Gas Cartridges Research Articles

Versatile PU seal accommodates different dimensions of valves on gas cartridges

Freudenberg Sealing Technologies has developed a versatile seal for a water treatment device that not only filters tap water, but also enriches it with minerals and, if desired, carbonic acid. As this brief focus article explains the seal, made from polyurethane (PU), is capable of accommodating the different dimensions of valves used on carbon dioxide cartridges, ensuring that flow-control components are joined with a secure seal.

A monolithic composite based on zeolite-like metal-organic framework@divinylbenzene polymer separates azeotropic fluorocarbon mixture efficiently

Organic monolithic columns are mainly used to separate macromolecules; however, many attempts to extend their performance toward small molecules were examined by incorporating micro- and nanoparticles. The incorporation technique enabled utilizing organic monoliths in gas chromatography (GC) for small molecules, which are still scarce. Here, we prepared a composite matrix of capillary monolithic columns of a zeolite-like metal-organic framework with a sodalite topology (sod-ZMOF) and Divinylbenzene polymer (DVB) for GC separations under 0.5 MPa. Relatively short DVB monolithic columns (18 cm long × 0.25 mm i.d.) incorporated with a tiny amount of sod-ZMOF nanoparticles (0.7 and 1.17 wt%) with an average particle size of 225 nm were successfully fabricated and used to separate linear alkanes and polar probes mixtures with increasing resolution up to 3.7 and 5.1 times, respectively, compared to a blank DVB monolithic column. A high-performance separation of linear alkanes series mixture (methane to decane) was exhibited in less than 2 min. McReynolds constants revealed that sod-ZMOF provided the composite monolith with a nonpolar character yielding a negative average polarity value smaller than the standard squalene column. An Excellent retention time of pentane and octane day-to-day reproducibility was achieved during 16 days and over more than 500 runs with RSD% of 2.25% and 3.3% using a composite monolithic column with 5 mg mL−1 sod-ZMOF (5-ZMOF@DVB). In addition, a qualitative determination of the gas mixture content of three commercially available Lighter gas cartridges was performed via the 5-ZMOF@DVB column. Finally, successfully separating an azeotropic freon mixture of difluoromethane (R-32) and pentafluoroethane (R-125) was achieved with a selectivity of up to 4.84. A further thermodynamic study related the preferential adsorption of R-125 to entropic factors rather than enthalpic while trapping inside ZMOF pores. This work sheds light on utilizing the infinite diversity of MOFs and combining their properties with high permeability and easily fabricated organic monoliths for GC separations of light molecules and gasses. Furthermore, the study highlights the role of GC as an easy and fast approach for the preliminary evaluation of the separation efficiency of porous polymers.

Organic minerals restore the acid-base and electrolyte balance in broiler chicks with nutritionally induced metabolic acidosis

The present study evaluated the blood gas and electrolyte balance in broiler chicks fed with diets containing different levels of vitamin premix (VM) and forms of trace minerals. VM was included at 30 or 100% of commercial levels. Trace minerals were provided as either inorganic (IOM) or organic trace minerals (OTM). This experiment, which used one-day-old male broiler chicks, featured a factorial treatment structure with four treatments using 12 replicate pens (22 chicks/pen), each arranged in a randomised complete block design. An i-STAT® handheld, point-of-care, clinical analyser, loaded with blood gas, lactate and electrolyte cartridges, was used to analyse blood samples. Significant interactions for vitamin levels and mineral form were observed for bicarbonate, base excess, total carbon dioxide, ionised calcium and haematocrit levels. Using OTM, but not IOM, in the premix resulted in blood gas and electrolyte values that were comparable to those in 100% VM-fed group. The consumption of 30% VM reduced pO2 (P<0.01), sO2 (P<0.01), pH (P=0.05) and K+ with concomitant increases in lactate, glucose and Na+ (P<0.03). However, OTM tended to reverse the Na+ effect (P=0.05) along with higher partial CO2 (P<0.05). These results demonstrated the negative effects of a 30% VM diet on blood gas and electrolyte balance, which triggered nutritionally induced metabolic acidosis. However, metabolic acidosis induced by underfeeding VM (30%) was restored or normalised by using OTM, but not IOM, in the vitamin-mineral premix.

