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71.
Polyamides having epoxy groups and their ring-opening derivatives were prepared and characterized, and some of their properties were investigated. Reaction conditions for the low-temperature polycondensation of cis-2,3-epoxysuccinyl chloride (ESC) with aromatic diamines and the interfacial copolycondensation of ESC and adipyl chloride (AC) with aromatic diamines were established to obtain a high molecular weight polyamide having epoxy groups. In addition, the ring-opening reactions of the epoxy groups in the polyamides were carried out with various amines in order to obtain polyamides having hydrophilic pendent groups such as amino and hydroxyl. It was found that the polyamides prepared by ring-opening reaction of the epoxy group with ethylenediamine (EDA) or ethanolamine (EA) had a higher affinity for moisture than those with hexamethylenediamine (HMD) or n-butylamine (n-BA), which might be ascribed to the distance of hydrophilic groups from the polyamide chain. Those polyamides having hydrophilic pendent groups decomposed upon heating at less than 200°C. 相似文献
72.
73.
Norimasa Kashiwagi Kohei Yamashita Hiroyuki Furuta Prof. Yoshiya Ikawa Prof. 《Chembiochem : a European journal of chemical biology》2009,10(17):2745-2752
The template effect plays important roles not only in modern synthetic and enzymatic catalysis but also in the ancient “RNA‐polypeptide (RNP) world,” which has been postulated to be a crucial stage in the origin of life. To mimic primitive template catalysis of peptide ligations by RNAs, we previously reported the design and synthesis of a ternary RNP complex in which the ligation of two peptides was significantly facilitated by a template RNA with two peptide‐binding units. However, RNA molecules also promoted the ligation reaction in a nonspecific manner through electrostatic interactions between RNA and basic peptides. In this study, we suppressed this effect by reducing the length of the original template derived from the Tetrahymena intron RNA. This modification, however, decreased the template ability for the specific reaction. As an alternative RNA that was as effective as the original template, we found that a self‐dimerizing RNA was a promising template for peptide ligation without a nonspecific effect. 相似文献
74.
Low Capture Switching Activity Test Generation for Reducing IR-Drop in At-Speed Scan Testing 总被引:1,自引:1,他引:0
Xiaoqing Wen Kohei Miyase Tatsuya Suzuki Seiji Kajihara Laung-Terng Wang Kewal K. Saluja Kozo Kinoshita 《Journal of Electronic Testing》2008,24(4):379-391
At-speed scan testing, based on ATPG and ATE, is indispensable to guarantee timing-related test quality in the DSM era. However,
at-speed scan testing may incur yield loss due to excessive IR-drop caused by high test (shift & capture) switching activity.
This paper discusses the mechanism of circuit malfunction due to IR-drop, and summarizes general approaches to reducing switching
activity, by which highlights the problem of current solutions, i.e. only reducing switching activity for one capture while
the widely used at-speed scan testing based on the launch-off-capture scheme uses two captures. This paper then proposes a
novel X-filling method, called double-capture (DC) X-filling, for generating test vectors with low and balanced capture switching activity for two captures. Applicable to dynamic & static
compaction in any ATPG system, DC X-filling can reduce IR-drop, and thus yield loss, without any circuit/clock modification, timing/circuit overhead, fault coverage
loss, and additional design effort.
相似文献
Xiaoqing WenEmail: |
75.
Pregnancy by Assisted Reproductive Technology Is Associated with Shorter Telomere Length in Neonates
Toshiko Minamoto Kentaro Nakayama Tomoka Ishibashi Masako Ishikawa Kohei Nakamura Hitomi Yamashita Kamrunnahar Shanta Hossain Mohammad Mahmud Sultana Razia Kouji Iida Gyosuke Sakashita Tsukasa Nakamura Hideyuki Kanda Satoru Kyo 《International journal of molecular sciences》2020,21(24)
Telomere length (TL) influences the development of lifestyle-related diseases, and neonatal TL may influence their prevalence. Various factors have been reported to affect neonatal TL. Although the fetus is exposed to multiple conditions in utero, the main factors affecting the shortening of neonatal TL are still not known. In this study, we sought to identify factors that influence fetal TL. A total of 578 mother-newborn pairs were included for TL analysis. TL was measured in genomic DNA extracted from cord blood samples using quantitative PCR. The clinical factors examined at enrollment included the following intrauterine environmental factors: maternal age, assisted reproductive technology (ART) used, body mass index (BMI), gestational diabetes mellitus (GDM), maternal stress, smoking, alcohol consumption, preterm delivery, small-for-gestational-age, neonatal sex, and placental weight. Univariate and multivariate regression analyses were used to verify the relationship between neonatal TL and these clinical factors. The median neonatal TL to single-copy gene ratio was 1.0. Pregnancy with ART was among the 11 factors associated with shorter neonatal TL. From multiple regression analysis, we determined that neonatal TL was significantly shorter for pregnancies in the ART group than in the other groups. We conclude that pregnancy with ART is associated with shorter neonatal TL. 相似文献
76.
77.
Solar Cells: Self‐Organized Superlattice and Phase Coexistence inside Thin Film Organometal Halide Perovskite (Adv. Mater. 8/2018) 下载免费PDF全文
78.
Kohei Murase Patrik Stenlund Peter Thomsen Jukka Lausmaa Anders Palmquist 《Journal of materials science. Materials in medicine》2018,29(7):104
In the present study, a model for simulations of removal torque experiments was developed using finite element method. The interfacial retention and fracturing of the surrounding material caused by the surface features during torque was analyzed. It was hypothesized that the progression of removal torque and the phases identified in the torque response plot represents sequential fractures at the interface. The 3-dimensional finite element model fairly accurately predicts the torque required to break the fixation of acid-etched implants, and also provides insight to how sequential fractures progress downwards along the implant side. 相似文献
79.
Niidome T Akiyama Y Shimoda K Kawano T Mori T Katayama Y Niidome Y 《Small (Weinheim an der Bergstrasse, Germany)》2008,4(7):1001-1007
Gold nanorods showing surface plasmon (SP) bands in the near-IR region are used as bioimaging probes that respond to near-IR light in mice. The SP bands of intravenously injected polyethylene glycol-modified gold nanorods are directly monitored from the mouse abdomen by using a spectrophotometer equipped with an integrating sphere. The absorbance at 900 nm from the gold nanorods immediately increases after injection and reaches a plateau. The injection of phosphatidylcholine-modified gold nanorods also increases the absorbance at 900 nm, but the absorbance decreases single exponentially with a 1.3-min half-life. In vivo spectral changes of gold nanorods depend on the surface characteristics, and can be observed in real time using simple spectroscopic measurements. 相似文献
80.
Shiomoto Kohei Yamanaka Naoaki Takahashi Tatsuro 《Communications Surveys & Tutorials, IEEE》1999,2(1):2-13
An overview is given of previously-proposed measurement-based connection admission control (CAC) methods. First we address requirements for CAC methods, and then provide a taxonomy for CAC methods. Measurement-based CAC methods are discussed in detail, classified according to the taxonomy, and compared against each other with respect to the requirements. We conclude that measurement-based CAC methods based on effective bandwidth and bufferless models are promising because they do not require complex hardware and are less dependent on assumptions regarding traffic than methods in which the effect of buffer is considered. 相似文献