Glove Box System Research Articles

A compact multi-chamber setup for degradation and lifetime studies of organic solar cells

A controlled atmosphere setup designed for long-term degradation studies of organic solar cells under illumination is presented. The setup was designed with ease-of-use and compactness in mind and allows for multiple solar cells distributed on four glass substrates to be studied in four different chambers with temperature and atmosphere control. The four chambers are situated at close proximity in the setup thereby allowing the solar cells to be subjected to as uniform an illumination distribution as possible for the given solar simulator employed. The cell substrates serve as the front window and present a tight seal. Hence no illumination correction needs to be performed due to transmission and reflection losses as otherwise seen with test chambers employing a window as a seal. The solar cells in each chamber are continuously and individually electrically monitored under biased conditions by means of a computer controlled multiplexer and source meter. The dimensions of the setup allow it to pass through a mid-size load lock in most common glove box systems allowing for mounting of tested samples under inert conditions. As a demonstration of the applicability of the chamber design, a degradation study of standard P3HT:PCBM solar cells was performed under four different environmental conditions.

Tritium safety consideration in the design of tritium systems for China HCSB and DFLL TBMs

The main goal of an international thermonuclear experimental reactor (ITER) test blanket module (TBM) is to test the feasibility of tritium production and extraction. China has designed two types of TBMs to put in a whole test port, which are the helium-cooled solid breeder (HCSB) TBM and the dual-function lithium lead (DFLL) TBM. A set of common tritium processing systems was designed for the two types of TBMs, including the tritium extraction system (TES), the helium coolant system and the coolant purification system (CPS). Tritium in the TBMs and the ancillary systems should be controlled for the sake of radiological safety. The design of a few key parameters, such as the partial pressures of tritium in the coolant and above the breeder, the flux of carrier gas for tritium extraction, the efficiency of tritium extraction, the selection of the structure material together with the surface coating, etc., depend on the structure of the TBMs and the control of tritium release into the environment. A set of calculation models, based on the tritium mass balance among the TBMs, and different ancillary systems were developed to appraise the tritium safety in the common tritium systems and the Chinese TBMs. A tritium permeation barrier coating on the structure material of some components, a double-wall design for some tritium containers, and the establishment of a glove-box atmosphere detritiation system (GDS) are all necessary to control the release of tritium into the environment.

A New Approach to the Spectral Study of Unstable Radicals and Ions in Solution by the Use of an Inert Gas Glovebox System: Observation and Analysis of the Infrared Spectra of the Radical Anion and Dianion of p-Terphenyl

By using a Fourier-transform infrared spectrometer contained in an inert gas glovebox system (oxygen and water concentrations: <0.1 ppm), high-quality infrared absorption spectra have been observed for the radical anion and dianion of p-terphenyl in tetrahydrofuran solutions. Density functional theory with the B3LYP nonlocal exchange-correlation functional and the 6-311+G** basis set has been used for the calculations of the structures and infrared spectra of the neutral species, radical anion, and dianion of p-terphenyl. The observed infrared spectra of the radical anion and dianion are in good agreement with those calculated by density functional theory. The origin of the strong infrared absorption intensities characteristic of the radical anion and dianion are discussed in terms of changes in electronic structures induced by specific normal vibrations (electron-molecular vibration interaction).

Hypoxia-inducible Factor-1 Mediates Neuronal Expression of the Receptor for Advanced Glycation End Products following Hypoxia/Ischemia

Activation of the receptor for advanced glycation endproducts (RAGE) by its multiple ligands can trigger diverse signaling pathways with injurious or pro-survival consequences. In this study, we show that Rage mRNA and protein levels were stimulated in the mouse brain after experimental stroke and systemic hypoxia. In both cases, RAGE expression was primarily associated with neurons. Activation of RAGE-dependent pathway(s) post-ischemia appears to have a neuroprotective role because mice genetically deficient for RAGE exhibited increased infarct size 24 h after injury. Up-regulation of RAGE expression was also observed in primary neurons subjected to hypoxia or oxygen-glucose deprivation, an in vitro model of ischemia. Treatment of neurons with low concentrations of S100B decreased neuronal death after oxygen-glucose deprivation, and this effect was abolished by a neutralizing antibody against RAGE. Conversely, high concentrations of exogenous S100B had a cytotoxic effect that seems to be RAGE-independent. As an important novel finding, we demonstrate that hypoxic stimulation of RAGE expression is mediated by the transcription factor hypoxia-inducible factor-1. This conclusion is supported by the finding that HIF-1alpha down-regulation by Cre-mediated excision drastically decreased RAGE induction by hypoxia or desferrioxamine. In addition, we showed that the mouse RAGE promoter region contains at least one functional HIF-1 binding site, located upstream of the proposed transcription start site. A luciferase reporter construct containing this RAGE promoter fragment was activated by hypoxia, and mutation at the potential HIF-1 binding site decreased hypoxia-dependent promoter activation. Specific binding of HIF-1 to this putative HRE in hypoxic cells was detected by chromatin immunoprecipitation assay.

