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Palladium (Pd) present in spent electroplating solutions is concentrated by cementation with zinc (Zn) metal powder. Therefore, it is necessary to recover Pd from the cemented Pd. In this work, recovery of pure Pd(IV) compounds from the leaching solutions of the cemented Pd was investigated by using selective precipitation method. It was found that the existence of Pd(IV) in the aqueous solutions is critical for the precipitation with NH4Cl. Precipitation experiments of Pd(IV) from the synthetic aqua regia solution containing Pd(IV) and Zn(II) was tested. Afterwards, the optimum precipitation conditions were applied to recover Pd(IV) precipitates from the real H2SO4 and HCl leaching solutions containing NaClO as an oxidizing agent. The selective precipitation resulted in the recovery of extra pure (NH4)2PdCl6 from real leaching solutions under the conditions of 1:30 molar ratio of Pd(IV) to NH4Cl at 60oC within 30 min. The precipitation percentage of Pd(IV) from the H2SO4 and HCl solutions was over 99.9 and 98.2%, respectively. A simple hydrometallurgical process consisting of cementation, leaching, and precipitation was proposed for the recovery of pure Pd(IV) compounds from spent electroplating solution.

A position-sensitive pixel array silicon detector with a junction field effect transistor (JFET) switch structure is studied as a device for the direct illumination of X-ray from synchrotron light source. Considering an absorption length of silicon at an X-ray energy and a required thickness of a silicon, a 525 μ m n-type silicon wafer with high resistivity is chosen as the active volume of the detector and is depleted by applying a negative bias voltage to the junction side. The electron–hole pairs produced in an active volume by an X-ray illumination are collected on the electrodes . All pixels with one row are read in parallel and the next row is selected by the control voltage after one row has finished being read. The field shaper is introduced to produce inter-pixel isolation. We perform the simulation of the pixelated silicon position detector with JFET switch and present the characteristics of the transistor such as the drain current as a function of the voltage between the source and drain for different gate voltages. The fabrication processes of the pixel sensor with JFET switch structure based on the simulation result are also described.

The addition of minor elements is effective in designing high-strength aluminum alloys by modifying precipitation, such that clarifying the strengthening origin is highly significant. Here, 0.5 wt% Li is added in an Al–Cu–Mg alloy (AA2024 alloy), where, obvious increases in strength without reducing the ductility are achieved in both the unstretched and stretched alloys, as compared to those in the counterpart Li free alloys. The enhanced strength arising from Li addition is mainly related to the modified precipitation behavior (rather than the solute strengthening due to Li elements), in terms of Guinier–Preston–Bagaryatsky (GPB) zones and S-phase; the strengthening sources in the unstretched and stretched alloys, however, are fundamentally different. Correlative characterizations reveal that, for the unstretched alloy in the peak-aging (PA) state, the Li-addition favors a high density of uniformly distributed GPB zones while suppressing the nucleation of S-phase precipitates. Whereas, for the stretched alloys in the PA state, the Li-addition, in combination with the possible strengthening due to the T1 phase, results in refined S-phase precipitates. These modified precipitates (GPB zones and S-phase) are decorated with Li enrichments, which are believed to be correlated with the proposed mechanism of the Li-Vacancy complex. Thus, elucidating the origin of strengthening in Li-added Al–Cu–Mg alloys under both unstretched and stretched conditions, is expected to provide basic insights into the strengthening mechanisms in other high-strength Al alloys when Li is added as the minor element.

Local heat transfer characteristics on a circular cylinder subject to a circular impinging jet in crossflow are studied experimentally at a fixed jet Reynolds number of Rej = 20,000. Three cylinder-to-jet diameter ratios, D/Dj = 0.5, 2.0, and 5.0 are selected for a fixed jet diameter Dj. As reference, heat removal from a flat plate (having D/Dj = ∞) by the same circular impinging jet is also measured. Results reveal that local surface heat transfer characteristics are governed separately by the mechanisms for two limiting configurations. Smaller cylinders (than the circular jet diameter e.g., D/Dj ≤ 0.5) behave as if immersed in uniform free-stream – flow separation causes the local minimum heat transfer. Larger cylinders (than the circular jet diameter e.g., D/Dj ≥ 2.0) follow the local heat transfer characteristics observable on a flat plate subject to a circular impinging jet – laminar to turbulent flow transition induces local heat transfer peaks.

