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81.
Cathode buffer layers (CBLs) can effectively further the efficiency of polymer solar cells (PSCs), after optimization of the active layer. Hidden between the active layer and cathode of the inverted PSC device configuration is the critical yet often unattended vertical diffusion of the active layer components across CBL. Here, a novel methodology of contrast variation with neutron and anomalous X‐ray reflectivity to map the multicomponent depth compositions of inverted PSCs, covering from the active layer surface down to the bottom of the ZnO‐based CBL, is developed. Uniquely revealed for a high‐performance model PSC are the often overlooked porosity distributions of the ZnO‐based CBL and the differential diffusions of the polymer PTB7‐Th and fullerene derivative PC71BM of the active layer into the CBL. Interface modification of the ZnO‐based CBL with fullerene derivative PCBE? OH for size‐selective nanochannels can selectively improve the diffusion of PC71BM more than that of the polymer. The deeper penetration of PC71BM establishes a gradient distribution of fullerene derivatives over the ZnO/PCBE‐OH CBL, resulting in markedly improved electron mobility and device efficiency of the inverted PSC. The result suggests a new CBL design concept of progressive matching of the conduction bands.  相似文献   
82.
An analytical approximate solution to non-linear solute- and heat-transfer equations in the unsteady-state mushy zone of Fe-C plain steel has been obtained, assuming a linear relationship between the solid fraction and the temperature of the mushy zone. The heat transfer equations for both the solid and liquid zone along with the boundary conditions have been linked with the equations to solve the whole equations. The model predictions (e.g., the solidification constants and the effective partition ratio) agree with the generally accepted values and with a separately performed numerical analysis. The solidus temperature predicted by the model is in the intermediate range of the reported formulas. The model and Neuman’s solution are consistent in the low carbon range. A conventional numerical heat analysis (i.e., an equivalent specific heat method using the solidus temperature predicted by the model) is consistent with the model predictions for Fe-C plain steels. The model presented herein simplifies the computations to solve the solute- and heat-transfer simultaneous equations while searching for a solidus temperature as a part of the solution. Thus, this model can reduce the complexity of analyses considering the heat- and solute-transfer phenomena in the mushy zone.  相似文献   
83.
Increases in [Ca2+]i in pancreatic beta cells, resulting from Ca2+ mobilization from intracellular stores as well as Ca2+ influx from extracellular sources, are important in insulin secretion by glucose. Cyclic ADP-ribose (cADPR), accumulated in beta cells by glucose stimulation, has been postulated to serve as a second messenger for intracellular Ca2+ mobilization for insulin secretion, and CD38 is thought to be involved in the cADPR accumulation (Takasawa, S., Tohgo, A., Noguchi, N., Koguma, T., Nata, K., Sugimoto, T., Yonekura, H., and Okamoto, H. (1993) J. Biol. Chem. 268, 26052-26054). Here we created "knockout" (CD38(-/-)) mice by homologous recombination. CD38(-/-) mice developed normally but showed no increase in their glucose-induced production of cADPR in pancreatic islets. The glucose-induced [Ca2+]i rise and insulin secretion were both severely impaired in CD38(-/-) islets, whereas CD38(-/-) islets responded normally to the extracellular Ca2+ influx stimulants tolbutamide and KCl. CD38(-/-) mice showed impaired glucose tolerance, and the serum insulin level was lower than control, and these impaired phenotypes were rescued by beta cell-specific expression of CD38 cDNA. These results indicate that CD38 plays an essential role in intracellular Ca2+ mobilization by cADPR for insulin secretion.  相似文献   
84.
A water model study was carried out to understand the behavior of a molten steel and Ar gas two-phase jet issuing out of a submerged entrance nozzle in continuous casting modls. A mixture of water and air was injected horizontally from a circular pipe settled flush with the narrow face of a mold having a rectangular cross section. The water-air two-phase jet thus generated was pulled upward through the effect of buoyancy force acting on air bubbles. The deflection of the jet in the upward direction was correlated by introducing a velocity scale, which could characterize the upward moving velocity of the jet. The mean velocity and turbulence components of water flow were measured with a laser Doppler velocimeter. Empirical equations were proposed for predicting the two velocity components.  相似文献   
85.
In-situ experiments on the Fe/Al2O3 interface reaction were carried out with a high temperature X-ray diffractometer capable of measuring the X-ray diffraction pattern in 1–4s, using an imaging plate. The kinetic formation processes of the interface reaction layer were measured in short-period exposure experiments using the apparatus. The time-temperature phase diagram of Fe/Al2O3 in air was determined. Fe/Al2O4 was formed at the FeAl2O3 interface between 1595 K and 1675 K in air. The formation of FeAl2O4 obeyed the parabolic rate law. The value of the activation energy suggests that the diffusion of Al into FeAl2O4 controls the rate of formation. The results of thermal expansion coefficient measurements suggest that when a sample is cooled to room temperature, compressive strain caused by FeAl2O4 occurs on Al2O3.  相似文献   
86.
