bluuebunny/crossref_metadata_2025 huggingface dataset:
An Apparatus for Low Voltage Nuclear Research
Authors: Haworth L. J. , King L. D. P. , Zahn C. T. , Heydenburg N. P.
Published: February 2005

An apparatus designed for nuclear studies at energies up to somewhat in excess of 300 kv is described. The potentials are derived from a voltage quadrupling circuit using laboratory constructed rectifiers and condensers. The accelerating tube, of the cascaded type, and its accompanying ion source furnish steady, well-focused proton beams. Effective proton intensities of 12, 40, and 60 microamperes are available in the beams of ionic masses 1, 2, and 3 respectively. Voltages are measured by a resistance voltmeter which has been calibrated to an accuracy of a few tenths of one percent. Certain peculiarities of the ion source which affect the homogeneity of the ion energies are discussed.
A Calibrated Source of High Frequency Potential
Authors: Githens Sherwood
Published: February 2005

The difficulties encountered in high frequency potential measurement can be avoided by use of an oscillator which measures the potential it generates. The design, construction and calibration of such an oscillator are herein outlined.
Some Uses of the Torque Magnetometer
Authors: Williams H. J.
Published: February 2005

The history of torque measurement as an index of ferromagnetic anisotropy is outlined. A simple magnetometer for torque measurement is described in detail and uses for the instrument are discussed. These include the measurement of anisotropy constants, coercive force, complete magnetization curves for single directions, and rotational hysteresis losses. With auxiliary ballistic measurement residual inductions and demagnetizing factors are obtainable.
An Improved Method for the Determination of Thermal Diffusivities
Authors: Starr Chauncey
Published: February 2005

The dynamic method of determining thermal diffusivities devised by King has been improved. A sinusoidal temperature is impressed on one end of a wire specimen, and the thermal diffusivity is determined from the measured decrement of the temperature wave traveling along the specimen. Elimination or determination of heat losses is unnecessary. Greater precision is possible with this method than with previous methods. The thermal diffusivity of a pure specimen of nickel, measured at 25°C, was 0.15885 cm2/sec., with a probable error of 0.06 percent. The thermal conductivity of nickel corresponding to this determination is 0.618 watts/cm °C.
Half-Cycle Spot-Welder Control
Authors: Gray T. S. , Nottingham W. B.
Published: February 2005

A circuit for controlling a small spot-welder is described which utilizes simple, inexpensive, cold cathode tubes. Variation of the welding heat is accomplished by control of the fraction of a single half-cycle during which current is supplied to the welder transformer. Increased pressure is found to be necessary for satisfactory welding.
Improvements in the Air-Driven Ultracentrifuge for Molecular Sedimentation
Authors: Wyckoff Ralph W. G. , Lagsdin J. B.
Published: February 2005

A description is given of the following improvements in an air-driven ultracentrifuge intended for molecular sedimentation: (1) A driving mechanism equipped (A) with reversing air jets that provide for smooth and rapid stopping and (B) with spring compression screws for adjustment to eliminate vibrations. (2) A head which makes it possible to centrifuge considerable volumes of solution in a field sufficiently great to concentrate and crystallize large protein molecules. (3) The use of a high pressure mercury arc in place of the usual direct-current lamp as light source for both absorption and refractive index measurements. (4) A device for automatically taking the series of photographs needed for determinations of rate of sedimentation.
A Precision Two Crystal X-Ray Spectrometer of Wide Applicability with Worm Wheel Drive; an Improved Precise Method of Equalizing the Spacing of Worm Wheel Teeth
Authors: DuMond Jesse W. M. , Marlow Douglas
Published: February 2005

This article describes the design and construction of a two crystal x-ray spectrometer for the study of radiation of wave-length from (but not including) the vacuum region to about 100 X.U. Versatility coupled with precision of angular measurement is obtained by the use of worm gears, the spacing of whose teeth has been corrected by a relatively cheap but effective lapping method herein described.
A Tube for the Production of Monochromatic and Fluorescent X-Rays
Authors: Pierce W. C. , Olson C. M. , MacMillan D. P.
Published: February 2005

An x-ray tube which may be used for the production of monochromatic rays of high intensity is described. The monochromatic beam is obtained by reflection from a crystal mounted within the tube. By a slight modification the tube may also be used for production of fluorescent x-rays from samples mounted close to the focal spot within the tube.
An Inverted Air-Driven Ultracentrifuge
Authors: Beams J. W. , Linke F. W.
Published: February 2005

An air-driven ultracentrifuge is described in which the air turbine is below rather than above the large rotor or centrifuge. The centrifuge is mounted inside a vacuum tight chamber on a flexible shaft which extends vertically downward, through an oil gland that seals the vacuum chamber, to the turbine below the chamber. The rotating parts are supported upon an air cushion below the turbine. The turbine is driven by air jets. The rotation of the centrifuge is very smooth and the maximum speed is limited only by the strength of the centrifuge.
Thermionic Control of an Ionization Gauge
Authors: Ridenour Louis N. , Lampson C. W.
Published: February 2005

An improved method of controlling the grid current of an ionization gauge is described. The principle employed is applicable to control of current or voltage in a variety of low power circuits.
An Apparatus for the Measurement of the Total Normal Thermal Emissivity of Sheet Materials in the Temperature Range 140 to 500°F
Authors: McDermott Paul F.
Published: February 2005