Contour extracting plays an important role in image processing and computer vision, and it’s one of the most important components in low level processing. Based on many tests, this paper applies hue and texture as feature combined with mathematical morphology to have a rough segmentation of homogeneous objects, then restores the obtained contour based on h component. Tests prove that acceptable contour can be obtained. Compared with traditional method of contour extracting, the algorithm mentioned here includes self-differing, contour restoring based on hue and so on, so it has better robustness to light variation.

Ferromagnet–metal-type composites, La0.7Ca0.3MnO3(LCMO)–Cu, have been fabricated by a three-step route. We got LCMO powder using the conventional solid state method. Then, LCMO powders coated by Cu are obtained using a novel electroless plating technique, in which the contents of copper are controlled by changing the plating time. Finally these powders are pelletized and then sintered at different temperatures in argon. The powders coated by Cu are characterized by x-ray powder diffraction and scanning electron microscope. The temperature dependence of resistivity and the magnetoresistance in the applied field of 3000 Oe are measured. It is observed that the metal–insulator transition temperature (Tp) is improved above 20 K approximately up to 280 K compared with that of LCMO powder using the conventional solid state method without being coated by Cu; meanwhile, a second broad peak occurs in low temperature in the resistivity-temperature curve when sintering temperature is changed. Also an anisotropic magnetoresistance effect is observed.

A modified synthesis method of La0.67Ca0.33MnO3 by high energy ball milling and post sintering is reported. The characteristics of samples from this modified method are also studied. The new synthesis method has some advantages including reducing the synthesis procedure into two simple steps, shortening the sintering time, and obtaining similar properties compared with conventional synthesis method. High energy ball milling was employed for 10 h to refine the starting materials into a sub-micron particle size (for comparison, samples milled for 30 and 50 h were also synthesized); during the process, ethanol was added as a milling medium for avoiding amorphization or crystallization, as well as suspending the starting powders for more profound milling. Finally, the as-milled powder was sintered in air to crystallize. The samples show metal-to-insulator transitions at around 260 K, with grain size from 200 nm to 8 μm, and exhibit large magnetoresistance up to 21% at a magnetic field of 3000 Oe near the transition temperature. The possible mechanism is discussed.

The varied bonding state and microstructure characterization were discussed for carbon–boron nitrogen (CBN) with abundant phase structure and nanostructure, which were synthesized directly by mechanical alloying technique at room temperature. According to the results of SEM and X-ray photoelectron spectroscopy (XPS) of CBN with different ball milling time, it is substantiated that the bonding state and microstructure for CBN were closely related to the ball milling time. With the increase of the ball milling time, some new chemical bonding states of CBN were observed, which implies that some new bonding state and microstructures have been formed. The results of XPS are accordance with that of X-ray diffraction of CBN.

CBN ternary compounds with nano-structure have been prepared directly by a mechanical alloying technique at room temperature. The characteristic and formation mechanism of CBN are discussed. The nano-sheets and nano-layered rods of CBN are observed according to the morphology of scanning electron microscopy. It is substantiated that the microstructure of CBN was closely related to the ball milling time and the ball milling condition according to the results of X-ray diffraction of CBN with different ball milling time. After ball milling for 60 and 90 h, some new diffraction peaks are observed, which implies that some unknown microstructure and phase separation are induced in the reactive ball milling of CBN. The results of XRD are in accordance with that of X-ray photoelectron spectroscopy of CBN before ball milling and after ball milling for 90 h.

