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Target Efficiency Measurements at the AGS
Two methods for measuring target efficiencies are briefly discussed. The second method puts an upper bound on the efficiency and permits observation of instantaneous efficiency, thereby aiding location of losses. Measurements agree well with conventional radiochemical values.
Technical Discussion of Brookhaven Off-Site Personnel Monitoring Service
A number of questions have arisen in regard to the interpretation of personnel monitoring results reported to users of the Brookhaven neutron monitoring service. The original announcement was rather brief and did not contain most of the technical characteristics upon which an evaluation of results must be based. The following paragraphs have been composed with the hope that they will clarify the meaning of the exposure reports.
The Temperature Dependence of Birefringence in Irradiated Polyethylene
Technical report on a study where the birefringence of irradiated polyethylene was observed as a function of temperature. The data is consistent with a mechanism in which crosslinking limits the growth and annealing of crystallites. Crosslinks formed in material which was oriented at the time the crosslinks were formed, results in an oriented gel. This effect explains the birefringence and the persistence of nucleation sites at high temperatures.
Temperature Measurements on a 420-foot Tower
Continuous measurements of the ambient air temperature have been made on a 420-ft tower at Brookhaven for nearly four years. Operational requirements associated with reactor operations have established a need for equipment which is durable, stable and accurate. The sensing elements consist of Leeds and Northrup resistance thermometers (Thermohms), housed in radiation shields and aspirated by a central pump. A twelve-point, triple-range recorder effects the successional measurement of temperature at each level. Two model R Leeds and Northrup instruments record the differences in temperature between the top of the tower and its base, and between the top and an intermediate level. Numerous tests and experiments have been conducted to determine the characteristics of the Thermohms, radiation shields, recorders, and the aspirating system. A technique is described for calibrating the tower thermometers and their associated recorders. Brief mention is made of the importance for lightning protection on a high tower.
A Test for the Influence of Radiation Decomposition on Retention in the Szilard-Chalmers Reaction
It has been considered possible that the low-level radiation decomposition normally encountered in the neutron bombardment of organic halides might have some influence on the properties of halogen activity retained in organic form. The decrease in retention produced by chlorine and the increase produced by allyl chloride appears to be experimentally identical under the three conditions of bombardment used.
Theoretical Analysis of the Exponential Experiment in Natural Uranium
Methods of calculating the "Snell Experiment" (the exponential experiment in natural uranium) are examined. It is found that integral transport theory is required for accurate predictions. The effect of spatial transients upon measured quantities is studied and it is found that experiments have not been done in a large enough mass of uranium to achieve an asymptotic neutron distribution. However deviations from the asymptotic values of integral quantities are not large and corrections are calculated and applied to recent experiments. It is shown that the use of recent cross section data improves the agreement between theory and experiment. The relaxation length and all spectral indices are in fairly good agreement except for Np237 to U238 average fission cross section ratio.
Theory of Final State Interactions
Using requirements of analyticity and the unitarity of the S-matrix we obtain the dependence of a transition amplitude on the invariant mass of two particles strongly coupled to other two particle channels. As an example, we consider the production of a Σπ state near the Y*₀ resonance assuming it is coupled to a KN state in an s 1/2 state.
Theory of Point Defect Annealing in Metals
The kinetics of the annealing of point defects, either by migration to sinks or by recombination, is complicated by the occurrence of a variety of simultaneous reactions. An extensive theoretical study of annealing processes is in progress at Brookhaven based on the isolation and combination of simple kinetic steps. When analytic solutions could not be found, computer solutions have been used to obtain useful approximations and to determine their regions of validity. Two migration reaction schemes have been studied; the simultaneous annealing of single and divacancies, and the annealing of single vacancies with impurity trapping. These recombination reactions and interstitial migration to sinks, di-interstitial formation, and interstitial trapping at impurities.
Thermal Conductivity of Graphite
Technical report outlining the differences in conductivity of AGOT graphite and AGHT graphite.
The Thermal Decomposition of Irradiated [alpha] Lead Aside
This report studies the thermal decomposition of unirradiated and heavily reactor irradiated colloidal [alpha] - PbH6.