A description is given of an apparatus for measuring the total normal thermal emissivity of sheet materials up to ⅜ inches in thickness at temperatures from 140 to 500°F without contact or damage to the surfaces viewed. An analysis of possible errors is made which shows the outer limits of absolute values to be within ±1 percent of black-body emission. A table of emissivities as measured are given with values from the literature included for comparison. By minimizing errors due to reflection, the values for poor emitters are found to be somewhat lower than usually reported and are held to be more accurate.
A 200 kv Neutron Source
Authors: Slack C. M. , Ehrke L. F.
Published: February 2005

A tube is described for the utilization of the D — D reaction in the production of neutrons. A capillary arc ion source and a target of heavy ice are employed. The activation in Ag by the neutrons produced with 280 microamperes of unresolved ions at 200 kv was ten times that obtained when a 200 millicurie radon beryllium source was substituted.
A Portable Phototube Unit Using an RCA 954 Tube
Authors: Gabus G. H. , Pool M. L.
Published: February 2005

The problem of the amplification of minute photoelectric currents by means of standard radio apparatus is discussed and a common reason for failure to obtain high sensitivity with ordinary tubes is pointed out. A radio receiving tube is described and its input resistance is raised from 108 to 1013 ohms by means of special use of its grids together with greatly reduced operating voltages. It is shown that this value of input resistance is higher than necessary for ordinary measurements made with the various electrometer type tubes. A comparison curve, showing the region of applicability for three tube types, is included.
An Absolute Method for Measuring the Dielectric Constants of Fluids and Solids at Ultra-High Frequencies
Authors: King Ronold
Published: February 2005

A new parallel wire method has been devised for measuring the dielectric constants of fluids and solids at ultra-high frequencies. A relatively small sample in the form of a thin slab is required. The mathematical relation upon which the experimental determination depends involves only the wave-length at which the measurements are made, the thickness of the sample, and a bridge shift along the parallel wires measured in air. This relation is derived, the experimental technique is outlined, and sample results obtained with water and alcohol are given.
A Method for Sealing β-Magnesia Windows into Steel Spectroscopic Absorption Furnaces and a Needle Valve for Controlling the Evacuation of Such Furnaces
Authors: Brice R. T.
Published: February 2005

A method is described whereby β-magnesia windows may be sealed into heavy steel tubes, thus making them suitable for vacuum furnaces. These seals, utilizing copper or aluminum bands around the edges of the windows, have been made and tested up to 587°C without leaking. A needle valve is designed which permits the opening or closing of an evacuation port in the side of a vacuum furnace at will. This valve operates at the temperature of the furnace and does not introduce a cold spot into the absorption chamber. It has been tested up to 587°C and holds well against pressure differences of one atmosphere. Being made of stainless steel, it is relatively inert and is free from oxidation scale.
A Rochelle Salt Electrometer
Authors: Golay Marcel J. E.
Published: February 2005

Rochelle salt electrometers may be used to advantage where space requirements demand a device of small size. They are useful if they are to operate in a high impedance circuit. They also serve to study conveniently the piezoelectric properties of Rochelle salt.
Construction and Properties of the Manganin Resistance Pressure Gauge
Authors: Adams L. H. , Goranson R. W. , Gibson R. E.
Published: February 2005

It has been shown that the pressure coefficient of a coil of wire depends on the size and construction of the coil as well as upon the composition of the wire. The linearity of the pressure-resistance relation also depends on the size and type of coil. The effect of winding, of heat treating, and of pressure seasoning on the resistance and pressure coefficient of various coils has been determined and measurements have been made on the effect of temperature on the pressure coefficient of manganin. Convenient equations applicable to the ``fixed bridge'' method for measuring small resistance changes are presented.
An Astatic Magnetometer for Measuring Susceptibility
Authors: Johnson E. A. , Steiner W. F.
Published: February 2005

A rugged type of astatic magnetometer has been designed and built for use in the shop and laboratory to measure susceptibility of materials. The sensitivity may be adjusted from 2×10−8 to 1×10−5 electromagnetic c.g.s. unit per scale division, allowing the measurement of volume susceptibility of practically any material.
Use of an Alternating Current Bridge in Laboratory Temperature Control
Authors: Benedict Manson
Published: February 2005

An alternating current bridge and amplifier for continuous temperature control of furnaces and thermostats is described. The circuit is simple and portable and can be made from standard electrical equipment. The power output of the control circuit is doubled for a change of 0.03 percent in resistance of the regulating thermometer. Regulated power up to 500 watts may be obtained. The control circuit has been used to maintain the temperatures of an oil bath and a furnace constant within 0.03°C per hour.
Properties of the Proportional (Geiger-Klemperer) Counter
Authors: Brubaker Gordon , Pollard Ernest
Published: February 2005

A variety of different gases at different pressures have been introduced into a wire form proportional counter and the linearity of response over the entrance studied. It is found that this varies markedly with the nature and pressure of the gas, being very poor for gases which readily form negative ions and improving for almost all gases as the pressure is reduced. An incomplete explanation of the behavior of the counter in terms fo the formation of negative ions is given, which is useful as a qualitative guide. Suitable gases and pressures are recommended for various types of particle counting.
The Focusing of Electrons in an X-Ray Tube
Authors: Beese N. C.
Published: February 2005