Microfabricated ionic liquid column for separations in dry air

Micro gas chromatography (µGC) is a technique developed for rapid, in situ analysis of volatile organic compounds (VOCs) for environmental protection, industrial monitoring, and toxicology. While reduced µGC size and power requirements allow for increased portability, the low moisture and oxygen resilience of current microcolumn technology result in increased peak broadening and tailing for humid samples, which necessitates the use of bulky helium or nitrogen carrier gas cartridges. Developing a microcolumn to address these deficiencies is desirable to improve µGC field performance and further reduce µGC system size. This paper reports the development and characterization of a microfabricated phosphonium ionic liquid (µIL) column and demonstrates separation of both polar and nonpolar compounds using this column via analyses of alcohols, chloroalkanes, aromatics, aldehydes, fatty acid methyl esters, and alkanes. The µIL column achieved operation at temperatures up to 345 °C for fatty acid methyl ester and alkane separation. Notably, all separations in this study used dry air as the carrier gas, showing that analysis of a diverse range of compounds was possible in the presence of oxygen. After exposure to dry air for 48 h at temperatures up to 220 °C, the µIL column's peak capacity was only degraded by 8.92%, which validated its long-term robustness against oxygen. The column's separation performance was not degraded by high moisture concentrations or long-term moisture exposure, also manifesting its robustness to moisture. The high temperature, moisture, and oxygen resilience of the µIL column enable more rapid separations in varying field environments without requiring additional µGC accessories (e.g., humidity filters and carrier gas cartridges). The µIL column is therefore expected to be useful for integration into future µGC devices.

Is pressurized exhaust an effective tool against burrowing rodents?

ABSTRACTBurrow fumigants are lethal tools for mitigating rodent damage, but until recently, only gas cartridges and aluminum phosphide were registered for use in California, USA. In 2012, pressurized exhaust machines that emit carbon monoxide were legalized for use, although their efficacy was unknown. From 2014 through 2015, we assessed the efficacy of the Pressurized Exhaust Rodent Controller (PERC) for managing California ground squirrels (Otospermophilus spp.) and pocket gophers (Thomomys bottae) across various localities in California. The PERC machine proved effective for California ground squirrels (efficacy = 83%), although results were variable across the 2 study areas (efficacy = 66–100%), potentially due to differences in soil moisture or injection time across study sites. The PERC machine was moderately effective at controlling pocket gophers (efficacy = 68%), but performed better than in previous studies. Pressurized exhaust machines show promise as a tool for managing burrowing rodents. © 2017 The Wildlife Society.

The Use of Forced Gas Rodent Burrow Fumigation Systems and the Potential Risk to Humans

Author(s): Eisemann, John D.; Moulton, Rachael S.; Witmer, Gary W. | Abstract: The use of fumigants has been commonly practiced for decades to manage burrowing rodent populations in both agricultural and urban habitats. Stories abound about farmers and ranchers illegally fumigating rodent burrows by inserting toxic gas-producing road flares into burrow openings or by simply piping automotive exhaust into burrows systems. Legal fumigant technology includes incendiary devices such as gas cartridges that produce carbon monoxide, and highly reactive magnesium and aluminum phosphide pellets that produce toxic gasses by reaction with the atmosphere. These devices rely on passive diffusion of the toxic gasses through the burrow system. Recently, products have been introduced to the market that force toxic gasses into burrow systems by using blowers or pressurized gas systems. The effectiveness of fumigation systems where toxic gasses, such as carbon monoxide, are allowed to passively infiltrate burrow systems are limited in their geographical range, and as a result are limited in the potential risk to humans or other organisms. Regardless, these products have traditionally had use restrictions based on the proximity to structures and other inhabited areas. The use of systems where toxic gasses are forcefully blown into burrow systems present a greater hazard potential. This manuscript examines the potential risk, in terms of US EPA Standards, for carbon monoxide exposure; published data on carbon monoxide levels in burrow systems; burrow morphology of various burrowing species; and suggests safe distance standards for burrow fumigation activities conducted around structures and other human-occupied habitats.

