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11.
A series of acrylic nonaqueous dispersions were prepared by using various kinds of butylated melamine–formaldehyde (BMF) resins as dispersant. The functional group composition of BMF to form stable dispersion was butoxy group more than 13 mol/BMF 1 mol, and methylol group ranged from 1 to 2.5 mol/BMF 1 mol. It is concluded that the anchoring of BMF to acrylic copolymer was due to the formation of covalent bond between methylol group in BMF and hydroxy group in acrylic copolymer. 相似文献
12.
Yutaka Nagai Hiroshi Kondo Noriyuki Tatsumi 《Journal of Automated Methods and Management in Chemistry》2005,2005(4):235-239
Rapid and accurate analysis of platelet count plays an important role in evaluating hemorrhagic status. Therefore, we evaluated platelet counting performance of a hematology analyzer, Celltac F (MEK-8222, Nihon Kohden Corporation, Tokyo, Japan), that
features easy use with low reagent consumption and high throughput while occupying minimal space in the clinical laboratory. All blood samples were anticoagulated with dipotassium ethylenediaminetetraacetic acid (EDTA-2K). The samples were stored
at room temperature (18^C–22^C) and tested within 4 hours of phlebotomy. We evaluated the counting ability of the Celltac F hematology analyzer by comparing it with the platelet counts obtained by the flow cytometry method that ISLH and ICSH recommended, and also the manual visual method by Unopette (Becton Dickinson Vacutainer Systems). The ICSH/ISLH reference method is based on the fact that platelets can be stained with monoclonal antibodies to CD41 and/or CD61. The dilution ratio was optimized after the precision, coincidence events, and debris counts were confirmed by the reference method. Good correlation of platelet count between the Celltac F and the ICSH/ISLH reference method (r = 0.99, and the manual visual method (r= 0.93) were obtained. The regressions were y = 0.90 x+9.0 and y=1.11x+8.4, respectively. We conclude that the Celltac F hematology analyzer for platelet counting was well suited to the ICSH/ISLH reference method for rapidness and reliability. 相似文献
13.
Masaru Takahashi Noriyuki Inoue Tatsuya Takeguchi Shinji Iwamoto Masashi Inoue Tsunenori Watanabe 《Journal of the American Ceramic Society》2006,89(7):2158-2166
The reaction of mixtures of aluminum isopropoxide and gallium acetylacetonate in 1,4-butanediol or 1,5-pentanediol at high temperatures (glycothermal reaction) directly gave the γ-Ga2 O3 –Al2 O3 solid solutions, which had high catalytic activities for selective reduction of NO using methane as the reducing agent. However, the reaction with a higher Al/(Ga+Al) charged ratio yielded the glycol derivative of boehmite as a by-product and the catalytic activity of the solid solution decreased. Therefore, synthesis of the solid solution using various glycols was examined and it was found that solid solutions with high Al contents without contamination of the glycol derivative of boehmite were obtained by using 1,6-hexanediol as a reaction medium. The solid solution exhibited a higher NO conversion than that synthesized in other glycols. 相似文献
14.
Hidemitsu Hojo Wataru Toyoshima Masayasu Tamura Noriyuki Kawamura 《Polymer Engineering and Science》1974,14(9):604-609
Particulate-filled thermosetting composites are widely used, yet little systematic work has been done on their long-term strength characteristics. In this study short-term tensile, flexural, and impact tests as well as tensile creep-rupture tests were made for unfilled and filled epoxy to clarify the effects of filler size, filler content, and temperature. Fillers used were silica, alumina particles, and glass beads. Test temperatures were varied from 25 to 110°C. As a result of short-term testing, it was found that the Petch relation held between strength and filler size if brittle fracture occurred, while a strength and filler size if brittle fracture occurred, while a strengthening effect existed when ductile fracture occurred. On creeprupture testing, a strengthening is observed with filler size and content for silica and glass beads. The Arrhenius plot of rupture time for various filler sizes and contents converges to a characteristic point corresponding to the glass transition temperature of the material. Using this relation, a modified Larson-Miller master rupture curve is proposed which can predict the long-term strength of particulate-filled thermosetting composites as functions of rupture time, temperature, filler size, and content. 相似文献
15.