A theory is proposed that accounts for the variations in the observed focal spot patterns on the anodes of x-ray tubes caused by changes in the geometry of the cathode structures. The focusing of electrons emitted by a helical filament within a focal cup can be explained qualitatively by elementary electrostatics. Data are presented to show the variations in size and energy distribution within the focal spots when changes are made in the dimensions of the focal cup mouth, throat, filament diameter and the mounting depth of the filament in the trough of the focal cup.
A Curve Tracer for Two, Three or Four Variables
Authors: Awender H. , Tombs D. M.
Published: February 2005

A curve tracer is described which enables the relationship between two, three, or four variables to be observed and recorded. An optical arrangement is made to project an image of an L-shaped aperture onto photographic paper for recording, onto a mat screen for observation, or onto a larger screen or blackboard for demonstration purposes. By means of the surface mirrors attached to two measuring instruments, the image of the aperture may be moved to any point on the screen depending on the deflection of the instruments. By means of the two light shutters attached to two other instruments the lengths of the vertical and horizontal arms of the L aperture are determined by the instrument deflections. Thus the apparatus provides a two-coordinate system (the image of the L-shaped aperture) moving within a second two-coordinate system (the screen). Thus the value of two, three, or four variables can be seen at a glance, and their interrelations watched while one or more of the variables is altered. The scale on any axis may be altered by the adjustment of a continuously wound shunt. Any small variation that may be of special interest may thus be readily magnified. Full scale deflection for each component is obtained over a range from 20 mv to 2000 v or 2 ma to 2 amp. The maximum size of the photographic record is 13×18 cm. The apparatus is not concerned with rapidly varying phenomena, except insofar as these may be registered as the steady deflection of a measuring instrument. The application of the instrument is described in relation to the characteristics of a split-anode magnetron.
A Compensating Circuit for Blocking-Layer Photoelectric Cells
Authors: Brice Brooks A.
Published: February 2005

A compensating circuit comprising two blocking-layer photoelectric cells in a parallel connection with a galvanometer and potentiometer-rheostat is described. Analysis of the circuit shows that a uniform scale attached to the potentiometer-rheostat may be used to indicate transmission (or reflectance) of light by a sample if the resistance of the potentiometer and the series internal resistances of the photoelectric cells are small in comparison with the parallel internal resistances of the photoelectric cells. The performance of the circuit under different conditions was tested by means of wire screens of known transmission. With moderate illumination on the photoelectric cells and using a 50 ohm potentiometer-rheostat carrying a scale graduated from 0 to 100, errors in indicating transmission are believed to be not greater than ±0.1 on this scale.
The Thirty Kilowatt Continuous Input X-Ray Equipment and High Constant Voltage Generating Plant of the Watters Memorial Research Laboratory at the California Institute of Technology
Authors: DuMond Jesse W. M. , Youtz J. Paul
Published: February 2005

This report describes in detail with photographs and cross-sectional views an x-ray tube with a gyrating water-cooled target which the authors have operated continuously for periods of hours at 287,000 volts and 105 milliamperes. The theoretical predictions of DuMond, Watson and Hicks as to the ratio of safe load in moving and fixed targets seems to be roughly fulfilled by these results. The computed power output in the form of x-rays alone is some 3/4 kilowatt. The report further describes in detail the power supply equipment consisting of a synchronous motor driven 40 kw motor generator set giving 150 cycle current both half-waves of which, after transformation to high voltage, are rectified by two thermionic valves (filament emission 2 amperes maximum) of our own design and construction here fully described. The powerful electrical filter system to reduce the ripple to a low value and some technical problems arising from the large power rating of the equipment as well as the facilities now almost completed for stabilizing and measuring precisely the high voltage supplied to the x-ray tube are discussed. At the outset a brief indication of the program of research work projected for this set is given.
A Torsion Manometer for the Measurement of the Force of a Molecular Ray
Authors: Copley M. J. , Deitz Victor
Published: February 2005

The construction and operation of a torsion manometer for the measurement of the force exerted by a molecular ray is described. The manometer was used to measure the vapor pressures of KCl and CsI crystals in the range of temperature 800–950°K. The results obtained suggest that it is possible to develop this method to a degree where it will yield data at least as accurate as that obtained by other methods. Some applications of the torsion manometer are discussed.
The Design of Powerful Electromagnets Part III. The Use of Iron
Authors: Bitter F.
Published: February 2005

In a previous paper having the above title a numerical error was made in the calculations. This is corrected, and experimental results on a small iron magnet are described.
Time Delay Circuit for Operating Wilson Cloud Chambers
Authors: Jones Creighton C.
Published: February 2005

A circuit has been developed in which grid glow tubes with time delay inputs perform all the switching operations necessary to operate a Wilson cloud chamber and its accessory mechanisms. The cycle of operations can be initiated either at regular intervals (by a motor and reduction gear) or by coincidences in Geiger counters placed above and below the chamber. The change over from one mode of operation to the other is very simple.
A Self-Fractionating Oil Diffusion Pump
Authors: Lockenvitz Arthur E.
Published: February 2005

A six-stage oil diffusion pump is described, using ordinary lubricating oil which is fractionally distilled in the pump so that a vacuum of 10−6 mm can be obtained without the use of vapor traps.
A Bridge Balance Indicator
Authors: Garman R. L.
Published: February 2005

