Deuterium Content Research Articles

Retention of deuterium in beryllium: A combined investigation using TDS, ERDA and EBS

We have studied the retention of deuterium in beryllium, implanted with an energy of 500 eV/D, using a combination of thermal desorption spectroscopy, elastic recoil detection analysis and elastic backscattering spectroscopy. The parallel use of these techniques allowed us to directly quantify the absolute deuterium content reduction of the sample for specific desorption peaks observed during thermal annealing. In addition, the presence of a beryllium oxide surface layer was observed, despite sputter-cleaning of the sample was initially conducted in-situ . A main result was that ∼ 85 % of the retained deuterium got released during the primary desorption peak at 400 K. A smaller, secondary desorption peak was identified at 540 K. All deuterium could be removed from the Be sample by heating it to a temperature of 800 K. • Deuterium retention in saturated beryllium studied for 500 eV/D irradiation. • Parallel temperature desorption spectroscopy and ion beam analysis achieved in-situ. • 85% of deuterium is released at primary desorption peak at 400 K. • BeO formation during implantation was observed in UHV conditions.

Hydrogen-induced volume changes, dipole tensor, and elastic hydrogen-hydrogen interaction in a metallic glass

Hydrogen and its isotopes, absorbed in metals, induce local stress on the atomic structure, which generates a global expansion in proportion to the concentration of hydrogen. The dipole force tensor and its interaction with the stress fields give rise to an effective attractive nonlocal potential between hydrogen atoms---the elastic hydrogen-hydrogen interaction---which is a key quantity governing the phase transitions of hydrogen in metals. While the dipole tensor and the elastic interaction have been researched in crystalline materials, they remain experimentally unexplored in metallic glasses and it is unclear how these quantities are affected by the lack of point group symmetries. Here, we investigate both experimentally and theoretically the volume changes, the components of the force dipole tensor, and ultimately the elastic hydrogen-hydrogen interaction in the metallic glass ${\mathrm{V}}_{80}{\mathrm{Zr}}_{20}$. In situ neutron reflectometry was used to determine the deuterium-induced volume changes as a function of deuterium concentration. The one-dimensional volume expansion is found to change by more than 14% without any structural degradation, up to concentrations of one deuterium atom per metal atom. From the expansion, we determine that the out-of-plane component of the elastic dipole tensor is remarkably similar to a composition weighted sum of the ones found in crystalline vanadium and zirconium. Via ab initio calculations of both free and biaxially constrained expanded metallic structures, we determine that the trace of the dipole tensor varies with hydrogen concentration and is essentially invariant of global elastic boundary conditions. As a consequence, the elastic hydrogen-hydrogen interaction energy is found to be concentration-dependent as well, illustrating that the disordered nature of a metallic glass does not impede the mediation of the elastic attraction, but rather allows it to vary with hydrogen content.

Effects of self-irradiation on deuterium retention and reflectivity of molybdenum, fusion plasma-facing material: Combined experimental and modeling study

Molybdenum is used as plasma-facing material in tokamaks and as material for plasma optical diagnostics mirrors. Harsh conditions of neutron irradiation, exposure to hydrogen isotopes and helium ions, and high operating temperatures result in degradation of the molybdenum surface and ultimately limit their lifetime in a fusion power plant. In the current paper, intake and subsequent thermal release of deuterium from self-irradiated by high energy (1 MeV) ions molybdenum as a function of irradiation dose are investigated. Several characteristic temperature regions where deuterium release takes place are identified and attributed to trapping of deuterium in intrinsic and radiation-induced microstructure defects. This attribution is further validated by molecular dynamics modeling, which confirms that increase and saturation of vacancy concentration found in simulations follows increase and saturation of experimentally determined deuterium content. Deuterium inventory and vacancy content saturate at a damage level of around 0.2 dpa (displacement per atom), similar to recent modeling and experimental studies of iron and tungsten. Reflectivity measurements of irradiated molybdenum show that it is only slightly affected by damage up to 1 dpa.