The purpose of this study was to investigate the catalytic role of granular activated carbon (GAC), and metal (Mn or Fe) doped-GAC, on the transformation of ozone into more reactive secondary radicals, such as hydroxyl radicals (.OH), for the treatment of wastewater. The GAC doped with Mn showed the highest catalytic performance in terms of ozone decomposition into OH radicals. Likewise, activated carbon alone accelerated the ozone decomposition, resulting in the formation of .OH radicals. In the presence of promoters, the ozone depletion rate was enhanced further by the Mn-GAC catalyst system, even under aqueous acidic pH conditions.

Probing the deep-depletion mode high-frequency capacitance-voltage (C-V) responses of MOS capacitors under photonic excitation, the distribution (D/sub it/) of the interface states (E/sub t/) at Si/SiO/sub 2/ heterojunctions was characterized. A photon energy E/sub ph/=0.943 eV (less than the silicon energy bandgap) was employed for the characterization of interface states in the photoresponsive energy band. In order to limit the photonic contribution to the change in the gate capacitance by excess carriers excited only from the interface states, a fast dc sweep rate (50 mV/s) with a high-frequency (500 kHz) small-signal was applied. Photonic C-V responses with a slow dc sweep for E/sub ph/=0.943 eV and a fast sweep for E/sub ph/=1.481 eV have been also provided for a comparison. Modulating the surface potential with the gate bias, a U-shaped distribution of D/sub it/ was obtained over the photoresponsive energy band in (E/sub C/-E/sub ph/)

Buckling and free vibration of stepped laminated composite beams were studied using simple higher-order theory (SHOT) which assumes a cubic distribution for the displacement field through the thickness. The results were compared to those from Euler-Bernoulli beam theory and Timoshenko's first-order shear beam theory. The results from SHOT did not show significant differences to those from Timoshenko theory for a wide range of aspect ratios of the beam geometry and material properties. In addition, the results from SHOT did not necessarily show more compliant results than those from Timoshenko beam theory. A two-dimensional (2-D) elasticity solution was obtained for the buckling of clamped-clamped beams to further investigate this phenomenon. The 1-D shear beam theories of Timoshenko and SHOT resulted in more compliant responses than 2-D solutions. The shear beam theories approached the 2-D solution from below while Euler-Bernoulli beam theory approached the 2-D solution from above.

Farnesyl diphosphatase (FDPase; EC 3.1.7.1) produces farnesol from farnesyl diphosphate (FDP) in a reaction that does not require Mg2+. This report shows that FDPase is constitutively expressed at a high level in the soluble and the microsomal fractions of Datura stramonium. Soluble and microsomal FDPase have a similar pH optimum (5.0 – 6.0) and a similar substrate specificity. Geranyl diphosphate (GDP) and geranylgeranyl diphosphate (GGDP) compete for FDP, but isopentenyl diphosphate (IDP), ATP, and para-nitrophenyl phosphate do not. Soluble FDPase activity was highest in fruit and flower followed by root, and leaf.

Cisplatin, a chemotherapeutic agent for treating various solid tumors, produces hearing loss in approximately half a million cancer patients annually in the United States. In the course of developing a new protective agent against cisplatin-induced ototoxicity, we have been interested in a novel synthetic compound, 3-amino-3-(4-fluoro-phenyl)-1H-quinoline-2,4-dione (KR-22332). The effect of KR-22332 on cisplatin-induced cytotoxicity was analyzed in vitro in an organ of Corti-derived cell line (HEI-OC1), and in vivo in a zebrafish and rat model. Cisplatin-induced apoptosis, reactive oxygen species (ROS) generation and altered mitochondrial membrane potential (MMP) in HEI-OC1 cells were observed. KR-22332 significantly inhibited cisplatin-induced apoptosis, change of MMP, and intracellular ROS generation. KR-22332 markedly attenuated the cisplatin-induced loss and changes of auditory neuromasts in the zebrafish. Transtympanic administration of KR-22332 in a rat model was protective against cisplatin-induced hearing loss, as determined by click-evoked auditory brainstem response (p0.01). Tissue terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling of rat cochlea demonstrated that KR-22332 blocked cisplatin-induced apoptosis. In addition, transtympanic administration of KR-22332 inhibited cisplatin-induced nicotinamide adenine dinucleotide phosphate-oxidase 3 (NOX3) overexpression in the rat cochlea. KR-22332 significantly reduced the expression of p-53, mitogen-activated protein kinases, caspase 3, and tumor necrosis factor-α compared to their significant increase after cisplatin treatment. The results of this study suggest that KR-22332 may prevent ototoxicity caused by the administration of cisplatin through the inhibition of mitochondrial dysfunction and the suppression of ROS generation. These novel findings implicate KR-22332 as a potential candidate for protective agent against cisplatin-induced ototoxicity.