Decontamination, Dismantling and Refurbishing of the PETRA Glove Box at the Tritium Laboratory, Karlsruhe

The PETRA facility at the Tritium Laboratory Karlsruhe (TLK) has finished its useful life and the glove box and auxiliary systems are being refurbished. During the lifetime of PETRA the glove box became contaminated with a small amount of tritium but the source has not been positively identified. Removing large redundant components would be hazardous as this would require removing the glove box panels and thus exposing the inner surfaces to moist air which would release tritium. Over several months defined amounts of water have been introduced into the glove box daily which has liberated significant quantities of tritium which has subsequently been absorbed by the in-built tritium retention system. This technique has slowly reduced the tritium liberated at each step. The large components, such as a getter bed, catalyst bed and a permeator, have been detritiated as far as possible in-situ in readiness for disposal once it is safe to remove them from the glove box.

The Closed Tritium Cycle of the Tritium Laboratory Karlsruhe

The Tritium Laboratory Karlsruhe (TLK) was commissioned with tritium in 1994 and since then has continuously improved its infrastructure and has expanded its experimental activities. With a fully closed tritium cycle and the license to handle 40 g of tritium TLK is an almost unique experimental facility. More than 10 glove box systems with a total volume of about 125 m3 are operated to house experiments and infrastructure facilities on an area of more than 1000 m2. Today TLK has about 23 g of tritium on site. The paper describes the closed tritium loop of the TLK infrastructure and its links to different experiments. Some experience gained during operation of TLK is also presented.

Recovery of hydrogen isotopes from inert gas mixtures with a titanium particle bed

A comparative study between experiment and numerical calculations was carried out in order to clarify the characteristics of mass-transfer processes in hydrogenating a titanium particle bed. Hydrogenating rates in the bed were numerically calculated and were fitted to experimental data. The governing equations for the simulation were composed of the equilibrium isotherm of the Ti-H 2 system, the differential material balance equation of hydrogen in the Ti bed and the overall hydrogenating rate equation. The rate equation includes the following three contributions: diffusion in the solid particle, and in the boundary layer of the fluid and the hydriding reaction on surfaces. The comparison showed that the rate-determining step from 673 to 1073 K was the hydriding reaction on particles. An equation for a metal hydride bed was derived for a systematic design of tritium removal from the inert gas atmosphere of a tritium handling glove-box system.

The Handling, Assessment, Transport and Disposal of Tritiated Waste Materials at JET

In November 1991 over 40TBq of tritium was introduced into the JET machine for the first tritium experiment (PTE). This tritium combined with neutron activated material forms the basis of radioactive waste at JET. In order to satisfy regulatory authorities and the operators of the repository to which JET consigns its radioactive waste, JET estimates the level of tritium in each consignment of waste removed from the site. All types of JET radioactive wastes are received for disposal at the Waste Handling Facility (WHF) which features a waste sorting and sampling station, a glove box, a compactor, and packaging and transfer systems. The WHF is operated as a contamination control area with monitored tritium discharges. The waste received includes solid, eg housekeeping waste, machine components and vessel wall tiles; and liquid, eg water, oils and freon containing a unique cocktail of radionuclides consisting of tritium as a contaminant and neutron activated material. The tritium contamination may be in the form of gas, tritiated vapour or tritiated particulate with a specific activity up to 2.5MBq/g. The two main types of tritium monitors used are liquid scintillation counters and ionisation chambers, and samples of various components and materials have now been assessed for tritium. The results so far indicate a widespread of tritium levels from 2Bq/g for cold gas transfer lines to 200kBq/g for in-vessel tiles. General soft housekeeping waste is assessed by a sniffing technique which has a limit of detection corresponding to 120Bq/g. The prospect of the introduction of more tritium during future tritium operations has led to the investigation of improved methods of tritium measurement and of component detritiation to facilitate future waste disposal.

Predominant obligate anaerobes in human periodontal pockets.