Adsorption of Methylene Blue on the Surface of Polymer Membrane; Dependence on the Isotopic Composition of Liquid Matrix.

As was found in our previous works, when Nafion swells in water, polymer fibers unwind into the bulk of the surrounding liquid. This effect is controlled by the content of deuterium in water. Here, we present the results of studying the dynamics of methylene blue (MB) adsorption on the Nafion surface for MB solutions based on natural water (deuterium content is 157 ppm, the unwinding effect occurs) and based on deuterium-depleted water (DDW; deuterium content is 3 ppm, there is no unwinding). In addition, we studied the dynamics of water desorption during drying of the Nafion polymer membrane after soaking in MB solution based on natural water and DDW. It turned out that in the case of natural water, the rate of MB adsorption and water desorption is higher than in the case of DDW. It also turned out that the amount of MB adsorbed on the membrane in the case of natural water is greater than in the case of DDW. Finally, it was found that the desorption of water during drying is accompanied by a rearrangement of the absorption spectrum of Nafion. This rearrangement occurs earlier in the case of DDW. Thus, by infinitesimal changes in the deuterium content (from 3 to 157 ppm) in an aqueous solution, in which a polymer membrane swells, we can control the dynamics of adsorption and desorption processes. A qualitative model, which connects the observed effects with the slowing down of diffusion processes inside the layer of unwound fibers, is proposed.

Photoredox-Catalyzed C–H Trideuteromethylation of Quinoxalin-2(1H)-ones with CDCl3 as the “CD3” source

Herein, readily available and inexpensive CDCl3 was first identified as a new trideuteromethylation reagent under photoredox-catalyzed conditions. Thus, a facile photocatalytic protocol for the C-H trideuteromethylation of quinoxalin-2(1H)-one was achieved. This operationally straightforward transformation displays a broad scope and provides a new route to introduce the trideuteromethyl group (CD3) with excellent levels of deuterium content.

Determination of relative sensitivity factor, sputtering rate, and detection limits of deuterium in deuterium ion‐implanted Zircaloy‐4 using secondary ion mass spectrometer

Zirconium‐based alloys are extensively used in the nuclear industry as materials for reactor core components. These alloys are used in fuel cladding and pressure tubes with 1H2O or 2H2O as the primary heat exchange fluid. Continuous usage of pressure tubes and fuel cladding inside the reactor results in heavy ingress of hydrogen (1H) or deuterium (2H), which gives rise to the formation of hydrogen (or deuterium) precipitates in the host of zirconium matrix. This is called hydrogen (or deuterium) embrittlement phenomenon. Therefore, determination of hydrogen or deuterium concentration periodically in zirconium alloy pressure tubes and cladding are crucial for safe operation of nuclear reactors. Hence, in this work, secondary ion mass spectrometry (SIMS) has been utilized to determine the relative sensitive factor (RSF), sputtering rate, and detection limits of 2H in 2H+ ion‐implanted Zircaloy‐4 sample. SIMS analysis has been carried out using O2+ and Cs+ primary ion beams. Depth profiles of various elemental and molecular secondary ions have been monitored to determine the RSF values and detection limits of 2H in the sample under different primary ion beam analysis conditions. Sputtering rate under different analysis conditions has also been determined from the correlation between the projected range of 2H+ ions in Zircaloy‐4 sample determined from Stopping and Range of Ions in Matter (SRIM) software and the depth of the crater formed by primary ion beam bombardment process. The projected range of 2H+ ions in Zircaloy‐4 was estimated to be ~524.2 nm using the simulation carried out by SRIM software. The projected range, evaluated by SRIM software, was utilized for depth scale calibration of SIMS sputtered time profiles. The SIMS depth profiles were also calibrated by determining the depth of the SIMS crater by using optical depth profilometer. The values of range estimated by SRIM as well as optical profilometer were found to be in good agreement, within instrument uncertainty.