We presented 7 cases who were performed the second lobectomy for the second lung cancer after the first successful lobectomy on the contralateral lung (3 cases for right upper lobectomy + left lower lobectomy and 4 cases for right upper lobectomy + left lower lobectomy). In 6 patients, the predicted postoperative FEV1 estimated by multiplying the preoperative FEV1 by the fraction of perfusion to the contralateral lung was less than 800 ml/m2BSA, which is our first cut-off for identifying lung resection candidates. Unilateral pulmonary arterial occlusion test (UPAO) revealed that total pulmonary vascular resistance (TPVRI) in 3 of those 6 patients was lower than 700 dyne.sec.cm-5/m2BSA, our second cut-off for lung resection. More precise postlobectomy pulmonary hemodynamics in another 3 of those 6 patients were then estimated by adapting selective pulmonary occlusion test (SPAO). Since TPVRI during SPAO was lower than the cut-off value, it was suggested that second lobectomy would be feasible with low incidence of post operative cardiopulmonary complication. There was no serious complications in all 7 cases during their postoperative course. We believe that more precise prediction of postoperative pulmonary hemodynamics by adapting UPAO and SPAO could be one of the tools to minimumize postoperative cardiopulmonary complications in those patients needed second lobectomy for the second lung cancer after the first successful lobectomy on the contralateral lung even though their impaired lung fung function.  相似文献   
87.
Otoacoustic emissions evoked by electrical stimulation of the cochlea were measured in guinea pigs. Alternating current with acoustic frequencies was delivered directly to the scala tympani and the vestibuli of the basal turn by using a constant current stimulator made in our laboratory. The amplitude of the electrically evoked otoacoustic emmisson (EEOAE), which was 21.0 dB SPL in response to 2 kHz electrical stimuli of 120 microArms, was decreased gradually with anoxia of the animal and was reduced to below the noise level by extirpation of the ossiculum. The EEOAEs rose with a delay of 100 microseconds from the beginning of the stimulus, and reached maximum amplitude within three cycles. The output of EEOAE was magnified in a linear manner as the stimulus current increased from 10 to 200 microArms. The averages and standard deviations of the EEOAE output at the stimulus level of 170 microArms in six animals were 20.5 +/- 4.1 dB SPL for 1 kHz, 23.3 +/- 4.8 dB SPL for 2 kHz, 10.5 +/- 6.0 dB SPL for 3 kHz, 17.1 +/- 4.7 dB SPL for 4 kHz, 13.6 +/- 4.4 dB for 5 kHz and 18.3 +/- 4.8 dB SPL for 6 kHz. Measurement of EEOAE, in which stable responses could be obtained with simple and easy preparation, was considered a potential procedure for assessing the electromotility of the cochlear outer hair cells in vivo.  相似文献   
88.
We studied the effects of high intensity resistance exercise training on bone metabolism in 17 young adult Oriental males (23-31 years) by measuring sensitive biomarkers of bone formation and resorption. The subjects were assigned to a training group and a sedentary group. The training group followed a weight training program three times per week for 4 months. In the training group, serum osteocalcin concentration and serum bone-specific alkaline phosphatase activity were significantly increased within the first month after the beginning of resistance exercise training, and the elevated levels remained throughout the training period, while there was no significant change in plasma procollagen type-I C-terminal concentration. Urinary deoxypyridinoline excretion was transiently suppressed and returned to the initial value but was never stimulated during the 4 months. These results suggest that the resistance exercise training enhanced bone formation without prior bone resorption. In the sedentary group, there was no significant difference in bone metabolic markers except plasma procollagen type-I C-terminal, which continuously decreased during the experimental period. There were no significant changes in total and regional bone mineral density in either group. In conclusion, (1) resistance exercise training increased markers of bone formation, while it transiently suppressed a marker of bone resorption, and (2) such adaptive changes of bone metabolism to resistance exercise training occurred during the early period of the training, before changes in bone density were observable through densitometry.  相似文献   
89.
Diagnosis of endometriosis needs invasive maneuvers. New serum marker that possesses both high sensitivity and high specificity has long been desired. To establish novel serum marker for endometriosis, serum autoantibodies (autoAbs) were investigated using proteomic approach. AutoAbs in sera of endometriotic patients and healthy controls were analyzed using a mesothelial cell line, 2-DE and Western blotting. Proteins in reacted spots were identified using MALDI TOF-MS with MASCOT analysis. ELISAs were established using recombinant proteins and autoAb-titers were estimated in sera of endometriotic patients, disease and healthy controls. Several autoAbs were identified. Anti-α-enolase (Eno1)-autoAb levels in endometriotic patients were significantly elevated compared with both healthy and disease controls. Sensitivity and specificity of serum anti-Eno1-autoAb was nearly comparable to serum CA125. When anti-Eno1-autoAb and CA125 assays were combined, diagnostic sensitivity and accuracy improved. Serum anti-Eno1-autoAb can be a new serum endometriotic marker and it is useful as a supplement assay for CA125. This study validates further clinical evaluation of this novel marker.  相似文献   
90.
This paper addresses the manufacturability, yield, and reliability aspects of X Architecture interconnects (diagonal lines) in a very large scale integrated (VLSI) design that enables integrated circuit (IC) chips to become faster and smaller (area) compared to the same design in Manhattan routing. Test chips that consist of comb/serpentine, maze, via chain, as well as resistance and capacitance structures are designed and fabricated using both 130- and 90-nm copper processes. A new technique to characterize interconnect physical parameters (top and bottom line widths, metal line, and dielectric thickness) is developed that requires capacitance measurement on sets of special test structures. An excellent agreement is found between the extracted process parameters, for both diagonal and Manhattan lines, using this technique and those of SEM/FIB data. Measurements of the line resistance, capacitance, and SEM/FIB data on different types of test structures show that 1:1 design rule ratio (Manhattan versus X Architecture) is manufacturable, and the uniformity and fidelity of the diagonal lines are as good as Manhattan lines. The current generation of mask, lithography, wafer processing techniques are applicable to X Architecture designs.  相似文献   
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