This study was carried out to investigate the predominant anaerobic bacteria of periodontal pockets in patients with advanced periodontitis, who had no previous treatment other than supragingival scaling, no history of recent or chronic systemic illness, nor any intake of antibiotics within 6 weeks prior to bacteriological sampling. Care was taken not to ignore tiny-colony-forming anaerobes, by means of a stereoscope and an anaerobic glove box system. Out of 422 (100%) isolates, 380 (90%) were obligate anaerobes, suggesting that the environment in periodontal pockets was anaerobic and favors the growth of obligate anaerobes. Among the 380 obligate anaerobes isolated, strains belonging to Eubacterium (54%) were predominant, and many of them occurred in tiny colonies. The other obligate anaerobes isolated were assigned to Wolinella (9%), unidentified motile rods which resemble Wolinella (7%), Peptostreptococcus (6%), Fusobacterium (5%), Bacteroides (2%; including those reclassified to Prevotella and Porphyromonas) and Selenomonas (0.5%). Among the isolates, 67% were Gram-positive bacteria, including 59% of rods (mostly asaccharolytic Eubacterium), suggesting that these bacteria, particularly strains of the Eubacterium species, may play an important role in etiology of adult periodontitis.

Predominant obligate anaerobes invading the deep layers of root canal dentine

This study was carried out to investigate the presence and types of bacteria invading the deep layers (0.5-2.0 mm from the surface of the root canal wall) of infected dentine of human root canals by sampling with an anaerobic glove box system the split surfaces of eight freshly extracted teeth. More bacteria were recovered after incubation in an anaerobic glove box than after aerobic incubation in air with 30 per cent CO2. Out of 256 predominant bacterial isolated, 205 isolates (80 per cent) were obligate anaerobes. These findings suggest that the environment of deep layers of endodontic dentinal lesions is anaerobic and favours the growth of anaerobes. Among the obligate anaerobic isolates, strains belonging to Lactobacillus (30 per cent) and Streptococcus (13 per cent) were predominant, followed by Propionibacterium (9 per cent). No strains of obligate anaerobic Gram-negative rods were isolated. The microflora of deep layers of infected root dentine is somewhat similar to that of the deep layers of carious lesions in coronal dentine.

A New Glove-Box System for a High-Pressure Tritium Pump

A new glove-box system that was designed around a high-pressure tritium pump is described. The system incorporates new containment ideas such as “burpler” passive pressure controls, valves that can be turned from outside the box, inflatable door seals, ferro-fluidic motor-shaft seals, and rapid box-to-hood conversion during cryostaging. Currently under construction, the system will contain nine separate sections with automatic pressure-balancing and venting systems.

Predominant microorganisms of plaque on complete dentures

The aim of this study is to clarify the microbial constitution of denture plaque with the adoption of the anaerobic glove box system. Anaerobic incubation of the samples taken from five edentulous patients (74-80 yr-old) always gave a higher recovery than aerobic one, suggesting that conditions in the plaque were anaerobic. Of total 185 isolates, 90 (49%) were obligate anaerobes, and the predominant bacteria were among Veillonella (23%), Bifidobacterium (7%), Lactobacillus (5%), Actinomyces (5%) and Eubacterium (3%). Among facultative isolates (51%), Streptococcus (31%) and Lactobacillus(16%) were common. No strains of Candida were isolated. The bacterial composition of denture plaque was somewhat different from that of plaque on teeth.

Corrosion of stainless steel in flowing PbLi eutectic

The corrosion of the steel AISI 304 in a flowing lithium-lead environment is studied in a loop which is equipped with an electromagnetic pump and flow meter. The loop is integrated in a dry-argon glove box system. The tubes of the loop are of austenitic steel AISI 316 Ti, and the whole circuit contains about 3 l of the molten metal. The pre-fabricated alloy Pb-17 at% Li delivered in solid bars is analyzed by chemical methods and by measurement of the melting point. The internal heating rod of 3 kW power heats the liquid metal to the test temperature of 420°C, the flow velocity is within the range 10–20 cm/s. The eutectic does not dissolve measurable amounts of the steel elements, and oxygen is in the < 10 −3 wt% level. The corrosion effects after an exposure of up to 5750 h are evaluated. The weight loss of the steel specimens interferes with the formation of a lead containing surface cover.