Reactive Alterations in Thymic Lymphocytopoiesis to Short-Term Decrease in Deuterium Content in the Body

We studied changes in thymic lymphocytopoiesis induced by a short-term decrease in deuterium content in the body. The experiment was performed on adult male Wistar rats receiving water with lower deuterium content [D]=10 ppm. Increased relative weight of thymus was found after 24 h of consumption. Flow cytometry revealed higher percentage of undifferentiated cells and mature T cells, especially cytotoxic T cells. Hence, lymphocytopoiesis in the thymus is highly sensitive to short-term decrease in deuterium body content. A decrease in the content of deuterium stimulates proliferation of lymphoblasts in the thymus and slows down migration of differentiated T cells. Enhanced generation of cytotoxic T cells under these conditions attests to the role of deuterium in selection of double-positive thymocytes. The revealed shifts are reactive, and their pattern can change later, which requires further research.

Hydrogen trapping at dislocations, carbides, copper precipitates and grain boundaries in a dual precipitating low-carbon martensitic steel

By using atom probe tomography to detect deuterium in a dual precipitating low carbon martensitic steel we provide insight into the relationship between hydrogen (H), carbon, and microstructural features. TiC and Cu precipitates were found to provide H trapping sites, however, dislocations without C were not observed to trap H. The order of trapping from highest to lowest concentrations of deuterium (D) is as follows: TiC decorated dislocations > high energy grain boundaries > low energy grain boundaries.

Crystal structure of deuteride phase of Nd-Ni alloy by X-ray and neutron diffraction

The hydrogen-absorbing alloys currently used in industry form residual hydrogen that reduces the alloy’s reversible hydrogen capacity, decreasing its useful life. RNi3 intermetallic compounds, which have a PuNi3-type crystal structure composed of MgZn2-type and CaCu5-type cells that exhibit structural change in relation to their hydrogenation properties, have been the focus of much research, but only a few of those reports focus on the interplay between residual hydrogen and alloy structure. Thus, this study seeks to clarify the residual hydrogen occupation mechanisms in MgZn2-type and CaCu5-type cells during the hydrogen absorption-desorption process. The structural changes and deuterium occupation in NdNi3Dx were investigated using X-ray diffraction (XRD) and neutron powder diffraction (NPD). Rietveld refinement was performed for NdNi3, NdNi3D2.6, NdNi3D3.2, NdNi3D4.0, and NdNi3D4.8, during the deuterium absorption-desorption process. The deuterium capacity reached 0.9 D/M at the first absorption process and 0.7 D/M of residual deuterium was formed after the first desorption at 248 K. For NdNi3D2.6 (phase II), the residual deuterium contents of MgZn2-type and CaCu5-type cells were determined to be 1.0 D/M and 0.4 D/M, respectively. The residual deuterium preferred the deuterium site in the MgZn2-type cell. The deuterium capacity was 1.2 D/M in the first absorption process at 213 K and the residual deuterium was 1.0 D/M at the end of the first desorption. The severe peak broadening observed in the XRD and neutron diffraction patterns of NdNi3D4.0 and NdNi3D4.8 indicate that the deformation of the metal sublattice of the deuteride phase was deformed over 0.8 D/M.

Improving the Quantification of Deuterium in Zirconium Alloy Atom Probe Tomography Data Using Existing Analysis Methods

Abstract Zirconium alloys are common fuel claddings in nuclear fission reactors and are susceptible to the effects of hydrogen embrittlement. There is a need to be able to detect and image hydrogen at the atomic scale to gain the experimental evidence necessary to fully understand hydrogen embrittlement. Through the use of deuterium tracers, atom probe tomography (APT) is able to detect and spatially locate hydrogen at the atomic scale. Previous works have highlighted issues with quantifying deuterium concentrations using APT due to complex peak overlaps in the mass-to-charge-state ratio spectrum between molecular hydrogen and deuterium (H2 and D). In this work, we use new methods to analyze historic and simulated atom probe data, by applying currently available data analysis tools, to optimize solving peak overlaps to improve the quantification of deuterium. This method has been applied to literature data to quantify the deuterium concentrations in a concentration line profile across an α-Zr/deuteride interface.

