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81.
我们通过对材料和制备条件的精细化处理,生产出一种在低刷新频率下无闪烁和图像迟滞现象的反射式显示器。该显示器的功耗非常低,且可在宽温度范围内工作,是未来移动显示器件的潜力平台。  相似文献   
82.
An increasing number of applications using ultraviolet radiation have renewed interest in ultraviolet photodetector research. Particularly, solar‐blind photodetectors sensitive to only deep UV (<280 nm), have attracted growing attention because of their wide applicability. Among recent advances in UV detection, nanowire (NW)‐based photodetectors seem promising, however, none of the reported devices possesses the required attributes for practical solar‐blind photodetection, namely, an efficient fabrication process, a high solar light rejection ratio, a low photocurrent noise, and a fast response. Herein, the assembly of β‐Ga2O3 NWs into high‐performance solar‐blind photodetectors by use of an efficient bridging method is reported. The device is made in a single‐step chemical vapor deposition process and has a high 250‐to‐280‐nm rejection ratio (~2 × 103), low photocurrent fluctuation (<3%), and a fast decay time (<<20 ms). Further, variations in the synthesis parameters of the NWs induce drastic changes in the photoresponse properties, which suggest a possibility for tuning the performance of the photodetectors. The efficient fabrication method and high performance of the bridged β‐Ga2O3 NW photodetectors make them highly suitable for solar‐blind photodetection.  相似文献   
83.
Sulfur and strontium isotopes (delta(34)S and (87)Sr/(86)Sr) were determined in 39 river water samples collected over three different cultivation periods (April, May, and June), and in several materials used for comparison (fertilizers, detergents, soils, irrigation and agricultural waters), to evaluate the impact of fertilizers on a small agricultural watershed of Lake Biwa, in central Japan. delta(34)S values in river water decreased (from +5.8 to -2.0 per thousand) with increasing SO(4) concentrations (3.8 to 93.2 ppm) from upstream to downstream of the watershed. Comparison of river water S isotopes with those of possible source materials indicates that the enrichment of SO(4) can be attributed to the dissolution of two kinds of fertilizers: (1) compound fertilizers commonly used in this area and (2) ammonium sulfate which is applied on a small scale. In contrast, (87)Sr/(86)Sr values of river water decreased with time from April (avg. 0.71163), through May (avg. 0.71139), to June (avg. 0.71127). The tendency of the sample plots on the (87)Sr/(86)Sr vs. 1/Sr diagram suggests a time-dependent increase in the contribution of soil water to the river, which is partly affected by the Sr-bearing fertilizers. It is suggested that a maximum of 25% of dissolved Sr is derived from these fertilizers, while more than 75% of it is of rock origin. Mass balance calculations permitted us to evaluate the proportion of fertilizer contribution in each river. Combined use of S and Sr isotopes together with concentration data could be a new environmental diagnosis technique for rivers and soils in localized watersheds.  相似文献   
84.
The developing acrosome in spermatids contains pituitary adenylate cyclase-activating polypeptide (PACAP). However, the role of the acrosomal PACAP remains unclear because it has not been detected in mature spermatids and sperm. We reinvestigated whether the sperm acrosome contains PACAP. An antiserum produced against PACAP reacted to the anterior acrosome in epididymal sperm fixed under mild conditions, suggesting that PACAP acts on oocytes and/or cumulus cells at the site of fertilization. Immunolabeling and RT-PCR demonstrated the presence of PACAP type I receptor, a PACAP-specific receptor, in postovulatory cumulus cells. To investigate the role of PACAP in fertilization, we pretreated cumulus-oocyte complexes with the polypeptide. At a low concentration of sperm, the fertilization rate was significantly enhanced by PACAP in a dose-dependent manner. Sperm penetration through the oocyte investment, cumulus layer, and zona pellucida was also enhanced by PACAP. The enhancement was probably due to an enhancement in sperm motility and the zona-induced acrosome reaction, which were stimulated by a cumulus cell-releasing factor. Indeed, PACAP treatment increased the secretion of progesterone from the cumulus-oocyte complexes. These results strongly suggest that in response to PACAP, cumulus cells release a soluble factor that probably stimulates sperm motility and the acrosome reaction, thereby promoting fertilization.  相似文献   
85.