An electronic device for the detection of bridge balance is described herein. It employs no meters but instead uses a visual indicator tube. The circuit is so arranged that the sector moves only when the bridge is near balance; thus high sensitivity is attained with the small scale available with these tubes. A second tube is used to establish approximate balance and provision is also made for neutralizing small residual signals. In this way minimum points may be determined with a high order of precision.
Machined Metal Stuffing Box Seals Adapted to High Vacuum Technique
Authors: Garner L. P.
Published: February 2005

Vacuum seals machined from metals and adapted to vacuum technique are described and shown in several forms suitable for joining metal and glass components. Precautions in construction and use are given. Dimensioned working drawings for several sizes of one type are shown.
Wheatstone Bridge and Electrolytic Resistor for Impedance Measurements Over a Wide Frequency Range
Authors: Cole Kenneth S. , Curtis Howard J.
Published: February 2005

A versatile Wheatstone bridge is described for alternating current impedance measurements at frequencies from 30 to 10,000,000 cycles. Variable electrolytic resistors have proven very satisfactory both for balancing the bridge and as secondary standards of resistance. A selector switch in each working arm permits any one of nine different combinations of impedances to be connected in the arm so that it is possible to make either direct or substitution measurements against either wire wound or electrolytic resistors. Substitution measurements are made with an electrolytic resistor over the frequency range in 20 minutes, with an impedance accuracy of 0.2 percent. The equipment was designed and has been used primarily for impedance measurements of biological materials.
A Source of Variable Rectangular Pulses
Authors: Peugnet Hubert B.
Published: February 2005

There is described a device for the production of rectangular current pulses of variable strength and duration, which does not require the use of mechanical timing accessories.
Transmission of Radiant Energy Through the Atmosphere
Authors: Hayes Hammond Vinton
Published: February 2005

This paper reports progress in the development of apparatus for the transmission of signals in times of obscured vision. Descriptions of the results of tests made almost daily from November 12, 1936 to May 20, 1937 in the transmission of signals over distances of about 480 meters and about 2400 meters using the Hayes Radiometer as the receivers and sources of radiant energy of varied power and nature are given. There was not a day in the period covered where good signals were not received from a 25-watt source over the shorter range nor any day when good signals were not received over the longer range when a source actuated by an input of about 650 watts was used. There were but two days when the 25-watt source failed to transmit clear signals over the longer range of about 2400 meters. On these days the air was filled with heavy wet snow.
Simulated rainwater effects on anion exchange capacity and nitrate retention in Ferrosols
Authors: Donn M. J. , Menzies N. W.
Published: February 2005

Nitrate (NO3) accumulations (up to 1880 kg NO3-N/ha for a 12-m profile) in the soils of the Johnstone River catchment (JRC) may pose a serious environmental threat to the Great Barrier Reef lagoon if the NO3 were released. The leaching of artificial rainwater through repacked soil columns was investigated to determine the effect of low NO3/low ionic strength inputs on the NO3 chemistry of the JRC profiles. Repacked soil columns were used to simulate the 11.5-m profiles, and the soil solution anion and cation concentrations were monitored at 10 points throughout the soil column. As the rainwater was applied, NO3 leached down the profile, with substantial quantities exiting the columns. Anion exchange was discounted as the major mechanism of NO3 release due to the substantial net loss of anions from the system (up to 2740 kg NO3-N/ha over the experimental period). As the soils were dominated by variable charge minerals, the effect of changing pH and ionic strength on the surface charge density was investigated in relation to the release of NO3 from the exchange. It was concluded that the equilibration of the soil solution with the low ionic strength rainwater solution resulted in a lessening of both the positive and negative surface charge. Nitrate was released into the soil solution and subsequently leached due to the lessening of the positive surface charge. Loss of NO3 from the soil profile was slow, with equivalent field release times estimated to be tens of years. Although annual release rates were high in absolute terms (up to 175 kg NO3-N/ha.year), they are only slightly greater than the current loss rates from fertilised sugarcane production (up to 50 kg NO3-N/ha.year). In addition to this, the large-scale release of NO3 from the accumulations will only occur until a new equilibrium is established with the input rainwater solution.
Carbon storage in the soils and vegetation of contrasting land uses in northern New South Wales, Australia
Authors: Young Rick , Wilson Brian R , McLeod Malem , Alston Clair
Published: February 2005

The organic carbon stock in biomass and soil profiles sampled from nearby paddocks with different land-use histories was estimated at 7 sites in the upper Liverpool Plains catchment and the Manilla district of north-western New South Wales, Australia. The distribution of soil carbon concentrations over a depth of 2 m was significantly affected by site and land use. Continuous cultivation and cropping over ≥20 years significantly depleted carbon concentrations compared with grassy woodlands in the surface 0.20 m at all sites and to a depth of 0.60 m at 3 sites. Depth of sampling (0–0.20 v. 0–1.0 m) significantly affected the differences between land uses at most sites regarding estimates of the stock of soil carbon. These results show that differences in soil carbon concentrations and stock size do not remain constant with depth between contrasting land uses. However, comparisons between land uses of the total amount of carbon stored were dominated by the number of trees per ha and the size of the trees in grassy woodlands. The implications of these results for carbon accounting are discussed.
Dopamine supersensitivity correlates with D2Highstates, implying many paths to psychosis
Authors: Seeman Philip , Weinshenker David , Quirion Remi , Srivastava Lalit K. , Bhardwaj Sanjeev K. , Grandy David K. , Premont Richard T. , Sotnikova Tatyana D. , Boksa Patricia , El-Ghundi Mufida , O'Dowd Brian F. , George Susan R. , Perreault Melissa L. , Männistö Pekka T. , Robinson Siobhan , Palmiter Richard D. , Tallerico Teresa
Published: February 2005

