An integrated 16/spl times/16 PVDF pyroelectric sensor array

This paper presents a fully integrated PVDF-on-silicon pyroelectric sensor array. The pyroelectric sensor has two main features: a subpixel low noise charge amplifier and a self-absorbing layered structure. The integrated low noise charge amplifier is implemented in a standard CMOS process technology. It is located directly under the sensing structure, maximizing the pixel fill factor. The self-absorbing pyroelectric sensor is a three-layer stack, consisting of a conductive polymer as an absorber layer and front electrode, a thin PVDF film as the pyroelectric material, and a rear metal layer acting as a reflector layer and rear electrode. The manufacture of the pyroelectric sensor array requires five maskless post-CMOS processing steps and is compatible with any n-well, double metal, double polysilicon, CMOS process. The array has an average pixel voltage sensitivity of 2200 V/W at 100 Hz, an NEP of 2.4/spl times/10/sup -11/ W//spl radic/Hz at 100 Hz, and a specific detectivity of 4.4/spl times/10/sup 8/ cm /spl radic/Hz/W at 100 Hz.     

A novel method for determining calibration and behavior of PVDF ultrasonic hydrophone probes in the frequency range up to 100 MHz

A new calibration technique for PVDF ultrasonic hydrophone probes is described. Current implementation of the technique allows determination of hydrophone frequency response between 2 and 100 MHz and is based on the comparison of theoretically predicted and experimentally determined pressure-time waveforms produced by a focused, circular source. The simulation model was derived from the time domain algorithm that solves the non linear KZK (Khokhlov-Zabolotskaya-Kuznetsov) equation describing acoustic wave propagation. The calibration technique data were experimentally verified using independent calibration procedures in the frequency range from 2 to 40 MHz using a combined time delay spectrometry and reciprocity approach or calibration data provided by the National Physical Laboratory (NPL), UK. The results of verification indicated good agreement between the results obtained using KZK and the above-mentioned independent calibration techniques from 2 to 40 MHz, with the maximum discrepancy of 18% at 30 MHz. The frequency responses obtained using different hydrophone designs, including several membrane and needle probes, are presented, and it is shown that the technique developed provides a desirable tool for independent verification of primary calibration techniques such as those based on optical interferometry. Fundamental limitations of the presented calibration method are also examined.     

Fast algorithms for data reduction in modern optical three-dimensional profile measurement systems with MMX technology

Confocal microscopy and white-light interferometry are two promising methods for the three-dimensional microstructure analysis of technical and biologic specimens. For both methods the specimen is scanned through the focus position by means of an actuator. A large series of intensity frames is acquired. These data are used for the final calculation of the topography. We demonstrate that the multimedia extended (MMX) instruction set, which is implemented in modern Intel microprocessors, can be used for effective real-time preprocessing and for fast evaluation algorithms. So this new technique enables the implementation of more-complex algorithms with acceptable run times even on standard computer technology. The possibilities of the MMX instruction set are discussed for confocal microscopy and for white-light interferometry.     

Nonmonotonic generalization bias of Gaussian mixture models

Theories of learning and generalization hold that the generalization bias, defined as the difference between the training error and the generalization error, increases on average with the number of adaptive parameters. This article, however, shows that this general tendency is violated for a gaussian mixture model. For temperatures just below the first symmetry breaking point, the effective number of adaptive parameters increases and the generalization bias decreases. We compute the dependence of the neural information criterion on temperature around the symmetry breaking. Our results are confirmed by numerical cross-validation experiments.     

ANALYSIS OF STRESS AND TEMPERATURE IN THE CONFORM FORMING PROCESS——FOUNDATION THEORY

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Non-destructive and non-invasive observation of friction and wear of human joints and of fracture initiation by acoustic emission

Quality control in orthopaedic diagnostics according to DIN EN ISO 9000ff requires methods of non-destructive process control, which do not harm the patient by radiation or by invasive examinations. To obtain an improvement in health economy, quality-controlled and non-destructive measurements have to be introduced into the diagnostics and therapy of human joints and bones. A non-invasive evaluation of the state of wear of human joints and of the cracking tendency of bones is, as of today's point of knowledge, not established. The analysis of acoustic emission signals allows the prediction of bone rupture far below the fracture load. The evaluation of dry and wet bone samples revealed that it is possible to conclude from crack initiation to the bone strength and thus to predict the probability of bone rupture.     