In search of an efficient transdermal drug delivery system (TDDS), a polyhydroxyalkanoate (PHA)-based system with a polyamidoamine dendrimer was examined. Tamsulosin was used as the model drug. The dendrimer was found to act as the weak enhancer. By adding the dendrimer, the dendrimer-containing PHA matrix achieved the clinically required amount of tamsulosin permeating through the skin model. This is also the first report of the application of PHA and dendrimer to the TDDS.  相似文献   
86.
The effects of pear vinegar (PV), which was specially brewed for enhanced galacturonic acid content, on the DSS-induced ulcerative colitis (UC) mouse model were evaluated. PV improved clinical symptoms, colon inflammation, and histological tissue injury in the DSS-induced acute UC mouse model. Moreover, PV suppressed inflammation due to acute UC by suppressing the myeloperoxidase (MPO)-mediated activation of inflammatory cells such as leukocytes and decreasing the serum concentration of IL-6. Our results demonstrated the protective action of PV in the DSS-induced acute UC mouse model. On the other hand, commercial apple vinegar did not show a protective effect in the DSS-induced acute UC mouse model. Our findings indicate that PV may act as a new functional food for inflammatory bowel disease patients.  相似文献   
87.
Super environment-friendly electrodeposition paint   总被引:1,自引:0,他引:1  
Super low VOC due to new composition/reaction mechanism can minimize the environmental risk as it does not contain lead and tin, hazardous air pollutants (HAPs) and endocrine disrupters (EPA/67 items, SPEED’98/JEA/67 items) currently specified as contaminants. New EAD (electrolyzed activate deposition paint) is not the only conventional cure agent or solvent, but also the super low VOC, HAPs materials and endocrine disrupters. The electric energy used by EAD is utilized for the reaction but not for the deposition. EAD consists of two technologies. One is propargyl group change to the allene by using electrodeposition. Propargyl group is stable, but allene group is highly polymerizing. As a result, EAD had high bath stability. The other is sulfonium change to sulfide by using electrodeposition. This sulfonium salt is lost as a result of the electrolytic reduction, and hence can be irreversibly rendered non-conductive. As a result, EAD showed high throwing power.  相似文献   
88.
This paper proposes a new basic logic element for neural logic applications and demonstrates the function of neuron firing. A key device for the logic operation is the insulated-gate pn-junction device on an SOI substrate. The basic element offers an interface quite compatible to that of conventional CMOS circuits  相似文献   
89.
A new superjunction (SJ) structure offering remarkable advantages compared with the conventional SJ structure is proposed and demonstrated for a power-switching device. In the proposed structure (semi-SJ structure), an n-doped layer is connected to the bottom of the SJ structure. According to the results of experiment and simulation, the semi-SJ structure has both lower on-resistance and softer recovery of body diode than conventional SJ MOSFETs. The fabricated semi-SJ MOSFETs with breakdown voltage of 690 V realize on-resistance 28% lower than that of the conventional SJ MOSFET with same aspect ratio. The softness factor of the body diode is also improved by a factor of five. The proposed MOSFET is very attractive for H bridge topology applications, such as switching mode power supplies and small inverter systems, thanks to the low on-resistance and the soft recovery body diode.  相似文献   
90.
The thermal conductivity of the surface layer of engineering materials changes in the early stages of material degradation due to the appearance of micro‐cracks. A new method for evaluating and assessing the degree of degradation of a material using this change is proposed herein. The influence of the micro‐cracked layer on the temperature response as measured by a thermophysical handy tester was theoretically examined. By defining a thermal degradation parameter, the amount of degradation of various materials was evaluated. In order to verify this theory, fatigue tests using metallic materials were conducted. Comparisons before and after the fatigue tests were then made to establish the correlation between the density of micro‐cracks and the decrease in thermal conductivity. As a result, it was ascertained that a thermal degradation parameter can easily be estimated from a temperature response curve obtained using the tester. © 2007 Wiley Periodicals, Inc. Heat Trans Asian Res, 36(8): 501–512, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.20178  相似文献   
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