Post electrochemical studies by LEED and AES of the superficial atomic structure of a Au (110) electrode

By combining electrochemistry with electronic methods of surface analysis it is possible to obtain valuable information about the metal-electrolyte interface. This implies a transfer of the electrode from the UHV to the electrochemical cell and vice versa without extensive loss of the surface quality. A glove box system has been developed with an ultra purification system for the atmosphere (O 2 < 1 μg g −1) and used in the case of Au (110). No irreversible electrochemically induced surface modification of the Au (110) surface has been found in post electrochemical LEED patterns.

Predominant obligate anaerobes in human carious dentin.

With the adoption of an anaerobic glove box system, we isolated and identified the predominant micro-organisms in lesions of carious dentin from four permanent third molars. The overwhelming majority of the micro-organisms isolated from both shallow and deep layers of carious dentin were obligate anaerobes, suggesting that conditions in the dentin were strictly anaerobic. The predominant obligate anaerobes were Gram-positive rods which were identified as members of the following genera: Propionibacterium, Eubacterium, Arachnia, Lactobacillus, Bifidobacterium, and Actinomyces. Clostridia, Gram-negative rods (Bacteroides and Fusobacterium) and Gram-positive cocci (Peptococcus, Peptostreptococcus, and Streptococcus) were also isolated, although they constituted a minor part of the flora.

Species identificafion of Lactobacillus, Bifidobacterium and Actinomyces isolated from human carious dentine.

Fifty-eight obligately anaerobic rods, which were isolated from human carious dentine and produced lactic acid as a major end product, namely Lactobacillus, Bifidobacterium and Actinomyces, were identified. Of 26 isolates ofLactobacillus, 9 isolates were identified as L. minutus, 8 isolates as L. plantarum, 3 isolates as L. crispatus and 3 isolates as L. catenaforme (including1 L. catenaforme-like strain). One isolate resembled L. cellobiosus and one resembled L. brevis. The other one could not be identified. Of 19 isolates of Bifidobacterium, 8 isolates were identified as B. bifidum (including 3 B. bifidum-like strains) and 11 isolates resembled B. breve. Of 13 isolates of Actinomyces, 7, 5 and 1 isolates were identified A. israelii, A. naeslundii and A. Odontolyticus, respectively. The species identifications of these isolates provide informations that the obligately anaerobic species of genus Lactobacillus and the obligately anaerobic strains of Actinomyces species were isolated frequently from carious dentine with adoption of an anaerobic glove box system.

Oxidation of tritium gas in glovebox atmosphere using CuO column.

A multiple barrier containment concept for tritium control is proposed to provide minimal release to the environment. The rationale for this design is the prevention of the dilution of tritium within each barrier so that the tritium can be recovered before it penetrates to the outer barrier. Oxidation performances of CuO sponge column in the inert atmosphere of glovebox system are discussed and following results are obtained. The oxidation column efficiency or KFaVcat/Q plays an important role in the tritium level decrease on the glovebox atmosphere. The recommended value of the column efficiency is 20–100. The isotope effect in chemical oxidation of H2, D2 and HT is 1, 1/6 and 1/12, respectively. Use of CuO sponge for the atmosphere in the presence of oxygen is not recommended because of the retardation of chemical oxidation rate.

Experimental Verification of Tritium Control by Glove-Box Containment

Concepts being developed for tritium containment at proposed fusion power plants will rely on existing laboratory experiences. The successful operation of a glove-box containment system was demonst...

A glove box system for the manipulation of air sensitive compounds

The authors examined several glove boxes and recirculating systems and have arrived at what they believe to be an excellent glove box system for handling air sensitive compounds.

Comparison of three anaerobic systems for the isolation of anaerobic bacteria from clinical specimens.

An anaerobic glove box, the GASPAK jar system, and a roll-streak tube system with prereduced, anaerobically sterilized medium were compared for recovery of anaerobic bacteria from selected clinical specimens collected in anaerobic tubes. Both prereduced plating media held in an anaerobic glove box for a minimum of 48 hr. before use and fresh plating media exposed to atmospheric oxygen for no longer than 1 hr. were used in the glove box and GASPAK systems. In general, the recoveries of anaerobic bacteria with the three systems were comparable. Bacteroides melaninogenicus strains were recovered with the glove box and GASPAK systems and were not detected with roll-streak tubes, but the PRAS medium used in the roll-streak tube system did not contain hemin or menadione, whereas some of the media used in the other systems did. Only one organism, a peptostreptococcus, was recovered in the roll-streak tube system and not in the GASPAK or glove box systems. Of 29 anaerobes isolated from the 15 specimens examined, 28 were recovered in both the GASPAK and glove box systems and 23 were isolated with the roll-streak tube system. The advantages and disadvantages of each system are discussed.