Quantitative determination of n-butane metabolites in three cases of butane sniffing death

Butane is an addictive volatile substance like toluene. We report three forensic autopsy cases of sudden death that occurred while sniffing n-butane and isobutane from portable gas cartridges. n-Butane and isobutane were detected in all three cases. In cases 1–3, n-butane concentrations in heart blood were 54.3, 25.5, and 30.7μg/mL, respectively. These concentrations were considered fatal according to the previous reports. In addition, n-butane metabolites (2-butanol and 2-butanone) were detected in cases 1 and 3 but not in case 2. Blood levels of 2-butanol and 2-butanone were 6.5 and 1.8μg/mL, respectively, in case 1, and 6.3 and 5.6μg/mL, respectively, in case 3. According to the police investigation, the decedent in case 1 had misused butane gas for more than 6 months in the period leading up to death. The decedent in case 3 also had a history of chronic misuse of butane gas. There was no history of chronic misuse of butane gas by the decedent in case 2. It was suspected that he attempted suicide via inhalation of butane gas using a plastic bag, leading to a rapid death. The presence or absence of n-butane metabolites might reflect the way of butane inhalation, such as the frequency and duration. Although additional experimental and case studies are necessary to establish the forensic applications of n-butane metabolite detection, it may be a useful method to understand the decedents’ pattern of butane sniffing before death.

Fatal butane inhalation from gas cartridges: a case report and literature review

Volatile substances are commonly misused with easy-to-obtain commercial products, such as glue, shoe polish, nail polish remover, butane lighter fluid, gasoline and computer duster spray. This report describes a case of sudden death of a 29-year-old woman after presumably inhaling gas cartridge butane from a plastic bag. Autopsy, pathological and toxicological analyses were performed in order to determine the cause of death. Pulmonary edema was observed pathologically, and the toxicological study revealed 2.1μL/mL of butane from the blood. The causes of death from inhalation of volatile substances have been explained by four mechanisms; cardiac arrhythmia, anoxia, respiratory depression, and vagal inhibition. In this case, the cause of death was determined to be asphyxia from anoxia. Additionally, we have gathered fatal butane inhalation cases with quantitative analyses of butane concentrations, and reviewed other reports describing volatile substance abuse worldwide.

Funicular myelosis in a butcher: it was the cream cans.

Background. Funicular myelosis is a known consequence of exposure to nitrous oxide. Nevertheless, there are only a few clinical trials assessing its long-term effects and there is no literature about the role of nutritional vitamin B12 supplementation in the context of nitrous oxide abuse. Case Descriptions. We diagnosed funicular myelosis in a young butcher, who consumed high amounts of meat regularly. Since the diagnostic process did not reveal any metabolic causes, reinterrogation of the patient uncovered recreational abuse of nitrous oxide out of whipped cream can gas cartridges. After stopping abuse and supplementation of vitamin B12, the patient recovered almost completely. Conclusions. In our case, even high nutritional vitamin B12 uptake could not compensate the noxious effects of nitrous oxide. Since there are emerging reports of increasing misuse, this should be considered in the diagnostic and therapeutic care of patients with nitrous oxide abuse. Furthermore, our case emphasizes that patients with vitamin B12 deficiency should be assessed for nitrous oxide abuse.