This paper aims to develop and demonstrate intelligent diagnosis system that ensures effective supporting the decision-maker in determining the cause and potential solutions to unpredictable problems or events detected by monitoring factory-wide operating processes. The algorithm for accomplishing rapid, cost-effective, and high reliable diagnosis system is well-designed with C++ as an object-oriented programming language under Windows OS platform. A windows-based prototype system for intelligent diagnosis system with real-time status data collected from shop floor is also suggested and demonstrated by using C++ programming language and C4.5 learning algorithm.

New information technology and an upgrade process are needed for a nuclear plant to have the capability of performing the extended scope of a plant information system. The current modular component technology is to be used for a next generation plant to achieve the extended plant information system function. This paper describes the realization of the new information system function by the Web interface technique in the project for the development of a liquid metal reactor, KALIMER (Korea Advanced Liquid Metal Reactor). The current plant information system in the KALIMER project, which currently supports design process, consists of a design information system, analysis information system, user interface management system and plant information database. The design information system manages all design documents and data in the design process. The analysis information system analyzes calculation results made for plant safety and performance. The user interface management system manages the interface among hardware, software and users. Using these systems supported, remote users can have access to design data and process data conveniently by the Web and the systems reduce the time and cost required for the access, and also improve data accuracy.

Pluripotent stem cells have been generated from two embryonic sources: ES cells generated from ICM of blastocyst stage embryos, and embryonic germ (EG) cells generated from primordial germ cells (PGCs). Both ES and EG cells are pluripotent and exhibit important characteristics such as high alkaline phosphatase (AP) activity, multicellular colony formation, normal and stable karyotype, continuous passaging ability, and capacity to differentiate into three embryonic germ layers. This study was performed to establish the culture system for mouse EG cells derived from mouse PGCs. PGCs collected from the genital ridge of Day 11.5, 12.5, and 13.5 mouse embryos (C57BL/6 × DBA/2) were cultured and subsequently passaged on mitotically inactivated STO feeder cell layer. Cells were grown in Dulbecco's modified eagle medium (DMEM) supplemented with 15% fetal bovine serum (FBS), 0.1 mM nonessential amino acids, 0.1 mM 2-mercaptoethanol, 2 mM glutamine, 100 IU/mL of penicillin, 100 μg/mL of streptomycin, 1,000 units/mL of leukemia inhibiting factor (LIF), 6 ng/mL of SCF, and 10 ng/mL of bFGF at culture conditions of 5% CO2 in air, 95% relative humidity, 37°C temperature. Cells were routinely passaged every 3–4 days. Over a period of 7–10 days in primary culture, PGCs proliferated to form small, densely packed, multicellular colonies consisting of AP-positive cells that morphologically resembled undifferentiated ES cells. RT-PCR analysis confirmed mRNA expression of transcription factors Oct-4 and Nanog in these cells. Cultured cells could be maintained on the feeder cell layer for at least 10 passages and still retain normal karyotype. These results suggest that cell lines derived from mouse primordial germ cells are presumably EG cell lines and could be useful for transgenic animal production and ES cell study.