Measurement of deuterium concentration in heavy water utilizing prompt gamma neutron activation analysis (PGNAA) in comparison with MCNPX simulation results

Considering the importance of deuterium in nuclear science including medical and industrial researches such as (BNCT) and nuclear reactors respectively, it is important to study various possible ways in addition to common methods for measuring its concentration. This study is an effort to measure deuterium concentration using PGNAA. The main idea is to calculate the area under 2.23 MeV gamma-rays photo peak resulting from neutron collision with Hydrogen atoms which are in mix with deuterium in samples. The study carried out by both simulation and experiment. Monte Carlo MCNPX2.6 code has been used for simulation and based on its acceptable results an experimental setup has been arranged. The coordination of results was in the range of R = 0.99 and R = 0.98 in simulation and experiment respectively. The accuracy of the study has been investigated by measuring the concentration of an unknown sample by both PGNAA and Fourier transform infrared spectroscopy (FT-IR) methods in which there were acceptable correlation between these two methods.

ЭФФЕКТ СНИЖЕНИЯ ТОКСИЧНОСТИ ФТОРХИНОЛОНОВ В СРЕДАХ РАСТВОРЕНИЯ РАЗНОЙ ПРИРОДЫ

Abstract. The purpose of this work is to evaluate the effectiveness of reducing the toxicity of fluoroquinlone (FTQ) drugs. For this the Spirotox original method was used in combination with the model scheme of the enzymatic kinetics of Michaelis-Menten. Dissolution media of different nature and isotopic composition are considered as factors contributing to the reduction of the FTQ toxicity. The nature of a solvent with a different D/H ratio demonstrates the development of the kinetic isotope effect (KIE) during the course of biochemical processes ("light" water), as well as detoxifying properties (a complex of humic and fulvic acids, HFA). By the method of tangents to the graph of the“tL,sec – -lgC” function, an intersection with the ox axis corresponding to Ctox, mol·L-1 was found at the approximation point. It has been shown that the FTQ dilution with "light" water (with a reduced deuterium content, ≤ 1 ppm) or a complex of humic and fulvic acids contributes to an increase in the cells lifetime by 3-4 times compared with purified water. When selecting the highest value of the Pearson coefficient from the graphical dependence "tL – 1/Ln", as a result of extrapolation to x=0 and y=0, the enzymatic kinetic parameters were determined – Keq (by the negative segment on the ox axis) and fm (by the segment on the oy axis). The obtained values were for levofloxacin drug: Keq =3.99 ·10-2 mol·L-1, fm= 2.17 ·10-3 s-1 (dilution with purified water), Keq=1.12·10-1 mol·L-1, fm=4.62·10-2 s-1 (dilution with "light" water), Kp=6.37·10-1 mol·L-1, fm=1.61·10-2 s-1 (dilutions with HFA); for moxifloxacin drug: Keq=3.87·10-3 mol·L-1, fm= 7.87 ·10-2 s-1 (dilution with purified water), Keq=7.50·10-3 mol·L-1, fm=1.75·10-2 s-1 (dilution with "light" water), Keq=9.89·10-8 mol·L-1, fm=2.06·10-2 s-1 (dilution with GFC). The results obtained can be used in the pharmaceutical industry for the manufacture of medicines with an improved pharmacological profile.

Possibility to Alter Dynamics of Luminescence from Surface of Polymer Membrane with Ultrasonic Waves.