Dopamine supersensitivity occurs in schizophrenia and other psychoses, and after hippocampal lesions, antipsychotics, ethanol, amphetamine, phencyclidine, gene knockouts ofDbh(dopamine β-hydroxylase),Drd4receptors,Gprk6(G protein-coupled receptor kinase 6),Comt(catechol-O-methyltransferase), orTh-/-,DbhTh/+(tyrosine hydroxylase), and in rats born by Cesarean-section. The functional state of D2, or the high-affinity state for dopamine (D2High), was measured in these supersensitive animal brain striata. Increased levels and higher proportions (40-900%) for D2Highwere found in all these tissues. If many types of brain impairment cause dopamine behavioral supersensitivity and a common increase in D2Highstates, it suggests that there are many pathways to psychosis, any one of which can be disrupted.
High Intensity Neutron Spin Flip Chopper
Authors: Ebisawa T. , Soyama K. , Yamazaki D. , Tasaki S. , Sakai K. , Oku T. , Maruyama R. , Hino M.
Published: February 2005

We have proposed multi-stage spin flip chopper system to realize very high S/N ratio. Very high S/N ratios of about 3000 and 105 have been demonstrated for double and triple spin flip chopper systems, respectively. We here describe a double neutron spin flip chopper system applicable to pulsed source using polarizing bent guide tubes instead of simple magenetic mirrors, in order to obtain a high intensity and high S/N ratio. Simulation results show that it will realize spin flip chopper of high neutron intensity and S/N ratios.
European explorers, entrepreneurial selection and environmental thresholds
Authors: CLYDESDALE GREG
Published: February 2005

This article examines the activities of two early European explorers, Christopher Columbus and Henry the Navigator, in light of modern theories on entrepreneurship. These were Schumpeter‐type entrepreneurs who revolutionised the world of trade and commerce. Their eventual success was the result of a number of factors including technology, access to capital, access to information, their skill‐base, social/motivational factors and luck. All of these factors, in turn, were determined by their environment. Their reliance on knowledge and technology show these entrepreneurs as being one stage in a technological trajectory and growth of knowledge. This stage represented a major threshold in which a window of opportunity was opened. This illustrates a process of environmental selection whereby entrepreneurial success is determined by changes in the environment.
‘Genius’, ‘faction’ and rescuing intellectual property rights
Authors: KINGSTON WILLIAM
Published: February 2005

Intellectual property rights have been driven relentlessly towards a unitary system for the entire world, originally through passive copying of flawed United States arrangements, but more recently as a result of determined lobbying by American interests. But diversity and competition have the same beneficial potential for institutions themselves as they have for the economic development they can foster or hinder. A financial dimension in measuring grants, protecting innovation directly, compulsory technical arbitration of disputes, and some positive discrimination in favour of smaller firms could contribute to moving the balance back towards the diversity in rights that other countries need.
A taxonomy of public research bodies: A systemic approach1
Authors: COCCIA MARIO
Published: February 2005

Nowadays the governments of industrialised countries, in the presence of reduced public resources, have to assign clear objectives to public research laboratories to increase the competitiveness of firms. The purpose of this article is to analyse the public research bodies of the National Research Council of Italy in order to pinpoint the main typologies operating in the national system of innovation (NSI). This research shows four main types of research institutes as drivers of NSI. The results can supply useful information to policy makers on the behaviour of these structures and on their strengths and weaknesses.
Technology‐related factors contributing to labour intensification of surgical production
Authors: JOHNSTONE P. LYNNE
Published: February 2005

The late 1980s heralded the start of what is widely acknowledged as a period of enormous technological change in surgery, particularly, but not limited to, minimum access surgery either displacing conventional open surgical techniques or providing new opportunities for surgical treatments. This article discusses the main technology‐related factors contributing to the significant, but unanticipated, labour intensification of surgical production within operating departments—reasons that are not consistent with the pervasive theme of the techno‐economic literature that generally equates ‘new technology’ with automation, labour displacement, work simplification, and the economic benefits accruing to an organisation.
Recent Progress of the Project of the Chinese Spallation Neutron Source
Authors: Zhang J. , Yan Q.W. , Zhang C. , Zhang P.L. , Fu S.N. , Wang F.W. , Zhang Z. , Fang S.X.
Published: February 2005

We report on the recent progress of the project of the Chinese Spallation Neutron Source. The preliminary conceptual designs of the accelerator complex, the target system and the neutron scattering instruments are included.
Harvesting Precious Metals and Removing Contaminants from Natural Waters—Can Neutrons Benefit Industrial Researchers in Japan?
Authors: Loong C.-K. , Koyanaka H.
Published: February 2005