エアゾール缶等の分別排出における住民の意識と行動に関する分析

一般家庭から排出されるごみには，エアゾール缶やコンロ用カセットボンベなど，爆発性や引火性のある品目が含まれているため，収集時や処理時に全国で毎年多くの火災事故が発生しており，効果的な事故防止対策が求められている。本研究では，住民を対象とした質問紙調査を行い，2段階モデルに基づき住民のエアゾール缶等に関する分別行動と，それを規定する要因との解析を行った。住民の協力を得るためには，必要な情報を周知徹底すること，年齢別のPR啓発が必要であること，情報提供はうっかり対策にも効果的であることなどを明らかにした。環境問題への意識と行動に加え，安全行動面にも配慮してモデルを構築し，行動分析を行っており，エアゾール缶等による火災事故を防止し安全な収集作業を確立するための有効な知見が得られたと考えられる。

The Applicability of Burrow Fumigants for Controlling Belding’s Ground Squirrels in Alfalfa

Rodenticides are often used to control burrowing rodents but have not been overly efficacious for Belding’s ground squirrels due to poor bait acceptance. This has left alfalfa growers searching for alternative options for controlling this rodent species. As such, we tested aluminum phosphide and gas cartridge burrow fumigation in an alfalfa field in Butte Valley, CA, to determine if either of these approaches were efficacious and cost effective for controlling Belding’s ground squirrels. A comparison of the number of burrows treated and the number of burrows reopened 48-hours post-treatment indicated that both burrow fumigants were highly effective (aluminum phosphide = 94-98%, gas cartridges = 100%). The average cost per application was $1.05 and $2.92 for aluminum phosphide and gas cartridges, respectively. Given the almost 3-fold difference in cost of application between the two approaches, aluminum phosphide appears to be the more practical approach for Belding’s ground squirrel control. Although we currently lack an approach for estimating the amount of damage that Belding’s ground squirrels are likely to cause to an alfalfa field, it seems plausible that burrow fumigation could be a cost effective approach to reduce damage caused by this species, particularly if long-term control can be obtained. Possible long-term management options for Belding’s ground squirrels are discussed.

Outcome of Craniocerebral Gunshot Injuries in the Civilian Population. Prognostic Factors and Treatment Options

Gunshot wounds to the head are rare in Europe. They may be inflicted by low-velocity handguns, captive bolt guns and tear gas cartridges and mostly result from suicide attempts. The experience of neurosurgeons with this kind of traumatic injury is decreasing; the aim of this study was therefore to analyse prognostic factors which help to decide whether or not to operate and to discuss treatment options. Thirty patients with gunshot head injuries treated in our hospital from 1993 to 2008 were retrospectively evaluated. Glasgow Coma Scale (GCS) score, pupil reactivity, lesion localisation, number of bone fragments, intracranial pressure (ICP), midline shift, hypotension, and dural penetration were analysed for their prognostic value. Surgically and non-surgically treated patients were evaluated separately. Complications were registered. A low GCS of 3-8, fixed pupils, >2 bone fragments, bilobar or posterior fossa/brainstem lesions and ICP >45 mmHg were indicators of a poor prognosis. Patients with a GCS of 3-8 and two non-reactive pupils should not be operated. If one or both of the pupils are reactive, surgery should be performed irrespective of the GCS score, except in patients with translobar/transventricular wounds. Even if there are no clear contraindications to surgery, the outcome is expected to be poor in patients with a low GCS score, midline shift >10 mm, >2 bone fragments in the brain, and a bilobar, posterior fossa/brainstem or ventricular lesion and ICP >45 mmHg. When surgery is performed the wound and the missile or bone track should be debrided meticulously, the wound and dura should be closed in a watertight fashion and antibiotic prophylaxis as well as tetanus serum should be given.

Fumigation of California Ground Squirrels Revisited: Are Fumigants an Effective Method for Controlling Ground Squirrels?