The Thermal Decomposition of NaBrO₃, Part 1: Unirradiated Material
The thermal decomposition of polycrystalline NaBrO₃ has been studied in the temperature range 323–430°C. The only products are NaBr and Oxygen. Like KBrO₃, the reaction begins essentially on surfaces by the rapid formation of an interface and is followed by the penetration of this interface into the crystallite. The melting of a eutectic formed between the product NaBr and the parent material causes a marked increase in rate over certain temperature ranges. This is evident as a very sharp discontinuity on the Arrhenius plot. Evidence also exists for reaction along other routes such as at dislocations and other defects. Some of these conclusions are borne out by results with finely ground material.
The Thermal Decomposition of NaBrO₃, Part 2: Irradiated Material
Studies of the thermal decomposition of NaBrO₃ reported in Part I have been extended to include material pre-irradiated with Co₆₀ y-ray and reactor irradiations. The primary effect of the irradiation appears to be an enhancement of the melting rate of the eutectic formed between NaBrO₃ and the product NaBr, and is accompanied by an enhanced decomposition rate. The conclusion reached with unirradiated material that alternate decomposition routes exist such as at dislocations and other defects is strengthened.
Thermodynamics of Fused Salt Mixtures From EMF Measurements. The Systems NaCl-KCl, NaCl-MgCl2, and NaCl-CeCl3.
The following cells were operated at 820°C: [equations not transcribed] where the over-all reaction in each cell is simply the transfer of NaCl from pure NaCl to the mixtures of the right hand compartment. The porcelain acts as a pure sodium ion conductor in these cells. The relative partial molar free energy of mixing for sodium chloride, FMNaCl, is given by [equation not transcribed] where E is the EMF of the cell. Results are given over the entire composition range in each system and compared with previous measurements from other sources. Other thermodynamic quantities are calculated from the results. Experiments using a H2, HCl mixture in place of Cl2 are discussed, as well as the extension of the measurements to other systems.
Thermodynamics of Solutions of Actinides and Fission Products in Bismuth
This report reviews the published work on the thermochemistry of the liquid alloys of bismuth with Th, Pa, U, and Pu and the high-yield fission products, and presents in a unified form the authors' own results in this field.
Time Dependence of Space Charge Beam Losses in the Cosmotron
An investigation was made of Cosmotron intensity versus time through the entire time interval from the beginning of injection to the completion of r-f capture. The induction electrode signal was used for the instantaneous measurement of beam intensity. Oscilloscope displays of the signal were photographed and traced. Base lines were filled in on the tracings and the area of the pulses measured with a polar planimeter. It was found that the relation losses of beam intensity increase with injection intensity (total injected charge), and that most of the losses take place in the time interval between the end of injection and the completion of the first synchrotron oscillation
A Time-Shared Computer Data Collection System at the Brookhaven Graphite Research Reactor
The increasing complexity of the data of nuclear physics has led to widespread interest in the possibility of utilizing a digital computer for on-line data collection. Through the combined efforts of the Instrumentation Division and the Neutron Physics group at Brookhaven such a system has been placed into operation. Several features of this system are believed to be unique and of interest to research groups centered about a major facility like a reactor or an accelerator.
Tissue Distribution and Storage Forms of Vitamin B12 Injected and Orally Administered to the Dog
Previous attempts by the present authors to compare the behavior of orally administered vitamin B12 with that of injected material have been inconclusive. Thus, 30 days after administration to normal humans, 0.19% of a tracer amount (0.5 μg) of injected radioactive vitamin B12 is excreted per day; and in an independent study, the eventual daily output was found to be 0.23% of a 3 μg dose. By contrast the total excretion rate of normal vitamin B12 from body stores appears to be only ≈0.03% per day. Such a divergence may result from incomplete mixing of radioactive vitamin B12 and body stores of the vitamin. Alternatively it may actually reflect the functioning of different compartments attending the several modes of administration involved. The possibility of degradation or transformation of vitamin within tissues and organs must also be considered.
Total Cross Sections for K Mesons and π Mesons on Protons and Deuterons between 2.5 and 6 BeV/c
Recent measurements of the pion-proton total cross section, taken with small statistical errors, have shown the existence of two new maxima in the momentum range between 2 and 3 BeV/c. Measurements of comparable statistical accuracy, covering the momentum range from 2.5 to 8 BeV/c are reported in the present paper. In addition to the total cross sections for π± mesons on protons, their total cross sections on deuterons have also been determined. Some data were also taken on the total cross sections for K+ mesons on protons and deuterons and for K- mesons on protons.