Understanding material properties at a fundamental level is important to the development of the full potential of substances and the fruition of eventual industrial and commercial applications. The techniques of neutron-scattering provide unique capabilities in characterization of materials at nanometer scale thereby benefiting industrial research. We focus on a recent study of lithium extraction and arsenic removal from natural waters using nanostructured manganese-oxide based adsorbents. Neutron diffraction and spectroscopy, when combining with other characterization techniques and theoretical modeling, contributed to the understanding of the relation between adsorption behavior and material properties.
Pressure Response on Hydrogen Bonds in Potassium Hydrogen Carbonate and Sodium Hydrogen Carbonate
Authors: Kagi H. , Nagai T. , Komatsu K. , Okada T. , Wada C. , Loveday J.S. , Parise J.B.
Published: February 2005

Pressure responses of hydrogen bonding interactions were compared between potassium hydrogen carbonate (KHCO3) and sodium hydrogen carbonate (NaHCO3). KHCO3 undergoes a pressure-induced structural change at 2.8 GPa and room temperature whereas no phase transition has been found so far for NaHCO3 up to 11 GPa. KHCO3 exhibits a substantial decrease in the O—H···O angle with increasing pressure. This change could be a trigger for the phase transition at 2.8 GPa. By contrast, no significant change in O—H···O angle was observed for NaHCO3 up to 7 GPa. Based on the observations using neutron diffraction, X-ray diffraction and vibrational spectroscopy at high pressure, a possible mechanism for the phase transition of KHCO3 is suggested. In addition, the phase boundary of KHCO3 caused by the pressure-induced transition was determined using in situ Raman spectroscopy at high pressure.
Neutron Imaging—Present Status and Options with TOF Methods—TOF Neutron Imaging
Authors: Lehmann Eberhard H. , Vontobel P. , Frei G.
Published: February 2005

This article describes the status of neutron imaging with the focus on the detection systems in use, mainly based on a digital approach. When intense pulsed will be available in the near future, neutron imaging can take profit too by applying energy selective and triggered “flash” methods for dedicated investigations. Therefore, the layout, specifications and options should be discussed now in order to have the right beam line available at one or some of the pulsed sources.
New Generation of Neutron Decay Experiments
Authors: Gudkov Vladimir
Published: February 2005

New generation of neutron decay experiments, which can be done with high accuracy at new Spallation Neutron Sources, are very important for solution of current problems of fundamental physics and for tests of the Standard Model. The open problems of theory related to these experiments and possible approaches to their solutions are discussed.
Neutron Scattering Study of the Anisotropic Spin Fluctuation in Sr2RuO4
Authors: Kawano-Furukawa H. , Urata M. , Nagata T. , Yoshizawa H. , Kadowaki H. , Dai P.
Published: February 2005

In this paper, we present the results of our unpolarized inelastic neutron scattering experiments on the spin-triplet superconductor Sr2RuO4. Our measurements showed that incommensurate spin susceptibilities at q0 = (0.3 0.3 0) exhibit c-axis anisotropy. This discovery supports the notion that magnetic anisotropy may induce p-wave superconductivity in this material.
Single Crystal Pulsed Neutron Diffractometer for Biologically Important Materials Crystallography No.1 (BIX-P1) at Material and Life Science Facility in J-PARC
Authors: Tanaka I. , Ozeki T. , Ohhara T. , Kurihara K. , Niimura N.
Published: February 2005

Japan proton accelerator research complex (J-PARC) with the power of 1 MW have been constructing since 2001 in JAERI, Japan. And the first beam will come by 2007. As one important day-one neutron instruments at Material and Life Science Facility in J-PARC, a single crystal diffractometer No.1 for structural analysis of biological macromolecules and organic compounds with unit cell dimensions less than about 135 Å (BIX-P1) has been proposed, considering the international competition in biological science and the expansion of the application to the industrial fields. It is expected to gain efficiency more than 50 times larger than neutron biological diffractometers BIX-3 and BIX-4 installed at JRR-3 reactor also in JAERI. In this paper, evaluation of moderator, items of necessary R & D and the current specification of BIX-P1 are shown.
Powder Diffractometers of J-PARC
Authors: Ishigaki T. , Kamiyama T. , Oikawa K.
Published: February 2005

In the J-PARC project, we are proposing two powder diffractometers. This article describes these powder diffractometers: a versatile diffractometer with resolution of Δd/d ≈ 0.1% for materials science and a high- resolution diffractometer with Δd/d ≈ 0.03% for precise analysis. Each of them looks at the other side of an off- centered decoupled hydrogen poisoned moderator. Another type of high intensity powder diffractometer is also proposed separately as a total scattering instrument.
Two-dimensional Solids Formed at Interfaces
Authors: Inaba A. , Sakisato N. , Bickerstaffe A.K. , Clarke S.M.
Published: February 2005

There is a continuing interest in “2D solids” which appear at various interfaces for their novel structure and dynamics. Many simple molecules are adsorbed on solid surfaces, such as graphite, to form 2D layers that are solid at low temperatures. Interestingly, similar solid monolayers are formed at the interface between bulk liquid adsorbates and graphite. In this work, we report a 2D-like ice structure which appears in the initial stage of crystallisation of aqueous solutions from the undercooled state. We present results obtained by neutron scattering to demonstrate the formation of this novel structure and its temperature evolution.
Observation of Mesoscale Structure of 1-propanol Aqueous Solution and its Visualization
Authors: Misawa M. , Dairoku I. , Honma A. , Yamada Y. , Sato T. , Maruyama K. , Mori K. , Suzuki S. , Otomo T.
Published: February 2005

