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991.
Saito Y Ichihara M Okamoto Y Gong X Kuroda C Tori M 《Natural product communications》2012,7(4):423-426
Four new eremophilane-type sesquiterpenoid alcohols were isolated from Cremanthodium helianthus collected in China and their structures established on the basis of spectroscopic analyses. All of them had 9-en-8-one partial structures with one more double bond either delta11, delta11(13), or delta7(11). Two of them had a hydroxy group at C-1 position. 相似文献
992.
Hirota H Horiguchi Y Kawaii S Kuroda C Hanai R Gong X 《Natural product communications》2012,7(4):451-454
The chemical constituents of the roots of two Ligularia lankongensis samples collected in Yunnan and Sichuan Provinces, China, were investigated, together with the DNA sequence of the atpB-rbcL and ITS regions. Four new highly oxygenated bisabolane-type sesquiterpenes (1 - 4) were obtained. Intraspecific diversity in the DNA sequence was found to be limited. 相似文献
993.
This paper presents the theoretical analysis of a multilayered magneto-electro-thermoelastic hollow sphere under unsteady and uniform surface heating. We obtain the exact solution of the transient thermal stress problem of the multilayered magneto-electro-thermoelastic hollow sphere in the spherically symmetric state. As an illustration, we perform numerical calculations of a two-layered composite hollow sphere made of piezoelectric and magnetostrictive materials and investigate the numerical results for temperature change, displacement, stress, and electric and magnetic potential distributions in the transient state are shown in figures. 相似文献
994.
Conversations must be shielded from people in an adjacent room if they include confidential information. Word intelligibility tests were performed in a total of 185 sound fields to examine the relationship between sound insulation performance and the degree of conversation leakage. The parameters of the test sound fields were background noise level in the adjacent room and the level difference between the two rooms. The background noise level was varied from 30 to 50 dB (A-weighted). The level difference was parametrically varied in terms of eight frequency characteristics and 10 absolute values. The results showed that word intelligibility scores were strongly correlated with the A-weighted speech-to-noise ratio and SNRuni32. Equal-intelligibility contours, which can easily show the weighted level difference and A-weighted background noise level required to achieve a certain level of word intelligibility scores, were obtained from a multiple logistic regression analysis. 相似文献
995.
Ishida T Alexandrov M Nishimura T Minakawa K Hirota R Sekiguchi K Kohyama N Kuroda A 《Journal of fluorescence》2012,22(1):357-363
Fluorescence microscopy (FM) has recently been applied to the detection of airborne asbestos fibers that can cause asbestosis,
mesothelioma and lung cancer. In our previous studies, we discovered that the E. coli protein DksA specifically binds to the most commonly used type of asbestos, chrysotile. We also demonstrated that fluorescent-labeled
DksA enabled far more specific and sensitive detection of airborne asbestos fibers than conventional phase contrast microscopy
(PCM). However, the actual diameter of the thinnest asbestos fibers visualized under the FM platform was unclear, as their
dimensions were below the resolution of optical microscopy. Here, we used correlative microscopy (scanning electron microscopy
[SEM] in combination with FM) to measure the actual diameters of asbestos fibers visualized under the FM platform with fluorescent-labeled
DksA as a probe. Our analysis revealed that FM offers sufficient sensitivity to detect chrysotile fibrils as thin as 30–35 nm.
We therefore conclude that as an analytical method, FM has the potential to detect all countable asbestos fibers in air samples,
thus approaching the sensitivity of SEM. By visualizing thin asbestos fibers at approximately tenfold lower magnifications,
FM enables markedly more rapid counting of fibers than SEM. Thus, fluorescence microscopy represents an advanced analytical
tool for asbestos detection and monitoring. 相似文献
996.
Cationic and amphiphilic polymers are known to exert broad-spectrum antibacterial activity by a putative mechanism of membrane disruption. Typically, nonspecific binding to hydrophobic components of the complex biological milieu, such as globular proteins, is considered a deterrent to the successful application of such polymers. To evaluate the extent to which serum deactivates antibacterial polymethacrylates, we compared their minimum inhibitory concentrations in the presence and absence of fetal bovine serum. Surprisingly, we discovered that the addition of fetal bovine serum (FBS) to the assay media in fact enhances the antimicrobial activity of polymers against Gram-positive bacteria S. aureus, whereas the opposite is the case for Gram-negative E. coli. Here, we present these unexpected trends and develop a hypothesis to potentially explain this unusual phenomenon. 相似文献
997.
Takafumi Kinuta Yuko Kise Kensaku Kamon Nobuo Tajima Tomohiro Sato Reiko Kuroda Yoshio Matsubara Yoshitane Imai 《Tetrahedron letters》2009,50(42):5786-5789
A novel charge-transfer (CT) host system is developed using CT complexes composed of rac-3,3′-dihydroxy-1,1′-bi-2-naphthol and 1,1′-dibenzyl-4,4′-bipyridinium dichloride. This CT host complex has a 1D channel-like cavity in which guest (MeOH and EtOH) molecules can be discharged and adsorbed. The color and DRS of the CT crystals change according to the presence of guest molecules in the host complex. 相似文献
998.
We found new plasticizers with high molecular weight and low mobility for poly(lactic acid) (PLA). The new plasticizers are polyester-diols (PED) with nominal molecular weight 2000. Temperature dependence of oscillatory tensile moduli of PLA/PED blends in solid states was measured and miscible pairs of the blends were found. The miscible pairs are PLA/poly(ethylene adipate) and PLA/poly(diethylene adipate). Observation by scanning electron microscope and results of differential scanning calorimetry also indicate that these blends are miscible with PLA at weight ratio of PED less than or equal to 20%. In these blends, glass transition temperature is significantly lower than that of PLA. On the other hand, poly(butylene adipate) and poly(hexamethylene adipate) are partially miscible with PLA at weight ratio of PED 20%. The difference of the miscibility is discussed in terms of solubility parameter, which is calculated using the method by Small and configurational entropy. 相似文献
999.
The hydrophobic effect in the reaction of a homoallyl alcohol with an aldehyde (Yadav's reaction system) under aqueous conditions in the presence of an acidic surfactant was studied indicating the presence of the alkyl‐substituent effect, although not a dramatic one. The DBSA‐promoted reaction proceeds relatively faster when both the homoallyl alcohol and the aldehyde carry a cycloalkyl group (DBSA=4‐dodecylbenzenesulfonic acid). In contrast, the reaction of the substrates having an unbranched alkyl group is relatively more favorable in SDS/HCl than in DBSA (SDS=sodium dodecyl sulfate). 相似文献
1000.