Quantitative cytophotometry was used to monitor T-2 toxin-induced alterations in azure B-RNA and Coomassie-total cell protein in supraoptic-magnocellular neurons of rat hypothalami. Thirty male Sprague-Dawley rats (200–220g) were given a single i.p. injection of T-2 toxin (0.5, 0.75, 1.00 and 1.50 × LD 50 ), a trichothecene mycotoxin; rats were decapitated 8 hours post-dosing. After stoichiometric azure B-RNA and Coomassie-protein staining of brain sections, scanning-integrating microdensitometry was used to quantify toxin-induced alterations in these well established indices of neuronal toxicity. Within the magnocellular neurons of the supraoptic nuclei, significant reductions in azure B-RNA reactivity were observed in the 0.75, 1.00 and 1.50 × LD 50 groups (i.e. 11%, 13% and 8%, respectively); no differences in RNA levels were observed between controls and the 0.50 × LD 50 group. In addition, a decrease in Coomassie-total cell protein was seen in animals receiving 0.50, 0.75 and 1.50 × LD 50 T-2 toxin (i.e. 33%, 21% and 12%, respectively); however, toxin administration did not alter protein levels in the 1.00 × LD 50 group. Furthermore, a dose-dependent decrease in systolic blood pressure was observed at 8 hr. post-injections (i.e., approximately −39%, −52%, −66% and −64% for the 0.50, 0.75, 1.00 and 1.50 × LD 50 groups, respectively). Additional observations include pronounced polydipsia, ascites, abdominal and subdural hemorrhage, and horripilation (piloerection) in experimental groups. It is postulated that the T-2 toxin-induced reductions in azure B-RNA and Coomassie-protein represent an early indication of impaired metabolic activity. Since these neurons are important sites of vasopressin (antidiuretic hormone) synthesis, these data suggest an impaired osmoregulatory ability. The pronounced polydipsia which occurred shortly after intoxication is further evidence of this impairment. Although these findings do not provide insight relating to the mechanism of osmoregulatory disruption, it is advanced that the supraoptic-magnocellular compartment represents an important site in T-2 toxin mycotoxicosis. Moreover, these findings support previous claims that T-2 toxin intoxication may critically impair the vasopressinergic response to toxin-induced cardiovascular collapse.

Abstract Bottom hole buildup pressures on three Wyoming pumping wells have been determined based on liquid level in the annulus as determined from a computerized acoustic device. These buildup data correspond to a naturally fractured reservoir which produces oil, gas and water. Basic formulations and three case histories are presented:The case of a well with after flow effects where the buildup data are properly matched using type curves for dual-porosity systems with restricted (pseudo steady state) interporosity flow and the pressure derivative.The case of a stimulated well in a naturally fractured reservoir. In this situation a conventional log-log crossplot of delta p vs. time results in two parallel straight lines with slopes equal to 0.5. Separation between the two lines allows calculation of the storativity ratio, omega.The case of a well in a layered naturally fractured reservoir with variable afterflow effects. In this case a log-log plot of delta p vs. time shows two parallel straight lines with slopes equal to 1.0. A good match of the data is obtained with a dual-porosity model and the pressure derivative starting at the second 1.0 slope straight line. Acquisition of the raw data, conversion into bottom hole buildup pressures, and analysis utilizing dual-porosity models are presented in detail. It is concluded that pumping wells in naturally fractured reservoirs can be properly evaluated when all phases flowing are taken into account. The same procedure and formulations presented in this work can be utilized for analysis of conventional single-porosity reservoirs by making Warren and Root's omega equal to 1.0. DESCRIPTION OF EQUIPMENT The Automatic Acoustic Bottomhole Pressure system determines the depth to the liquid level, and measures and records the casinghead pressure in a well, unattended. The frequency of data point collection may be specified by the operator. The equipment consists of an electronic package, a wellhead assembly, interconnecting cables, a 12 volt battery, and a small gas supply container. P. 577^