Absolute intensity of small angle neutron scattering (SANS) has been measured for 1-propanol aqueous solution. Fractal dimension evaluated from the observed intensity depends on 1-propanol content in a peculiar way. Mesoscale structure of the solution has been visualized by means of large-scale reverse Monte Carlo (RMC) technique. It is suggested that most molecules are located on surface of clusters and cluster-size distribution obeys a simple power law.
Remote-sensing, Non-destructive, and Computed-tomography-assisted Thermometry by Neutron Resonance Absorption Spectroscopy
Authors: Kamiyama T. , Noda H. , Ito J. , Iwasa H. , Kiyanagi Y. , Ikeda S.
Published: February 2005

We applied the method of neutron resonance absorption spectroscopy to thermometric measurements of a bulk object. Through an analysis of the resonance absorption spectrum of imbedded neutron-absorbing nuclides, the “effective temperature”, which coincides with the actual local temperature near and above room temperature, can be determined. If a thermal gradient exists, computed tomography techniques could be used in conjunction with the analysis for a reconstruction of the temperature distribution over a planar cross-sectional area. We find that the experimental data agree with the temperature profile calculated from the heat conduction equations. The measurements were carried out using the neutron resonance absorption spectrometer DOG of KENS, Japan. The overall results demonstrated the feasibility of this method for industrial applications where remote-sensing and non-destructive temperature mapping of bulk objects is necessary.
Structural Studies of Hydrated Tricalcium Silicate by Neutron Powder Diffraction
Authors: Mori K. , Yatsuyanagi K. , Oishi K. , Fukunaga T. , Kamiyama T. , Ishigaki T. , Hoshikawa A. , Harjo S. , Iwase K. , Itoh K. , Kawai M.
Published: February 2005

Structure refinements have been carried out on the pure tricalcium silicate (C3S) and the hydrated C3S with the D2O–C3S mass ratio, which is 0.5, using neutron powder diffraction (NPD). The multi-phase Rietveld analysis of the hydrated C3S revealed the coexistence with the Ca(OD)2 (trigonal phase) and the unhydrated C3S (triclinic one). The Ca(OD)2 phase was hardly observed on the NPD patterns in the first ∼6 h of hydration, while the several Bragg reflections of Ca(OD)2 appeared drastically from ∼6 to ∼24 h, and then the hydration reaction rate was gradually suppressed. We could apply the Avrami-model to the initial hydration reaction process of C3S.
Development of Neutron Polarizer–Analyzer System for T-invariance Experiment
Authors: Skoy V.R. , Masuda Y. , Muto S. , Ino T. , Kim G.N. , Jones G.
Published: February 2005

A neutron polarizer–analyzer system based on polarized 3He is being developed at KEK Pulsed Neutron Source for an experiment on time reversal invariance in the nuclear reaction at J-PARC.
Overview of the J-PARC Project
Authors: Nagamiya Shoji
Published: February 2005

From Japanese fiscal year JFY01, which started on April 1, 2001, a new accelerator project to provide high-intensity proton beams proceeded into its construction phase. This project, which is now called the Japan Proton Accelerator Research Complex (J-PARC) project, is in progress under a cooperation of two institutions, High Energy Accelerator Research Organization (KEK) and Japan Atomic Energy Research Institution (JAERI). We set a goal to achieve 1 MW proton beams at 3 GeV and 0.75 MW beams at 50 GeV. The construction period is seven years, with anticipated first beams in the spring of 2008. In this article, I will describe the project itself and the present status of the project.
Neutron Reactions in Astrophysics: The Role of New Facilities and Improved Laboratory Approaches
Authors: Käppeler F.
Published: February 2005

The abundance of elements between Fe and the actinides have essentially all been produced by neutron reactions, either by the slow neutron capture process during helium burning in red giant stars (s process) or by explosive nucleosynthesis, e.g. in supernovae (r and p process). Laboratory studies have so far concentrated on the s process, which operates in or near the valley of β-stability. Under these conditions laboratory results are of direct impact for the interpretation of the observed abundance patterns and their role as crucial tests for stellar evolution models. The high flux at spallation neutron sources allows one to investigate numerous difficult and hitherto inaccessible cases, including the cross sections of important radioactive nuclei.
Aspects of Neutron Spin-echo Spectrometer Operation on a Pulsed Source
Authors: Monkenbusch M. , Ohl M. , Richter D. , Pappas C. , Zsigmond G. , Lieutenant K. , Mezei F.
Published: February 2005

Measures to optimally operate a neutron spin-echo (NSE) spectrometer at a pulsed source are discussed. Gain factors and resolution functions are addressed.
Protein Dynamics at JSNS and SNS: Prospects and Challenges
Authors: Middendorf H.D.
Published: February 2005

The third-generation neutron facilities under construction at Tokai (JSNS) and at Oak Ridge (SNS) will provide opportunities for strengthening and expanding research on biomolecular dynamics. Following an outline of current trends in biomolecular applications of quasielastic (QENS) and inelastic (INS) neutron scattering, this paper discusses likely directions of future work on proteins and identifies challenging problem areas.
On the Way to Experimental Test of the Time Reversal Invariance in the Nuclear Reactions
Authors: Skoy V.R. , Masuda Y. , Muto S. , Ino T. , Kim G.N.
Published: February 2005