Tsuji S Kasumi T Nagase K Yoshikawa E Kobayashi H Kurita N 《Journal of molecular graphics & modelling》2011,29(8):975-984
During cancer invasion, the binding of urokinase-type plasminogen activator (uPA) to its receptor (uPAR) on the surface of a cancer cell is considered a trigger for invasion. Here, we present a stable structure of the solvated complex formed between uPA and uPAR (uPA-uPAR) and investigate the specific interactions between uPA and uPAR by ab initio fragment molecular orbital (FMO) calculations. The result indicates that the electrostatic interactions between the charged amino acid residues existing in both uPA and uPAR make a large contribution to the binding between uPA and uPAR. In particular, Lys23, Lys46, Lys98 and Lys61 of uPA are found to have strong attractive interactions with uPAR. To elucidate the effect of these residues on the interactions between uPA and uPAR, we substituted each of them with the uncharged amino acid Leu and investigated the interactions between the mutated uPA and wild-type uPAR. The interaction energies indicate that Lys46 and Lys98, which bind uPA to the rim of the central ligand-binding cavity of uPAR, make greater contributions to the binding between uPA and uPAR than Lys23, which is positioned at the bottom of the ligand-binding cavity of uPAR. The effect of hydrating water molecules located between uPA and uPAR is also investigated to be significant for the specific interactions between uPA and uPAR. These results are expected to be informative for developing new peptide antagonists that block the binding of uPA to uPAR. 相似文献
16.
This paper presents a fundamental study of the connection between continuous- and discrete-time systems. Provided is a definition for discrete-time models, that is discrete-time systems with a continuous-time counterpart, whose order can be higher than that of the continuous-time system. This definition is based on a comparison in a certain sense on the time responses of continuous- and discrete-time systems. A theorem is presented for relating the higher-order discrete-time models to their continuous-time counterparts, which is an extension of a previous theorem for models with order equal to that of the continuous-time system. State-space forms are derived for models obtained through the use of a certain class of hold elements and through the use of mapping models, and these discrete-time systems are shown to be valid according to the definition. Special cases are models obtained using first-order and slewer hold devices, whose convergence to a continuous-time counterpart has not been shown mathematically before, and mapping models corresponding to two-step linear multi-step methods, which have not previously presented in the state-space form. The derived state-space forms provide a convenient way to implement these models for purposes of analysis, design, and implementation of discrete-time systems and finds applications in such areas as digital signal processing, digital simulation, and digital control. 相似文献
17.
Akihito Sagara Takahiro NomuraMasakatsu Tsubota Noriyuki OkinakaTomohiro Akiyama 《Materials Chemistry and Physics》2014
This paper describes the control of the melting point and improvement of the thermal endurance of D-mannitol (melting point Tm = 440 K) as a phase-change material (PCM) by vacuum impregnation of the PCM into nanosized pores of porous SiO2 grains. First, we examined the effects of the average pore size (DP) of porous SiO2 on Tm and latent heat (L) of PCM/SiO2 composites. Second, we investigated the thermal endurance of the composites using constant temperature kinetics based on L of the PCM and composites. Third, we performed cyclic tests of melting and freezing on the composite to evaluate leakage of the PCM. Thermophysical properties of the samples were measured by differential scanning calorimetry, and the following results were obtained: (1) The impregnation ratio of the composites was 0.91–0.99; therefore, almost all pores were completely filled with the PCM. (2) Tm shifted to lower temperature with smaller DP, reaching 413 K in case of the PCM/SiO2 composite with a DP of 11.6 nm (3) Tm was derived as a function of DP from the Gibbs–Thomson equation taking into account the existence of a nonfreezing layer on the surface of the pore wall. (4) The duration of thermal degradation of the PCM/SiO2 composite with DP = 11.6 nm was three times longer than that of the pure PCM at a temperature that is 10 K more than each melting point. (5) The PCM/SiO2 composite with DP = 11.6 nm can use as a shape-stable PCM composite without leakage of PCM. 相似文献
18.