Fumigation with either gas cartridges or aluminum phosphide is often considered to be an effective method for controlling California ground squirrel populations, although few studies have corroborated their effectiveness. Additionally, utilizing aluminum phosphide in combination with gas cartridges could increase effectiveness of both fumigants by indicating additional burrow openings through escaping smoke from gas cartridges and allowing for treatment of these additional openings with aluminum phosphide, which is a cheaper and potentially more effective material. Therefore, we compared the efficacy of gas cartridges, aluminum phosphide, and a combined treatment on ground squirrel populations from mid-April through early May 2009 to determine which was most effective. We established 4 plots (3 treatments plus control) at each of 2 treatment sites in Madera County, California. All plots were between 1 and 2 ha in size with survey areas of 0.3 - 0.5 ha centrally located within the plot. Ground squirrels were visually counted within survey areas for 3 consecutive days prior to treatment. Following counting, treatments were applied. Forty-eight hours post-treatment, squirrels were again counted within survey areas to determine percent control. These counts were repeated the following 2 days. All treatments were then reapplied for the same plots, with similar surveys again following 48 hours post-treatment. We found that all fumigation methods resulted in marginal to exceptional control of ground squirrels (percent control: gas cartridges = 62 - 86%, aluminum phosphide = 97 - 100%, gas cartridges + aluminum phosphide = 59 - 71%). We suggest aluminum phosphide use could be expanded to increase ground squirrel control in California, given its high efficacy combined with its relatively cheap material cost.

Thermal Stress and Point-of-Care Testing Performance: Suitability of Glucose Test Strips and Blood Gas Cartridges for Disaster Response

Point-of-care testing (POCT) devices are deployed in the field for emergency on-site testing under a wide range of environmental conditions. Our objective was to evaluate the performance of glucose meter test strips and handheld blood gas analyzer cartridges following thermal stresses that simulate field conditions. We evaluated electrochemical and spectrophotometric glucose meter systems and a handheld blood gas analyzer. Glucose test strips were cold-stressed (-21 degrees C) and heat-stressed (40 degrees C) for up to 4 weeks. Blood gas cartridges were stressed at -21 degrees C, 2 degrees C, and 40 degrees C for up to 72 hours. Test strip and cartridge performance was evaluated using aqueous quality control solutions. Results were compared with those obtained with unstressed POCT strips and cartridges. Heated glucose test strips and blood gas cartridges yielded elevated results. Frozen test strips and cooled cartridges yielded depressed glucose and blood gas results, respectively. Frozen cartridges failed. The performance of glucose test strips and blood gas cartridges was affected adversely by thermal stresses. Heating generated elevated results, and cooling depressed results. Disaster medical assistance teams and emergency medical responders should be aware of these risks. Field POCT devices must be robust to withstand adverse conditions. We recommend that industry produce POCT devices and reagents suitable for disaster medical assistance teams.

Fatal cranial shot by blank cartridge gun: Two suicide cases

Blank firing pistols are generally considered to be harmless and these guns are not accepted as being firearms in most countries. Due to lack of legal regulations these guns are easily purchased by anyone aged over 18 years. Reports of serious injuries and even fatalities due to these guns are increasing in the literature. These guns when modified or even unmodified can cause serious and potentially fatal injuries. Without doing any changes to the barrel, using blank or tear gas cartridges, firing at contact range can cause penetration of gas into the body including bone originated from gunpowder. We report two suicide cases shooting themselves at temporal region with a blank cartridge gun at contact range. There was no foreign body on radiological examination and there was no trajectory of a bullet inside the brain. In both cases the wound was at the right temporal region and there was defect at temporal bone. There was circular soot around this bone defect. The injury of the brain tissue was localized at the level of the defect but there was widespread subarachnoidal bleeding. We discussed the potential danger of these guns and stressed the need of legal regulations concerning these guns.

압력 방출밸브를 장착한 이동식 부탄연소기용 부탄캔의 분출가스 확산 실험 및 해석

In the last five years, 91 accidents from portable gas ranges and non-refillable metallic gas cartridges have occurred. The gas cylinder instllaed with a relief valve was developed to prevent an explosive accident from the gas cartridge. In this study it was carried out to evaluate the safety of a gas cylinder mounted with a relief valve which can prevent an explosion. Under the real using condition and the extreme condition the gas cylinder is heated with an electric heater. Simultaneously, the operating pressure is checked and the suitability of releasing flux is evaluated. And the possibility of fire or explosion was tested when the gas was released from the relief valve at the real using condition. Using a numerical simulation method, the diffusion of butane gas released from a relief valve was visualized.

Analysis of pesticide gas cartridges.