T violation can be related with the CP-violation through Luders–Pauli’s CPT theorem, which is related with a local Lorentz invariant field theory. The CP violation was discovered experimentally in the K0-meson decays about 35 years ago. The T violating interaction related with the CP violation violates parity as well. However, an extension of the theory beyond the locality of the interactions might violate the CPT theorem. The result of CPLEAR experiment [Angelopolos A. et al., (1998), “First direct observation of time-reversal non-invariance in the neutral-kaon system”, Phys. Lett. B 444 43], which has given direct evidence of T violation in the elementary-particle phenomena, could be considered under assumption of the CPT invariance.
Quasi-elastic Neutron Scattering Measurements of Liquid Germanium
Authors: Kato Y. , Kawakita Y. , Shibata K. , Takeda S. , Pilgrim W.-C.
Published: February 2005

Quasi-elastic neutron scattering measurements of liquid germanium were carried out at 1000 and 1500°C, using the inverted geometry inelastic neutron spectrometer, LAM-40. The dynamic structure factor, S(Q,E), is obtained over a wide momentum transfer region from 0.6 to 5.1 Å−1.
Neutron Diffraction Study on Microinhomogeneities in Ethanol–Water Mixtures
Authors: Yamaguchi T. , Takamuku T. , Soper A.K.
Published: February 2005

Neutron diffraction with isotopic substitution measurements have been made at room temperature on seven isotopically substituted ethanol–water mixtures at 0.1, 0.2 and 0.4 ethanol mole fractions, respectively, from which nine composite partial structure factors, HH, HX and XX (X denotes the weighted sum of non-substituted atoms) were derived on water–water, water–ethanol and ethanol–ethanol interactions for each of the solutions. The partial structure factors were then subjected to an empirical potential structure refinement simulation to derive all site–site pair correlation functions. An origin of the so-called microinhomogeneities in ethanol–water mixtures has been established at the molecular level on the basis of the pair correlation functions, which probably underlines the mechanism of anomalous behaviors in physico-chemical quantities and alcohol-induced denaturation of proteins in ethanol–water mixtures.
The Design of the Neutron Total Scattering Spectrometer for Hydrogenous Materials at J-PARC-JSNS
Authors: Suzuya Kentaro , Kameda Yasuo , Otomo Toshiya , Yoshida Koji , Itoh Keiji , Fukunaga Toshiharu , Misawa Masakatsu
Published: February 2005

The design, performance, philosophy, lessons learned and advantages of the neutron total scattering spectrometer for hydrogenous materials, FAST, under consideration for the J-PARC-JSNS, are described. In particular, novel instrumentation concept such as the small fractional scattered neutron flight path, γ = L2/(L1 + L2), where L1 is the incident flight path, moderator to sample, L2 is the scattered neutron flight path from sample to detector, is presented and their expected performance at the JSNS is considered.
A Proposal of TOF-type Double-crystal Diffractometer at JSNS
Authors: Aizawa Kazuya
Published: February 2005

We propose a TOF-type double-crystal ultra-small-angle neutron scattering (USANS) instrument in JSNS. The fundamental arrangement of the TOF-type USANS instrument is the same as a reactor-type USANS instrument. The feature of this instrument is the simultaneous use of harmonics, λ/n (λ is the neutron wavelength, n = 1, 2, 3...). As a result, the covered q-range (q = (4π sin (φ/2))/λ where φ is the scattering angle) is extended towards both lower and higher qs than that of a reactor USANS instrument. In addition, an effective intensity gain is achieved by harmonics multiplication. We calculated the performance of the TOF-type USANS instrument on the coupled liquid hydrogen moderator in JSNS.
Neutron Spin Echo Spectrometers for J-PARC with Resonance Spin Flippers
Authors: Tasaki Seiji , Kawabata Yuji , Hino Masahiro , Maruyama Ryuji , Ebisawa Toru
Published: February 2005

Neutron spin echo (NSE) methods with resonance spin flippers have been developed for 10 years. There are two types of spin echo methods using resonance spin flipper: Neutron resonance spin echo (NRSE) and Mieze. For spallation neutron source like J-PARC, provided that high-frequency neutron spin flippers and appropriate calibration for field integral are realized, NRSE is more suitable than conventional spin echo method since, (1) NRSE can be small and hence it is possible to install two or more spectrometers in one beam line, (2) magnetic shielding over precession region, which is expected to be necessary under huge iron shielding around the sputter source, is possible. The authors suggest a set of NRSE spectrometers and Mieze spectromter sharing one beam line, in which neutrons are separated according to their wavelength range. This system will cover very wide range of Fourier time and will open new applications to NSE method.
High-energy-resolution Option for the Inverted-geometry Time-of-flight Spectrometer DYANA
Authors: Sato Taku J. , Shibata Kaoru
Published: February 2005

DYANA is an inverted-geometry time-of-flight (TOF) spectrometer proposed for the Japan Proton Accelerator Research Complex (J-PARC) project. Here, we show that by introducing pulse-shaping disk choppers and Si 111 analyzer, a DYANA-type short-incident-flight-path spectrometer can attain a very high energy resolution of 2 µeV, with an acceptable neutron flux at the sample position.