The temporal dynamics of luminescence from the surface of Nafion polymer membranes have been studied. In fact, the polymer membrane was soaked in liquids with different contents of deuterium. The test liquids were ordinary (natural) water (deuterium content equal to 157 ppm) and deuterium-depleted water (deuterium content is equal to 3 ppm). Simultaneously with the excitation of luminescence, the Nafion plate was irradiated with ultrasonic pulses, having a duration of 1 μs. The ultrasonic waves were generated with different repetition rates and amplitudes, and irradiated the surface of Nafion in the geometry of grazing or normal incidence. Luminescence regimes were studied when the membrane was irradiated with one ultrasonic wave (one piezoelectric transducer) or two counter-propagating waves (two piezoelectric transducers). It turned out that ultrasonic waves, which fall normal to the membrane interface, do not affect the dynamics of luminescence. At the same time, in the case of ultrasonic irradiation in the grazing incidence geometry, sharp jumps in the luminescence intensity occur, and the behavior of these jumps substantially depends on the mode of irradiation: one or two piezoelectric transducers. This allows for control of the dynamics of luminescence from the polymer surface. In accordance with this model, the possibility of altering the luminescence dynamics is due to the effect of unwinding the polymer fibers from the surface toward the liquid bulk upon soaking. It is important that such unwinding does not occur in deuterium-depleted water, which was confirmed in a direct experiment with dynamic light scattering from polydisperse aqueous suspensions of Nafion nanometer-sized particles; these suspensions were prepared in ordinary water and deuterium-depleted water. Thus, ultrasonic irradiation affects the dynamics of luminescence only when Nafion is swollen in ordinary water; in the case of deuterium-depleted water this effect is missed.

Quantitative analysis of hydrogen isotopes in hydrogen storage material using laser-induced breakdown spectroscopy

• The scanning-coaxial LIBS system is set up for in-situ measurements in fusion reactors. • Titanium foil with different hydrogen and deuterium contents is prepared and determined. • Hydrogen isotopes are analyzed quantitatively using the internal standard method (ISM) and the calibration free method (CF-LIBS). • The single sample correction calibration free method (SSCCF) is applied to improve the accuracy. The accurate determination of hydrogen isotopes in materials is always a challenge for laser-induced breakdown spectroscopy (LIBS). In this study, the content of hydrogen isotopes in hydrogen storage materials is quantitatively analyzed by LIBS using the internal standard method (ISM) and the calibration-free method (CF-LIBS), respectively. Based on the self-built LIBS system, the concentrations of hydrogen and deuterium in titanium hydride with various stoichiometric ratios are quantitatively analyzed. The local thermodynamic equilibrium (LTE) conditions of the plasma are evaluated by the calculation results of the plasma temperature and density: the plasma temperatures are 16000 ± 1000 K calculated by Boltzmann diagram of titanium, and the plasma electron densities are about 10 22 m −3 calculated by the H α line of spectra. Through integral intensity correction, the correlation coefficient of the calibration curves of hydrogen and deuterium is successfully increased by 3% in the internal standard method; The single sample correction is used in CF-LIBS to improve the accuracy of the measurement of hydrogen isotopes in titanium hydride, and the calibration results demonstrate that the average absolute errors are 8.3% and 3.2% for hydrogen and deuterium. We also compare the calculated contents of hydrogen isotopes in titanium hydride by integral intensity correction internal standard method (IICIS) and single sample correction calibration-free method (SSCCF). The SSCCF increases the accuracy of the hydrogen isotope contents compared with CF-LIBS in the range of 20 to 55 at.%. The results are not as precise as the IICIS but meet the ITER requirements in a way. The results provide a valuable reference for the precise measurement of hydrogen isotope content in materials for applications in hydrogen energy, nuclear energy, and nuclear technology.