Total Neutron Average Cross Sections in the keV Region and the Optical Model
Many workers have recently attempted to evaluate the P-wave strength function from a measurement of average capture cross sections or average total cross sections in the kiloelectron volt region. The primary interest of these measurements has been to determine the strength of the spin-orbit potential in the optical model. In view of the interest in determining the size of the spin-orbit coupling and in view of the considerable disagreement group has undertaken to measure the average total neutron cross sections from 10 to 100 keV in the region of the P-wave giant resonance. The following elements were studied: Nb, Mo, Rh, Ag, Cd, and In. The wok was carried out at the BNL-AECL fast chopper facility at Chalk River, using an 88-meter flight path and a nominal resolution of 15 nsec/meter.
Tracers, Transfer Through Membranes, and Coefficients of Transfer
From abstract: "The rate of flow of a tagged species of a material substance through a permeable membrane is proportional to the rate of flow of the substance itself when, and only when, the species mol [sic] fraction of the substance is the name on both sides of the barrier. The ratio of the osmotic transfer coefficient of a substance in a particular barrier to the exchange coefficient, determinable with a tracer, is greater than one."
Trajectories for a Rectangular Magnet with Uniform Field
In connection with the design of a hodoscope system for the momentum analysis of secondary particles from a target bombarded by monoenergetic particles, it has been considered to use a large-aperature rectangular magnet with uniform field, and a hodoscope set of counters behind the magnet after a suitably long flight path of the particles. For accurate calibration of the momentum of the particles, it will probably be necessary to map very completely the field inside the magnet and the fringing fields at the entrance and exit boundaries, in order to calculate typical trajectories as a function of the position of the particle path at the entrance to the magnet, and the entrance angle and particle momentum. Nevertheless, for the sake of orientation, it may be useful to obtain the projections of the trajectory in the horizontal and vertical planes in the approximation that the effect of the fringing field can be represented by adding a correction to the length of the magnet and assuming that the field is uniform over the distance of the total effective length, and is zero outside the effective field boundaries. For treatment of the vertical motion, we will also assume that the object (source) lies in the median plane of the magnet. This condition will be approximately satisfied in the important practical case that the source is a target which is small in the vertical direction and from which the secondary particles are emitted.
Transport, Homeostasis and Specificity in Trace Metal Metabolism
A working definition of homeostasis is the following: the sum total of the processes which maintain a steady level of various substances or functions within a living baby. Our own concern will be with the homeostasis of trace metals. I will begin with a slide which shows the total body concentration of various metals, including "trace" ones. Only metallic constituents which play a role in the maintenance of the body's structure and function are shown. The essential trace metals among them are represented by black bars. Iron is both black and white. Indeed, if one excludes the fixed sequestered iron of myoglobin and of hemoglobin, one is left with a trace fraction of iron about which I will be talking later on. Note that the scale is logarithmic, indicating that the concentrations of essential metals in the body fall off sharply and smoothly.
Transport of FissionProducts Through the Soil Following Injection From a Well and Methods Used for Removal
In the summer of 1960 one of the little used wells on the Brookhaven National Laboratory site became accidentally contaminated with radioactive material. The contamination was discovered during a routine sampling of all wells in the waste disposal area, so there was a period of several weeks between the time of discharge.
Triosephosphate Dehydrogenase from Plant Tissue
Plant tissue contains two triosephosphate dehydrogenases, one using TPN as cofactor, the other using DPN. The leaves possess both enzymes while the roots and seeds possess only the DPN enzyme. Only the purification of the TPN enzyme will be described.
Tumor Induction by an IAA-Kinetin Interaction in an Nicotiana Hybrid
Technical report describing "the interaction of IAA, kinetin and GA upon tumor induction in Nicotiana hybrids." from the abstract.
Twin Channel Count Integrator (EH1-503)
Report issued by the Brookhaven National Laboratory discussing a twin channel count integrator. As stated in the introduction, "an accurate and stable recording ratemeter, designed to present the data from two counters on one strip chart recorder, is described" (p. 1). This report includes tables, and illustrations.
