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The analytical solution of the bending problem for a clamped rectangular plate with a variable in-plane stiffness is found by using the method of superposition. The flexural rigidity of the plate varies across its width according to an exponential function. First, the analytical solution for a simply supported rectangular plate with a variable in-plane stiffness is obtained, and then the bending problem for the plate clamped at its four edges is solved analytically by the superposition of one simply supported plate under the transverse load and two simply supported plates under pure bending. The influence of the variable in-plane stiffness, aspect ratio, and different boundary conditions on the deflection and bending moment is studied by numerical examples. The analytical solution presented here may be helpful for the design of rectangular plates with a variable in-plane stiffness.

A proper cryogenic environment is essential for the operation of superconducting devices. A test area for the superconducting radio-frequency modules (SRF) has been established in the RF laboratory at National Synchrotron Radiation Research Center in Taiwan; these modules require much liquid helium during conditioning and performance tests; a cooling capacity of 120 W is expected for the acceptance test of the SRF module. The cryogenic environment of the test area is completed on transferring the liquid helium over a remarkable length of 205 m from the two cryogenic plants at Taiwan Light Source, with a valve box located at each end to control and to measure the cryogenic flow. Flexible cryogenic transfer lines of concentric four-tube type are chosen for both the supply of liquid helium and the return of cold helium gas. Functional examination of this long transfer system was first achieved with a 500-L Dewar in the radio-frequency laboratory; an SRF module was then installed in the test area for practical operation. The primary concern about the cryogenic transfer system is the heat loss; a measurement technique based on the principle of thermodynamics is developed and proposed herein. With the available sensors inside the valve boxes and the heaters inside the 500-L Dewar and the test SRF module, this technique has proved promissing from the measured results.

Background Establishing a stand-alone cryogenic test stand is of vital importance to ensure the highly reliable and available operation of superconducting radio-frequency module in a synchrotron light source. Operating a cryogenic test stand relies strongly on a capability to deliver two-phase helium along long cryogenic transfer lines. A newly constructed cryogenic test stand with flexible cryogenic transfer lines of length 220 m at National Synchrotron Radiation Research Center is required to support a superconducting radio-frequency module operated at 126.0 kPa with a 40-W dynamic load for a long-term reliability test over weeks. It is designed based on a simple analytical approach with the introduction of a so-called tolerance factor that serves to estimate the pressure drops in transferring a two-phase helium flow with a substantial transfer cryogenic heat load. Tolerance factor 1.5 is adopted based on safety factor 1.5 commonly applied in cryogenic designs to estimate the total mass flow rate of liquid helium demanded. A maximum 60-W dynamic load is verified with experiment measured with heater power 60 W instead after the cryogenic test stand has been installed. Results Aligning the modeled cryogenic accumulated static heat load with the results measured in situ, actual tolerance factor 1.287 is obtained. The feasibility and validity of our simple analytical approach with actual tolerance factor 1.287 have been scrutinized by using five test cases with varied operating conditions. Calculated results show the discrepancies of the pressure drops between the estimated and measured values for both liquid helium and cold gaseous helium transfer lines have an underestimate 0.11 kPa and an overestimate 0.09 kPa, respectively. A discrepancy is foreseen, but remains acceptable for engineering applications from a practical point of view. Conclusions The simple analytical approach with the introduction of a tolerance factor can provide not only insight into optimizing the choice of each lossy cryogenic piping element of the transfer lines in the design phase but also firm guidance for upgrading the present cryogenic transfer lines for its subsequent application.

A superconducting radio-frequency (SRF) module is commonly used for a high-energy accelerator; its purpose is to provide energy to the particle beam. Because of the low power dissipation and smaller impedance of a higher-order mode for this module, it can provide more power to the particle beam with better stability through decreasing the couple bunch instability. A RF coupler is necessary to transfer the high power from a RF generator to the cavity. A coupler of coaxial type is a common choice. With high-power operation, it might suffer from multipacting, which is a resonance phenomenon due to re-emission of secondary electrons. Applying a bias voltage between inner and outer conductors of the coaxial coupler might increase or decrease the strength of the multipacting effect. We studied the effect of a bias voltage on multipacting using numerical simulation to track the motion of the electrons. The simulation results and an application for SRF operation with a large beam current are presented in this paper.

(BrXP-50), was conducted. Morphological analyses and mechanical tests were combined to evaluate the toughening mechanisms of modified PA-6 and the fracture mechanism of unmodified PA-6. We conclude that the fracture mechanism of unmodified PA-6 in the impact test is crazing-cracking under the dilatational stress created by the plastic constraint, while that of the BrXP-50 elastomer modified PA-6 is plastic tearing limited by the ultimate tensile strain. Cavitation of BrXP-50 elastomer particles occurred in the impact test, and is proposed as a controlling step in toughening: it relieves the plastic constraint so that the cracking process is postponed and additional plastic deformation can occur, leading to higher impact toughness.

We have employed synchrotron radiation photoemission to investigate the electronic structure of tris(8-hydroxyquinolato) aluminum $({\mathrm{Alq}}_{3})$ at room temperature as well as at elevated temperatures. The dependence of the molecular state cross sections on the photon energy is demonstrated. Three chemical environments of carbon are resolved, accompanied with at least two shake-up satellite structures. Small loss structures are detected in other N $1s$, O $1s$, and Al $2p$ core-level spectra, but with various magnitudes. Annealing produces charge redistribution of the molecular states within ${\mathrm{Alq}}_{3}$ itself. ${\mathrm{Alq}}_{3}$ is stable at high temperature.