A convenient strategy to prepare supramolecular deuterated polymers

Deuterated polymers have been widely used in many researches, such as small-angle neutron scattering, NMR studies and inertial confinement fusion, but the types of deuterated polymers that can be used are still very limited. In this work, we introduce the concept of supramolecular polymers to develop new deuterated materials toward applications in inertial confinement fusion. To this end, cycloocene- d 14 with deuterium content of 97% is prepared and has been further used as monomers. Deuterated macromonomers with 2-ureido-pyrimidinone as end groups are prepared via either a multistep or a “one-pot” approach. The supramolecular deuterated polymers are formed by the hydrogen-bonding mediated supramolecular polymerization of the macromonomers. With the obtained supramolecular deuterated polymers, uniform polymer shells toward ICF experiments are prepared by the microfluidic technique and solvent evaporation method. • A convenient synthetic approach to prepare supramolecular deuterated polymers with high deuterium contents toward ICF applications has been established. • The CTA with supramolecular motif UPy as end-groups can be regarded as supra-CTA during a ROMP reaction. • By a microencapsulation technique, uniform polymer shells toward ICF experiments can be prepared from the supramolecular deuterated polymers.

Determining the fuel ion ratio for D(T) and T(D) plasmas at JET using neutron time-of-flight spectrometry

The fusion fuel ion ratio, , is an important plasma parameter that needs to be tuned to maximize the power of a tokamak type fusion reactor. It is recognized as a parameter required for optimizing several ITER operating scenarios, and will likely be continuously monitored in future high-performance fusion devices such as DEMO. Tritium was recently introduced in the Joint European Torus (JET) plasma for the first time since the 1997 DTE1 and 2003 TTE campaigns, enabling the possibility to investigate fuel ion ratios. We present a method for measuring using neutron time-of-flight (TOF) spectrometry. By fitting the measured neutron spectral features, the relative reaction rate intensities between different ion species can be inferred, from which the fuel ion ratio can be extracted for a corresponding modeled reactivity. Unlike previous measurements of using neutron spectrometry, we utilize the neutron energy continuum produced in the three-body TT reaction to determine the fuel ion ratio for plasmas with large concentrations of tritium. Furthermore, the use of neutron TOF spectrometry has never previously been demonstrated for evaluating . The method is applied to TOF spectra acquired with TOFOR (JET name KM11) and shown to be consistent with the optical JET diagnostic KT5P which uses optical spectroscopy of a modified Penning gauge plasma to measure tritium and deuterium concentrations in the divertor exhaust gas.

Isotope removal experiment in JET-ILW in view of T-removal after the 2nd DT campaign at JET

A sequence of fuel recovery methods was tested in JET, equipped with the ITER-like beryllium main chamber wall and tungsten divertor, to reduce the plasma deuterium concentration to less than 1% in preparation for operation with tritium. This was also a key activity with regard to refining the clean-up strategy to be implemented at the end of the 2nd DT campaign in JET (DTE2) and to assess the tools that are envisaged to mitigate the tritium inventory build-up in ITER. The sequence began with 4 days of main chamber baking at 320 °C, followed by a further 4 days in which Ion Cyclotron Wall Conditioning (ICWC) and Glow Discharge Conditioning (GDC) were applied with hydrogen fuelling, still at 320 °C, followed by more ICWC while the vessel cooled gradually from 320 °C to 225 °C on the 4th day. While baking alone is very efficient at recovering fuel from the main chamber, the ICWC and GDC sessions at 320 °C still removed slightly higher amounts of fuel than found previously in isotopic changeover experiments at 200 °C in JET. Finally, GDC and ICWC are found to have similar removal efficiency per unit of discharge energy. The baking week with ICWC and GDC was followed by plasma discharges to remove deposited fuel from the divertor. Raising the inner divertor strike point up to the uppermost accessible point allowed local heating of the surfaces to at least 800 °C for the duration of this discharge configuration (typically 18 s), according to infra-red thermography measurements. In laboratory thermal desorption measurements, maintaining this temperature level for several minutes depletes thick co-deposit samples of fuel. The fuel removal by 14 diverted plasma discharges is analysed, of which 9, for 160 s in total, with raised inner strike point. The initial D content in these discharges started at the low value of 3%–5%, due to the preceding baking and conditioning sequence, and reduced further to 1%, depending on the applied configuration, thus meeting the experimental target.

Blocking the Increase of Intracellular Deuterium Concentration Prevents the Expression of Cancer-Related Genes, Tumor Development, and Tumor Recurrence in Cancer Patients.