Two Lectures on the Magnetic Scattering of Neutrons
In these lectures we will discuss some examples of information about magnetic properties of solids which can be obtained by neutron scattering. We consider a scattering process in which a neutron with wave vector k and spin σ is incident upon a solid in state q>. (Here q stands for all of the quantum numbers which describe the state of the solid, such as spin and orbital electronic states, phonon numbers, etc.) After interacting with the solid, the neutron goes off with wave-vector k' and spin σ', leaving the solid in state q'>. In performing an experiment of this sort one does not usually observe the initial and final spin states of the neutron or the initial and final states of the solid. We must then sum over all possible final states and average over all initial states.
Two New Nucleotides from Rabbit Liver
Two new substances, which appear to be polyphosphate derivatives of adenine nucleotides, have been obtained from trichloracetic acid extracts of rabbit liver. They appear to be chemical entities whose properties do not correspond with those of any of the compounds previously found in such extracts. One contains adenine and phosphate in the ratio of 2 to 3, and a carbohydrate derivative. The other compound contains adenine, pentose (presumably ribose), and phosphate in the ratio of 1:1:2. Both compounds were obtained in the elution of purine nucleotides from Dowex 1 ion exchange resin by 0.01M HCl, according to the procedure of Cohn and Carter (1). They appear between the fractions containing adenylic acid and adenosine diphosphate.
The Ultraviolet Sensitivity of Frozen Phage
Recent reports (1, 2, 3, 4, 5) suggest that the crystalline structure of ice permits unusual forms of energy relationships and that the structured state of water may be of importance in the whole cell. A number of biologically interesting compounds show significantly altered responses to the excitation energy of ultraviolet light in ice as compared to the liquid state. This paper describes the effect of a change in phase state on a biologically active nucleoprotein, a bacteriophage particle. Phage is found to be much more sensitive to inactivation by ultraviolet light when irradiated in frozen aqueous suspension than when irradiated at room temperature (7): the sensitive target appears to be the phage DNA.
The Unique Brookhaven National Laboratory Cosmotron Motor Generator Foundation
An interesting dynamic foundation problem was recently posed at Brookhaven National Laboratory in supplying the main magnet power for the three billion electron volt (3BEV) Cosmotron; at present the highest energy particle accelerator known to be in operation.
Unit for Continuous Separation of U233 From Thorium Fluoride
Technical report outlining a preliminary design for carrying out the process of producing U233 from Th232.
Uranium-Bismuth In-Pile Corrosion Test Loop: Radiation Loop No. 1
Report issued by the Brookhaven National Laboratory discussing uranium-bismuth corrosion test loops. Design, construction, and operation of the test loops are presented. This report includes tables, illustrations, and photographs.
Use of a Digital Computer in the Development of a Positron Scanning Procedure
The problem to be discussed originates in our interest in the diagnosis and treatment of brain tumors. It has been established by others that some positron-emitting radioactive isotopes, in particular Arsenic-74 and Copper-64, can be causal to localize in brain tumors and thus to serve as agents for locating the tumors. Although other kinds of radioisotopes have also been used successfully in locating tumors, positron emitters have some especially attractive features. Their use is based on the principle that a positron, or positively charged electron, is a form of "anti-matter," and when it encounters an ordinary negatively charged electron both are annihilated, giving rise to two gamma rays that are emitted in opposite directions. Such an event is detectable through the use of coincidence counting. The data for which the method of analysis is to be discussed in the present paper is generated by a device using the coincidence counting method with multiple detectors in an arrangement potentially suitable for three-dimensional localization of brain tumors.
Use of a Portable Whole-Body Counter to Measure Internal Contamination in a Fallout-Exposed Population
Technical report regarding the evaluation of body burdens of radionuclides in large populations in a large-scale survey.
The Use of Activated Charcoal Iodine Monitors During and Following a Release of Fission Product Iodines
The present core of the Brookhaven Graphite Reactor consists of some 4900 highly enriched uranium fuel loaded in 615 horizontal fuel channels passing through a 25 foot cube of graphite moderator and reflector. The core is divided into two halves (north and south) by an 8 cm. wide vertical gap in the center of the graphite. The cooling air enters the reactor through inlet filters, at the rate of 270,000 CFM, passes into the central gap and flows bi-directionally through the north and south halves of the core. It then enters the collecting plenums and flows into the north and south ducts. The air is first monitored by the north and south exit air monitors located within the pile building. These are moving filter tape monitors with beta scintillation detectors. They are essentially operational monitors and are maintained by reactor operations. They are essentially operational monitors and are maintained by a reactor operations. The air then passes through the exit air filters, heat exchanger, venturi and on to the fan house where the north and south ducts join. After the fan house the air is monitored by Argon-41 by a Kanne ion chamber syste.