Nguyen-Dung Tien Sono Sasaki Hiroyasu Masunaga Nobutaka Shimizu Noriyuki Igarashi Shinichi Sakurai 《Polymer》2014
Direct determination of the discrete distribution for crystalline lamellar thickness has been performed for poly(d,l-lactic acid)/poly(oxyethylene) (PDLLA/PEG) blends by conducting small-angle X-ray scattering (SAXS) measurements using synchrotron radiation. The PDLLA used was an random (racemic) copolymer of bio-based poly(l-lactic acid) (PLLA) and poly(d-lactic acid) (PDLA) with the lactide monomer ratio of l:d = 50:50. It is known that PLA is miscible with PEG in the amorphous state. In the current paper, we report comprehensive results on structural analyses of PDLLA/PEG blends in the course of heating and cooling process using SAXS to elucidate the change in the thickness distribution of the lamellae. As a consequence, it was found that the distribution of the lamellar thickness moves toward the larger value (in other words, lamellar thickening) as temperature approaches the melting point. Typically, the thickness distribution was dispersed in the range of 10–20 nm at room temperature and it changed toward 40 nm in the vicinity of the melting temperature. To the best of our knowledge, this is the first report of direct determination of the discrete distribution for the crystalline lamellar thickness and their in-situ changes in the course of the lamellar thickening process. As a result, the lamellar thickening was found to occur at much lower temperature for the blend samples with 10% and 20% of PDLLA contents as compared to the PEG 100% sample. This phenomenon can be ascribed to the melting point depression owing to the miscibility between PEG and PDLLA. Thereby, thinner lamellae were melted and thicker ones appeared at much lower temperature for the blends than for the PEG 100% sample. As for the average repeating distance (long period) of the lamellar stacks, an abrupt increase similar to the critical divergence was observed (from 25 nm to 50 nm) in the heating process. Not only for the melting behavior but also in the course of recrystallization, change in the lamellar-thickness distribution was uncovered, which shows strong hysteresis depending on what temperature the sample was cooled down from. 相似文献
19.
Tolulope Peter Saliu Nao Yazawa Kotaro Hashimoto Kenshu Miyata Ayane Kudo Mayu Horii Mion Kamesawa Thanutchaporn Kumrungsee Noriyuki Yanaka 《International journal of molecular sciences》2022,23(2)
The early detection of diabetic nephropathy (DN) in mice is necessary for the development of drugs and functional foods. The purpose of this study was to identify genes that are significantly upregulated in the early stage of DN progression and develop a novel model to non-invasively monitor disease progression within living animals using in vivo imaging technology. Streptozotocin (STZ) treatment has been widely used as a DN model; however, it also exhibits direct cytotoxicity to the kidneys. As it is important to distinguish between DN-related and STZ-induced nephropathy, in this study, we compared renal responses induced by the diabetic milieu with two types of STZ models: multiple low-dose STZ injections with a high-fat diet and two moderate-dose STZ injections to induce DN. We found 221 genes whose expression was significantly altered during DN development in both models and identified serum amyloid A3 (Saa3) as a candidate gene. Next, we applied the Saa3 promoter-driven luciferase reporter (Saa3-promoter luc mice) to these two STZ models and performed in vivo bioluminescent imaging to monitor the progression of renal pathology. In this study, to further exclude the possibility that the in vivo bioluminescence signal is related to renal cytotoxicity by STZ treatment, we injected insulin into Saa3-promoter luc mice and showed that insulin treatment could downregulate renal inflammatory responses with a decreased signal intensity of in vivo bioluminescence imaging. These results strongly suggest that Saa3 promoter activity is a potent non-invasive indicator that can be used to monitor DN progression and explore therapeutic agents and functional foods. 相似文献
20.
Inactivation of Bacillus spores by the combination of moderate heat and low hydrostatic pressure in ketchup and potage 总被引:2,自引:0,他引:2
Islam MS Inoue A Igura N Shimoda M Hayakawa I 《International journal of food microbiology》2006,107(2):124-130
The combination effect of moderate heat and low hydrostatic pressure (MHP) on the reduction of Bacillus subtilis, Bacillus coagulans and Geobacillus stearothermophilus spores in food materials (potage and ketchup) was investigated. These bacterial spores were suspended in potage (pH 7), acidified potage (pH 4), neutralized ketchup (pH 7) and ketchup (pH 4). The suspensions were treated with and without pressure (100 MPa) and temperatures of 65-85 degrees C for 3 to 12 h. The bacterial spores were inactivated by 4-8 log cycles during MHP treatment in potage, acidified potage and ketchup, whereas the spores were highly resistant to long time heat treatment in potage and neutralized ketchup. The degrees of spore destruction were mostly dependent on pH and medium composition during MHP treatment. The inactivation effect in MHP treatment was higher at the pH 7 than at pH 4 both in ketchup and potage. The bacterial spores showed higher inactivation in potage than ketchup during MHP treatment. 相似文献