160 research outputs found

    Evaluating Contaminants of Emerging Concern in Commercial Biosolid-based Fertilizers

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    The production and popularity of commercially available biosolid-based fertilizers are increasing because of their economic, environmental, and plant nutrition benefits, particularly in urban and suburban areas. Because biosolid-based fertilizers are derived from waste water treatment plant residuals, we hypothesized that there is the potential for micropollutants to persist in these products. Their presence would be of particular concern due to their potential impact on human and ecological health and risk of bioaccumulation. This study involves quantifying contaminants of emerging concern in three biosolid-based fertilizers, and 2 non-biosolid-based fertilizers, a composted animal manure and an organic compost. Our extraction method employed ultrasonic assisted solid-liquid extraction followed by a 20 h equilibration during which samples were rotated end-over-end. Prior to analysis, all solvent extracts were concentrated under nitrogen and cleaned up with ENVI-carb to minimize matrix effects during sample analysis. High performance liquid chromatography tandem mass spectrometry (LC-MSMS) and quadrupole time of flight liquid chromatography mass spectrometry (QTOF-LCMS) were used to identify and quantify a suite of micropollutants including perfluoroalkyl substances (PFASs), hormones, parabens, pharmaceuticals, and personal care products. Variable levels of contaminants ranging from 8.22 to 11,300 ppb were found in the biosolid fertilizers, while the nonbiosolid fertilizers contained much smaller concentrations. Milorganite had 14 contaminants, OceanGRO had 13, Elite Lawn had 16, New Plant Life Composted Manure had 1, and Pro-Mix Ultimate Organic Mix had 3. Although many of these chemicals persist in commercially available biosolid-based fertilizers, future research is still needed to determine what, if any, potential risk these contaminants may pose to human or ecological health at the concentrations detected

    Noise Thermometry with Two Weakly Coupled Bose-Einstein Condensates

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    Here we report on the experimental investigation of thermally induced fluctuations of the relative phase between two Bose-Einstein condensates which are coupled via tunneling. The experimental control over the coupling strength and the temperature of the thermal background allows for the quantitative analysis of the phase fluctuations. Furthermore, we demonstrate the application of these measurements for thermometry in a regime where standard methods fail. With this we confirm that the heat capacity of an ideal Bose gas deviates from that of a classical gas as predicted by the third law of thermodynamics.Comment: 4 pages, 4 figure

    Realization of a single Josephson junction for Bose-Einstein condensates

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    We report on the realization of a double-well potential for Rubidium-87 Bose-Einstein condensates. The experimental setup allows the investigation of two different dynamical phenomena known for this system - Josephson oscillations and self-trapping. We give a detailed discussion of the experimental setup and the methods used for calibrating the relevant parameters. We compare our experimental findings with the predictions of an extended two-mode model and find quantitative agreement

    ПЕРСПЕКТИВИ СТВОРЕННЯ ЕФЕКТИВНО ФУНКЦІОНУЮЧОГО ФІНАНСОВОГО МЕХАНІЗМУ ІННОВАЦІЙНОГО РОЗВИТКУ ПІДПРИЄМСТВ В УКРАЇНІ

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    Висвітлюються проблеми і перспективи створення ефективно функціонуючого фінансового механізму інноваційного розвитку підприємств в Україні. Розроблено модель, яка забезпечує формування стратегії інноваційного розвитку підприємства.Problems and prospects of effectively functioning financial mechanism's creation of innovative enterprise development in Ukraine are lighted. A model is developed, which provides forming of the innovative strategy enterprises' development

    A Single Laser System for Ground-State Cooling of 25-Mg+

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    We present a single solid-state laser system to cool, coherently manipulate and detect 25^{25}Mg+^+ ions. Coherent manipulation is accomplished by coupling two hyperfine ground state levels using a pair of far-detuned Raman laser beams. Resonant light for Doppler cooling and detection is derived from the same laser source by means of an electro-optic modulator, generating a sideband which is resonant with the atomic transition. We demonstrate ground-state cooling of one of the vibrational modes of the ion in the trap using resolved-sideband cooling. The cooling performance is studied and discussed by observing the temporal evolution of Raman-stimulated sideband transitions. The setup is a major simplification over existing state-of-the-art systems, typically involving up to three separate laser sources

    Molecules cooled below the Doppler limit

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    The ability to cool atoms below the Doppler limit -- the minimum temperature reachable by Doppler cooling -- has been essential to most experiments with quantum degenerate gases, optical lattices and atomic fountains, among many other applications. A broad set of new applications await ultracold molecules, and the extension of laser cooling to molecules has begun. A molecular magneto-optical trap has been demonstrated, where molecules approached the Doppler limit. However, the sub-Doppler temperatures required for most applications have not yet been reached. Here we cool molecules to 50 uK, well below the Doppler limit, using a three-dimensional optical molasses. These ultracold molecules could be loaded into optical tweezers to trap arbitrary arrays for quantum simulation, launched into a molecular fountain for testing fundamental physics, and used to study ultracold collisions and ultracold chemistry

    Incidence of epidural haematoma and neurological injury in cardiovascular patients with epidural analgesia/anaesthesia: systematic review and meta-analysis

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    BACKGROUND: Epidural anaesthesia is used extensively for cardiothoracic and vascular surgery in some centres, but not in others, with argument over the safety of the technique in patients who are usually extensively anticoagulated before, during, and after surgery. The principle concern is bleeding in the epidural space, leading to transient or persistent neurological problems. METHODS: We performed an extensive systematic review to find published cohorts of use of epidural catheters during vascular, cardiac, and thoracic surgery, using electronic searching, hand searching, and reference lists of retrieved articles. RESULTS: Twelve studies included 14,105 patients, of whom 5,026 (36%) had vascular surgery, 4,971 (35%) cardiac surgery, and 4,108 (29%) thoracic surgery. There were no cases of epidural haematoma, giving maximum risks following epidural anaesthesia in cardiac, thoracic, and vascular surgery of 1 in 1,700, 1 in 1,400 and 1 in 1,700 respectively. In all these surgery types combined the maximum expected rate would be 1 in 4,700. In all these patients combined there were eight cases of transient neurological injury, a rate of 1 in 1,700 (95% confidence interval 1 in 3,300 to 1 in 850). There were no cases of persistent neurological injury (maximum expected rate 1 in 4,600). CONCLUSION: These estimates for cardiothoracic epidural anaesthesia should be the worst case. Limitations are inadequate denominators for different types of surgery in anticoagulated cardiothoracic or vascular patients more at risk of bleeding
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