Charcoal and sodium nitrate, the active ingredients in pesticide gas cartridges, are quantified via carbon analysis and ion chromatography, respectively. Linearity was excellent (R(2) > 0.995) over a range consisting of 50-150% of the target concentration for both ingredients. The coefficient of variation for the replicate analyses of gas cartridges over multiple days was <4% for both analytes. Using the results from the analysis of two batches of gas cartridges, theoretical populations were modeled and used to determine practical sampling strategies to support a quality control program for a gas cartridge manufacturing operation. This modeling indicates that the analysis of three cartridges from each of five different lots would produce mean values for both active ingredients that are within 5% of the true mean >99% of the time.

Cost-effectiveness of five burrow fumigants for managing black-tailed prairie dogs

We evaluated the cost-effectiveness of two solid form burrow fumigants (aluminum phosphide and gas cartridges) and three pressurized gas–liquid burrow fumigants (methyl bromide, chloropicrin, and a methyl bromide–chloropicrin mixture) for managing black-tailed prairie dogs ( Cynomys ludovicianus). Fifty-two variable-sized plots, including 25 treatment and 25 control burrows, were established within 13 prairie dog colonies in central Nebraska during spring 1989. Each group of 25 treatment burrows was fumigated with one of the five fumigants according to label directions or manufacturer recommendations. All five fumigants reduced burrow activity 95–98%, as measured by a plugged burrow technique. No significant differences in efficacy ( P=0.453) were detected among the five treatments. Total costs for materials and labor for the aluminum phosphide and gas cartridges, excluding application equipment, were twice ($75.00 to $96.88 ha −1) the cost of the pressurized gas–liquid fumigants ($37.67 to $41.76 ha −1). Costs for the application equipment were considerably higher for the pressurized materials. Each treatment required labor for burrow plugging, which accounted for 50–75% of the total cost. None of the products tested met all requirements of a proposed selection criteria for fumigants.

Fumigant dispersal in pocket gopher burrows and benefits of a blower system

Author(s): Nolte, Dale L.; Wagner, Kimberly K.; Trent, Andrew; Bulkin, Stephen | Abstract: Efforts to establish tree seedlings on sites infested with high populations of pocket gophers (Thomomys spp.) can be futile unless population control measures are implemented. Fumigants are a possible means to reduce pocket gopher populations although the efficacy of fumigants on reforestation sites has been minimal. We conducted a series of experiments to monitor the movement of carbon monoxide through burrow systems and to assess the potential benefits of a blower system. In the first experiment, carbon monoxide was introduced to an artificial burrow system by burning either one or two gas cartridges concurrently or consecutively. The blower was tried at different speeds for varied durations. Carbon monoxide concentration was monitored with sensors that had a detection range from 0 to 5,000 parts per million. Burning the cartridges without the blower was not effective in distributing carbon monoxide. The most effective fumigant dispersal occurred when the blower was used at a low speed for only the period while a cartridge was burning. Burning two cartridges simultaneously was the most effective burn configuration. Results from a second experiment, using vacated pocket gopher burrows instead of an artificial system, were similar to those recorded for the first experiment. Subsequently, we conducted field trials using a blower to disperse carbon monoxide to reduce pocket gopher populations on reforestation sites. These trials did not demonstrate a reduction in pocket gopher activity. We speculate this was because existing burrow plugs prevented the gas from dispersing through the systems or because pocket gophers rapidly blocked burrows when they detected the gas, thus preventing exposure to lethal gas concentrations.

Fatal neck injuries caused by blank cartridges

We report three cases where fatal neck injuries were caused by blanks from starting pistols. The weapons were loaded with blank cartridges or tear gas cartridges. Neither live ammunition nor any form of projectile was used. All three cases involved a contact discharge. The gas pressure caused by firing the weapons created extensive wound cavities in all three cases. Each victim died from blood loss as a result of ruptured cervical vessels; there were no air embolisms. In one case, a man shot himself eight times with two different starting pistols, and the wounds could be matched to each gun by the muzzle imprint marks on the neck.