has remained steady.