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1.
The causes of lightning outage are subdivided into direct lightning strokes and induced lightning strokes, which are identified by the characteristics of the lightning overvoltage. In the past, lightning protection devices were directed mainly toward the latter, and attention has been focused on the installation of lightning protection devices, ground wires, and reinforcement of insulators. However, lightning outages continue to occur. Thus it is extremely important to clarify the fault characteristics of lightning surges and to study the effectiveness of various lightning protection devices by considering both direct lightning stroke and induced lightning stroke in order to prevent lightning outage in the future. In this research, the electromagnetic transients program (EMTP) has been applied to the direct lightning stroke, and the induced lightning outage analysis program for multiple conductor systems has been applied to the induced lightning stroke to study the effectiveness of lightning protection devices provided by combination of various lightning protection devices. The most effective lightning protection schemes are analyzed and evaluated based on verification tests on the full scale models as well as economic considerations.  相似文献   
2.
Racemic amino acid esters were optically resolved via hydrolysis in organic solvents by the catalysis of an industrial alkaline protease, “Alcalase”. The products which were composed mainly of L-amino acids were insoluble and easily separated by filtration. The activity of the enzyme and enantiomeric excess of the products were significantly dependent on the nature of solvent and the water content in the reaction media. Generally, high values of enantiomeric excess were obtained at low water contents. Many natural and unnatural amino acids were resolved by this method.  相似文献   
3.
Aberrant glycosylation of IgA1 is involved in the development of IgA nephropathy (IgAN). There are many reports of IgAN markers focusing on the glycoform of IgA1. None have been clinically applied as a routine test. In this study, we established an automated sandwich immunoassay system for detecting aberrant glycosylated IgA1, using Wisteria floribunda agglutinin (WFA) and anti-IgA1 monoclonal antibody. The diagnostic performance as an IgAN marker was evaluated. The usefulness of WFA for immunoassays was investigated by lectin microarray. A reliable standard for quantitative immunoassay measurements was designed by modifying a purified IgA1 substrate. A validation study using multiple serum specimens was performed using the established WFA-antibody sandwich automated immunoassay. Lectin microarray results showed that WFA specifically recognized N-glycans of agglutinated IgA1 in IgAN patients. The constructed IgA1 standard exhibited a wide dynamic range and high reactivity. In the validation study, serum WFA-reactive IgA1 (WFA+-IgA1) differed significantly between healthy control subjects and IgAN patients. The findings indicate that WFA is a suitable lectin that specifically targets abnormal agglutinated IgA1 in serum. We also describe an automated immunoassay system for detecting WFA+-IgA1, focusing on N-glycans.  相似文献   
4.
In this paper, we propose a static lightpath establishment method to design low‐power all‐optical networks under the constraint of four‐wave mixing (FWM). Since the FWM causes nonlinear interchannel crosstalk, it degrades the communication quality of optical signals. The FWM crosstalk effect becomes strong in a fiber as the number of passing optical signals increases. Therefore, we should reduce the number of optical signals passing through the same fiber from the perspective of the FWM. Meanwhile, in order to enhance the power efficiency of optical amplifiers, which are deployed at each optical fiber, it is preferred that multiple optical signals are transmitted in the same fiber. In order to decrease the power consumption while keeping high communication quality, the proposed method statically selects routes, wavelengths, and fibers for each traffic demand, considering the FWM crosstalk effect and the usage efficiency of the optical amplifiers. We show the performance of the proposed method through numerical experiments.  相似文献   
5.
This paper proposes a dynamic lightpath establishment scheme considering four-wave mixing (FWM) in multifiber wavelength-division multiplexed (WDM) all-optical networks. The FWM is one of the most important physical impairments to be resolved in WDM networks because the FWM induces nonlinear inter-channel crosstalk and decays the performance of WDM networks. In WDM networks, data are transmitted via lightpaths. When the effect of FWM crosstalk is large, it is highly possible that data transmission fails even if lightpaths are correctly established. The proposed scheme aims to avoid not only the blocking of lightpath establishment but also the accumulation of FWM crosstalk by means of ingenious selection of routes, wavelengths, and fibers for lightpath establishment. In the proposed scheme, a route and a wavelength are selected for each lightpath based on wavelength availability and wavelength placement of established lightpaths. Furthermore, fibers on the route are selected based on estimated FWM power. In this paper, we show the effectiveness of the proposed scheme through simulation experiments.  相似文献   
6.
The purpose of this study is to investigate the vascular wall with a thermally self-regulating, cylindrical stent made of a low Curie temperature ferromagnetic alloy. Physiologic saline was circulated in the silicone model vessel implanted with the stent. The stent-temperature remained nearly constant for variable saline flows, saline temperatures, and magnetic flux densities. Stent implants of this type in human blood vessels could potentially enable thermotherapy and temperature determination without catheterization.  相似文献   
7.
A number of N,N′-diacylalkyldiamines were prepared from the reaction of acid chlorides with 1,8-diaminooctane and 1,12-diaminododecane and screened for anti-rust properties and antimicrobial activity in spent coolants of water-based cutting fluids. Aqueous solutions of N,N′-dihexanoyl-1,8-diaminooctane and N,N′-isobutyroyl-1,12-diaminododecane showed good anti-rust properties for water-based cutting fluids. Aqueous emulsions of N,N′-dibutyroyl-, dipentanoyl-, dihexanoyl- and dioctanoyl-1,12-diaminododecane showed good lubricities and antimicrobial activity for water-based cutting fluids.  相似文献   
8.
First-principles calculations were performed to investigate the effect of Pd concentration and oxygen vacancies on the stability of Pd at LaFeO3 surfaces. We found a much stronger tendency of Pd to segregate by taking the aggregation of Pd at LaFe1-xPdxO3-y surfaces into consideration, resulting in a pair of Pd-Pd around a vacancy. Moreover, we predicted that one oxygen-vacancy-containing FeO2-terminated surfaces would be stable at high temperatures by comparing the stability of LaFe1-xPdxO3-y surfaces, which further supports our previous conclusion that a Pd-containing perovskite catalyst should be calcined at 1,073 K or higher temperatures in air to enhance the segregation of Pd in the vicinity of surfaces to rapidly transform the Pd catalyst from oxidized to reduced states on the perovskite support.  相似文献   
9.
The recent increase in the frequency of endometrial cancer has emphasized the need for accurate diagnosis and improved treatment. The current diagnosis is still based on conventional pathological indicators, such as clinical stage, tumor differentiation, invasion depth and vascular invasion. However, the genetic mechanisms underlying endometrial cancer have gradually been determined, due to developments in molecular biology, leading to the possibility of new methods of diagnosis and treatment planning. New candidate biomarkers for endometrial cancer include those for molecular epigenetic mutations, such as microRNAs. These biomarkers may permit earlier detection of endometrial cancer and prediction of outcomes and are likely to contribute to future personalized therapy for endometrial cancer.  相似文献   
10.
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