Use of an Analogue Computer in Studies of Strontium and Calcium Metabolism in Man
Although strontium is not normally a significant body component, its metabolism is currently of great interest because of its similarity to calcium metabolism and because of the hazards or potential hazards of strontium isotopes as fallout constituents. The data to be discussed here are part of a study being described is greater detail elsewhere and which was undertaken to help quantify the degrees of similarity and differences between the behavior of calcium and strontium. The analogue computer described in the preceding paper was used in the analysis of the data.
The Use of Low Energy Radioactive Isotopes in The Examination of Paintings on Thin Supports
The importance of the examination of paper and textile supported art objects by means of low energy X-rays has been ably discussed in the preceding papers of this session. The apparatus used for such radiography, however, has tended to be both expensive and confined to laboratory use. A lack of mobility arises from the weight and size of X-ray apparatus and the fact that its installation frequently requires shielding and special electric power lines. An inexpensive radiographic apparatus that required no special installation or external power and is small and light enough to be easily portable should be quite useful.
Use of Neutron Irradiations in the Brookhaven Mutations Program
In brief, these facilities consist of a 250 KvP X-ray generator; two areas of a research reactor, one a well thermalized unit of moderate capacity and a larger area with a mixed thermal and fast neutron distribution, all of which are used for brief, acute exposure. A 10 acre field, currently with almost 4000 curies of cobalt 60, serves to irradiate entire plants for either short or long periods of time. Recently, the flux density of the thermal column was increased by a factor of 5 over the original density. This was accomplished by lowering the thermal column 12 inches deeper into the reactor shield. Fast neutrons at this higher flux density are also available to the cooperator. An additional facility available to the program is the array of kilocurie gamma sources in the Nuclear Engineering Department of Brookhaven National Laboratory.
The Use of Radioactive Bromide and Chloride to Measure Extracellular Fluid
During the last year we have been attempting to increase our understanding of the significance of the various dilution methods used to measure the extra-cellular fluid. When the dilution methods were first proposed to obtain a measure of the extracellular fluid volume, it was hoped that an agent could be found which would distribute uniformly and exclusively throughout this compartment, which would approach equilibrium rapidly, and which could be measured by simple and accurate procedures. We have turned our attention chiefly to the methods themselves using dogs and non-edematous adults as subjects.
The Use of Tritiated Thymidine in the Study of Tissue Activation During Germination in Zea Mays L.
The transition from dormancy to growth in plant seeds has been the topic of many biological studies (1,2). Of particular interest to the radiobiologist are the dramatic changes in radiosensitivity occurring soon after the soaking of the seeds (3). These changes are thought to be associated with the commencement of proliferative activity. The recently developed method of labeling DNA with tritiated thymidine allows analysis of proliferative activity in greater detail than was heretofore possible. In the present study, uptake of tritiated thymidine and mitotic counts were used to determine the sequence of activation of proliferation in tissues or organs of the germinating corn embryo.
Vapor-Liquid Equilibria of Methanol-Carbon Tetrachloride in Solutions of Low Methanol Concentration
The vapor-liquid equilibria of solutions 0.0002 to 1.0 mole fraction methanol in carbon tetrachloride at 10, 20, 30, 40 and 50°C have been examined. The equilibrium vapor and liquid compositions and the total pressure above these solutions at the five temperatures are reported. The "pure" vapor pressure of methanol, [unable to transcribe] (a function calculated from the quotient Pa/Na of partial pressure of methanol Pa and mole fractions of methanol in the liquid Na), and the calculated values of the heat of vaporization of methanol both conclusively indicate that in solutions more dilute than 0.001 mole fraction methanol there still exists strong intermolecular attraction. This interaction is attributed to the existence of methanol dimers. A value of 7.6 to 11.2 kcal/mole is estimated for the dissociation of the dimer; this is the energy of the hydrogen bond if there is one hydrogen bond per dimer, and if there are two hydrogen bonds per dimer the energy of the bond is one-half this value.