Ultratrace and isotope analysis of long-lived radionuclides by inductively coupled plasma quadrupole mass spectrometry using a direct injection high efficiency nebulizer

The direct injection high efficiency nebulizer (DIHEN) was explored for the ultrasensitive determination of long-lived radionuclides ((226)Ra, (230)Th, (237)Np, (238)U, (239)Pu, and (241)Am) and for precise isotope analysis by inductively coupled plasma mass spectrometry (ICPMS). The DIHEN was used at low solution uptake rates (1-100 μL/min) without a spray chamber. Optimal sensitivity (e.g., (238)U, 230 MHz/ppm; (230)Th, 190 MHz/ppm; and (239)Pu, 184 MHz/ppm) was achieved at low nebulizer gas flow rates (0.16 L/min), high rf power (1450 W), and low solution uptake rates (100 μL/min). The optimum parameters varied slightly for the two DIHENs tested. The detection limits of long-lived radionuclides in aqueous solutions varied from 0.012 to 0.11 ng/L. The sensitivity of the DIHEN was improved by a factor of 3 to 5 compared with that of a microconcentric nebulizer (MicroMist used with a minicyclonic spray chamber at a solution uptake rate of 85 μL/min) and a factor of 1.5 to 4 compared with that of a conventional nebulizer (cross-flow used with a Scott type spray chamber at a solution uptake rate of 1 mL/min). The precision of the DIHEN ranged from 0.5 to 1.7% RSD (N = 3) for all measurements at the 10 ng/L concentration level (～3 pg sample size). The sensitivity decreased to 10 MHz/ppm at a solution uptake rate of 1 μL/min. The precision was about 5% RSD at a sample size of 30 fg for each long-lived radionuclide by the DIHEN-ICPMS method. The oxide to atom ratios were less than 0.05 (except ThO(+)/Th(+) ) and decreased under the optimum conditions in the following sequence: ThO(+)/Th(+) > UO(+)/U(+) > NpO(+)/Np(+) > PuO(+)/Pu(+) > AmO(+)/Am(+) > RaO(+)/Ra(+). Atomic and oxide ions were used as analyte ions for ultratrace and isotope analyses of long-lived radionuclides in environmental and radioactive waste samples. The analytical methods developed were applied to the determination of long-lived radionuclides and isotope ratio measurements in different radioactive waste and environmental samples using the DIHEN in combination with quadrupole ICPMS. For instance, the (240)Pu/(239)Pu isotope ratio was measured in a radioactive waste sample at a plutonium concentration of 12 ng/L. This demonstrates a main advantage of DIHEN-ICPMS compared with α-spectrometry, which cannot be used to selectively determine (239)Pu and (240)Pu because of similar α energies (5.244 and 5.255 MeV, respectively).     

In-line catalytic derivatization method for selective detection of chlorinated aromatics with a hyphenated gas chromatography/laser mass spectrometry technique: a concept for comprehensive detection of isomeric ensembles

The combination of gas chromatography (GC) and laser-based resonance-enhanced multiphoton ionization-time-of-flight mass spectrometry (REMPI-TOFMS) represents a three-dimensional analytical method, using the gas chromatographic retention time, the wavelength of the ionization laser for REMPI, and the molecular mass as analytical parameters. In this work, a novel analytical scheme for detection of chlorinated aromatic compounds, including isomeric ensembles, by GC/REMPI-TOFMS is presented. The concept uses an in-line hydrodechlorination catalyst for post- or precolumn derivatization of chlorinated aromatic compounds. The chlorinated aromatics are quantitatively reduced, forming their respective aromatic skeletons. These aromatic skeletons are detected selectively by REMPI-TOFMS. The first results for substance class selective detection of chlorinated benzene isomers are given, and potential applications in the field of the analysis of compounds such as polychlorinated dibenzo-p-dioxins and -furans are discussed.     

Radiorecovery Activity of Dicopper(II) Tetrakis(3,5-Diiso propylsalicylate) Includes Recovery of Radiation-Induced Loss of Body Mass and Impaired Mouse Locomotion

Dicopper(II) tetrakis(3,5-diisopropylsalicylate), [Cu(II)(2)(3,5-DIPS)(4)], is effective in increasing survival of lethally irradiated mice when it is administered after irradiation. The possibility that this radiorecovery activity might also facilitate recovery from radiation-induced impaired increase in body mass and locomotion was examined. Cu(II)(2)(3,5-DIPS)(4) was used to treat LD 50/30 gamma irradiated female C57BL/6 mice after irradiation. A dose of 0, 5, 10, or 20 mumol Cu(II)(2) (3, 5-DIPS)(4) /kilogram of body mass was administered subcutaneously 3 hrs after LD 50/30 irradiation and change in body mass and locomotor activity measured daily throughout the 30 day post-irradiation period. Treatment with 5, 10, or 20 mumol Cu(II)(2) (3,5-DIPS)(4) /kg of body mass increased survival, which was statistically significant for the 10 mumol /kg of body mass-treated group compared to the vehicle-treated group (P<0.05), significantly (P<0.05) increased recovery of locomotion from days 13 to 15 post-irradiation onward for all treated groups compared to vehicle-treated mice, and increased recovery of body mass gain from day 14 onward for the 20 mumol /kg of body mass-treated group (P<0.001) and day 21, although not statistically significant, for the 10 mumol /kg of body mass-treated group. There were no statistically significant differences between the increase in survival, recovered increase in body mass, and recovered increase in locomotion for mice treated with 10 mumol or 20 mumol Cu(II)(2)(3,5-DIPS)(4) /kg on day 30 post-irradiation. It is concluded that Cu(II)(2)(3,5-DIPS)(4) in addition to increasing survival of irradiated mice increases the rate of recovery of radiation-induced decrease in body mass and locomotion.