The possible role of the naturally occurring deuterium in the regulation of cell division was first described in the 1990s. To investigate the mechanism of influence of deuterium (D) on cell growth, expression of 236 cancer-related and 536 kinase genes were tested in deuterium-depleted (40 and 80 ppm) and deuterium-enriched (300 ppm) media compared to natural D level (150 ppm). Among genes with expression changes exceeding 30% and copy numbers over 30 (124 and 135 genes, respectively) 97.3% of them was upregulated at 300 ppm D-concentration. In mice exposed to chemical carcinogen, one-year survival data showed that deuterium-depleted water (DDW) with 30 ppm D as drinking water prevented tumor development. One quarter of the treated male mice survived 344 days, the females 334 days, while one quarter of the control mice survived only 188 and 156 days, respectively. In our human retrospective study 204 previously treated cancer patients with disease in remission, who consumed DDW, were followed. Cumulative follow-up time was 1024 years, and average follow-up time per patient, 5 years (median: 3.6 years). One hundred and fifty-six patients out of 204 (77.9%) did not relapse during their 803 years cumulative follow-up time. Median survival time (MST) was not calculable due to the extremely low death rate (11 cancer-related deaths, 5.4% of the study population). Importantly, 8 out of 11 deaths occurred several years after stopping DDW consumption, confirming that regular consumption of DDW can prevent recurrence of cancer. These findings point to the likely mechanism in which consumption of DDW keeps D-concentration below natural levels, preventing the D/H ratio from increasing to the threshold required for cell division. This in turn can serve as a key to reduce the relapse rate of cancer patients and/or to reduce cancer incidence in healthy populations.

Изучение изотопного и химического состава глубинной воды озера Байкал

Introduction. Due to its natural composition, the deep water of Lake Baikal can be bottled without any conserving agents. The development of large-scale production of bottled Baikal water requires its detailed study in order to protect it from counterfeit and falsification. The purpose of this work was to study the isotopic and chemical composition of the deep water of Lake Baikal and offer indicators for its identification. Study objects and methods. The research included deep water of Lake Baikal, sampled at various points, the water from the Angara River, and the tap water from the cities of Irkutsk and Shelekhov. The tests were performed using a quadrupole ICP-MS mass spectrometer and a Delta V Plus isotope mass spectrometer with a GasBench II module. Results and discussion. All the water samples revealed fresh water with insignificant mineralization. As for salts, the deep water samples had a lower content of sodium and chlorides, as well as a higher content of silicon. As for metals, the deep water samples contained iron, manganese, copper, and zinc; in the tap water samples, these indicators were significantly higher. Unlike that of the Angara water samples, the isotopic profile of the deep water samples was somewhat “lighter”, both in the ratio of oxygen isotopes δ18O – by 0.73‰, and hydrogen δD – by 0.49‰. The tap water samples had a higher deuterium content. The content of oxygen isotopes (δ18O) in the tap water samples was close to that in the Angara samples. Conclusion. The complex physicochemical and isotope analyses expanded the list of identification indicators and made it possible to identify the deep water of Lake Baikal.

Cardiac Heart Rate Dependence on Mitochondrial Deuterium 2H Content

Mitochondrial cardiac ATP production efficiency in beef hearts has been known to decrease with increasing systemic deuterium 2H levels since the 1980’s. Recently ketogenic diets which are known to decrease deuterium levels in humans were found to decrease both the resting and exercise heart rates in a volunteer. Furthermore, resting heart rates were found to systematically vary with the deuterium content from the previous meal consumed by six volunteers. A cardiac model is proposed showing extreme sensitivity of heart rate on the deuterium loading of the ATP synthase nanomotors. A predicted increase in heart rate by 28% is expected with a 5% decrease in ATP production. This finding strongly suggests that high deuterium levels in the fatty acids contribute to the diastolic dysfunction in heart failure not already attributed to direct structural damage, i.e., heart failure with preserved ejection fraction.