Synchrotron radiation photoemission was used to investigate the electronic structure of magnesium deposited on tris(8-hydroxyquinolato) aluminum $(\mathrm{Al}{q}_{3})$ with the film thickness from one molecular layer to a thick solid. In a monolayer-thick $\mathrm{Al}{q}_{3}$ on the $\mathrm{Si}(001)\text{\ensuremath{-}}2\ifmmode\times\else\texttimes\fi{}1$ surface, the organic molecules accept from the charge at the surface dimers. However, as Mg is deposited on top of this thin $\mathrm{Al}{q}_{3}$ film, the surface dimers underneath the film start to show reacted magnesium silicide, indicating clearly a prompt diffusion of Mg through $\mathrm{Al}{q}_{3}$. In regard to the $\mathrm{Al}{q}_{3}$ solid, the highest occupied molecular orbital of $\mathrm{Al}{q}_{3}$ shifts monotonically towards high binding energy, and the lowest unoccupied molecular orbital remains fixed in energy with increasing Mg concentration. The N $1s$ core appears an Mg-induced charge-transfer component with a binding energy lower than the original component. This new component grows gradually in intensity with increasing concentration of the dopant. Its energy separation from the original component is $\ensuremath{-}1.51\phantom{\rule{0.3em}{0ex}}\mathrm{eV}$ at small exposure, but widened up to $\ensuremath{-}1.85\phantom{\rule{0.3em}{0ex}}\mathrm{eV}$ at large coverages. Moreover, Mg also affects the O $1s$ core as manifested by a components lying at $+1.09\phantom{\rule{0.3em}{0ex}}\mathrm{eV}$ higher binding energy than the original component. The Mg $2p$ core-level spectra, although rather broad, exhibit a shift towards lower binding energy with increasing Mg vapor. All these experimental evidences suggest that magnesium organometallic complex residing in the surface exhibits an electronic structure differently from the bulk. We propose that Mg in the surface $\mathrm{Al}{q}_{3}$ molecules forms actually clusters. It attaches to a pyridyl ring, affecting not only the nitrogen atom at that ring, but the oxygen atom in the adjacent phenoxide ring. The depleted charge in the affected oxygen flows then about its adherent ligand and resides on the pyridyl ring at that ligand, resulting in a high $\mathrm{Al}{q}_{3}$ anion state.

Rheological behavior of dispersed two-phase polymer melts has been investigated by means of a capillary rheometer. The two-phase systems chosen for study were blends of two polymers: high-density polyethylene and polystyrene, which are incompatible in the molten state. In order to investigate the state of dispersion, photographs were taken of the microstructure of extrudate samples, showing that the polystyrene forms long fibers or droplets as a discrete phase dispersed in the polyethylene which forms a continuous phase. Measurements were made of the axial pressure distributions of the two-phase molten polymers flowing through circular tubes, which permit one, according to the theory advanced by Han, to determine viscous and elastic properties of the melts. Also measured was melt die swell ratio. It has been found from the two independent experimental techniques that there exist a maximum and/or minimum elastic property at a certain blending ratio, and that the elastic property decreases first with L/D ratio of a capillary and then levels off.

Measurements were taken of both viscous and elastic properties of polystyrene melts, using a capillary rheometer recently constructed byHan. The viscous property is determined from the slope of the axial pressure distribution, and the elastic property is determined from the exit pressure, which is obtained at the tube exit when the straight line portion of the axial pressure profile is extrapolated to the exit of the tube. Previous studies ofHan demonstrated that the exit pressure thus obtained can be correlated with die swell ratios, and that the exit pressure is equal to the normal stress difference for polymer melts in fully developed viscometric flow. The present study of polystyrene melts corroborates all previous correlations obtained with high density polyethylene and polypropylene melts as regard the exit pressure measurements. A salient feature of the method employed here is that it requires only a single capillary, long enough to assure that flow is fully developed.

Recently determined Fourier coefficient data for cold‐worked β‐AlNi diffraction peaks were analyzed for stacking‐fault contributions using a method of normalization for the coefficients suggested by Rothman and Cohen, and the results were compared to those obtained with conventional normalization. It is shown that the conclusions concerning particle size anisotropy and importance of (110) faulting in β‐AlNi remain unchanged irrespective of the normalization procedure. In addition, a modified Warren‐Averbach‐type graphical procedure is suggested for distinguishing anisotropic fault broadening from similar strain effects, which helps eliminate anisotropic strain scatter inherent to the conventional Warren‐Averbach plot and allows a direct comparison between the fault predicted and the experimental coefficients for all reflections.

Results of a series of experiments have led to the development of five (prefried and enzyme-inactivated codfish patties, prefried and enzyme- inactivated halibut patties, and halibut steak) radiation sterilized (4.5 Mrad) seafood products. Large consumer panels judged these products acceptable initially, shortly after irradiation, and after 6 months storage at 21C. The study included investigation of a large number of variables including (1) thirty commercial brands of breaded seafood products, (2) enzyme-inactivation technique, (3) a large variety of breadings and batter, and binders, (4) methods of preparing the various types of patties, (5) effects of several different anti-browning and antioxidizing agents, and (6) effects of seasoning and flavor intensifying agents. Both subjective and objective analytical techniques were used for determining the effects of the various factors on acceptability and stability of the products.