Vapor Pressures of Isotopic Molecules
It is apparent that major progress has been made both in the experimental and theoretical study of the vapor pressures of isotopic molecules in the last five years. Vapor pressure measurements are being made in different laboratories by different methods which agree with one another within a few hundredths of one percent. The theory has advanced to the point where a large body o experimental data can be systematized and understood. Quantitative calculations have been carried out which verify the mass, temperature, and potential energy dependence aspects of the theory. An old subject has been revived by advances in modern experimental and theoretical methods and is now useful for the study of quantum effects and structural effects in liquids and solids.
A Versatile Bubble-Chamber Track Measuring Stage
Technical report describing a bubble chamber film track measuring stage designed for maximum versatility that was build at Brookhaven National Laboratory. The report includes photographs and diagrams of the device.
Vitamin B₁₂ Turnover in Polycythemia and Leukemia
Both vitamin B₁₂ and folic acid are required for blood cell formation and normal bone marrow function, but it is not known if the functional state of the bone marrow influences the metabolism of these vitamins. It is therefore of interest to study the turnover of vitamin B₁₂ in two conditions where blood cell production is allegedly increased. Radiovitamin B₁₂ appears to be more rapidly excreted by patients with chromic myelocytic leukemia and polycythemia vera than by comparison patients without blood dyscrasias.
Wall and Bulk Temperatures for Fluids Flowing in Concentric Annuli
From introduction: "This brief paper deals with the subject of radial temperature differences for heat transfer to fluids flowing through concentric annuli under the following conditions and assumptions: a. constant heat flux; b. fully-established turbulent flow; c. heat transfer through inner wall only; d. physical properties independent of temperature."
Wave Functions for Antishielding Factors of Ions and for the Electronic Polarisabilities of the Alkali Atoms
The purpose if this paper is to present tables of perturbed wave functions which have been obtained in three recent investigations: (1) wave functions v1'(nℓ→ℓ') which pertains to the perturbation of the d electrons of various ions as a result of the potential due to a nuclear quadrupole moment Q3 (2) wave functions v1',H(nℓ→ℓ) which represent the antishielding of the d electrons for a possible nuclear hexadecapole moment H; (3) wave functions u2'(ns→p) which pertain to the dipole perturbation of the valence (ns) electrons of the alkali atoms. Throughout this paper, the notation is the same as in a previous report in which a similar tabulation of perturbed wave function was made.
Wave Functions for Quadrupole Antishielding Factors
The purpose of this paper is to present tables of the perturbed wave functions which have been recently obtained in a calculation of the quadruple antishielding factors γ∞ for the Mn+2, Fe+3, Ga+3, and Ag+ ions. The wave functions v'1(nℓ-ℓ) which are tabulated represent the effect of the perturbation due to a nuclear quadruple moment Q on the wave functions of the outermost electrons of the ion core.
X-Ray Mass Determination of Unprocessed Photographic Emulsions
A method for measuring the thickness of unprocessed nuclear emulations based on X-ray absorption is described and discussed
Xenon Concentration Changes in Brain and Other Body Tissues of the Dog During Inhalation of the Gas
A study has been made of xenon concentration changes in brain and other body tissues of the dog during inhalation of radioactive xenon. The xenon concentrations of the thalamus, hypothalamus, caudate nucleus and medulla oblongata were similar and significantly higher than those of the cerebral parietal cortex at the two and six minute periods of inhalation. Whereas four of the five brain tissues studied were saturated within about six minutes, the cerebral parietal cortex may not be completely saturated even after a twenty minute period of inhalation of xenon at a constant tension. The xenon concentration of adrenal gland tissue rises rapidly and exceeds that of the brain tissues after about a ten minute period of inhalation. Kidney, liver and striated muscle absorb xenon more slowly than the other tissues studied.
Ytterbium and Terbium Dodecaborides
The synthesis of several rare earth dodecaborides, isomorphous with UB12 and ZrB12, and crystallographic data for these phases were reported recently. The unit cells are face centered cubic with four formula weights of MeB12 per unit cell; the structures may be visualized in terms of boron atoms linked in a rigid three-dimensional network, with the metal atoms in large cubo-octahedral holes.
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