Anti-Salmonella activity of alkyl gallates   总被引：5，自引：0，他引：5  

Kubo I  Fujita K  Nihei K 《Journal of agricultural and food chemistry》2002,50(23):6692-6696

A series of alkyl gallates (3,4,5-trihydroxybenzoates) was synthesized and tested for their antibacterial activity against Salmonella choleraesuis. Nonyl (C(9)) and octyl (C(8)) gallates were noted to be the most effective against this food-borne bacterium, each with a minimum bactericidal concentration (MBC) of 12.5 microg/mL, followed by decyl (C(10)) gallate, with a MBC of 25 microg/mL. Dodecyl (C(12)) gallate exhibited activity against S. choleraesuis, with a MBC of 50 microg/mL. Propyl (C(3)) gallate showed no activity against S. choleraesuis up to 3200 microg/mL. The length of the alkyl group is not a major contributor but plays a role in eliciting the activity to a large extent. The same series of alkyl gallates, regardless of alkyl chain length, all showed nearly the same potent scavenging activity on the 1,1-diphenyl-2-picrylhydrazyl radical, indicating that the length of the alkyl group is not associated with the activity.  相似文献   

Volatile aldehydes are promising broad-spectrum postharvest insecticides     

Hammond DG  Rangel S  Kubo I 《Journal of agricultural and food chemistry》2000,48(9):4410-4417

A variety of naturally occurring aldehydes common in plants have been evaluated for their insecticidal activity and for phytotoxicity to postharvest fruits, vegetables, and grains. Twenty-nine compounds were initially screened for their activity against aphids on fava bean leaf disks. Application under reduced pressure (partial vacuum) for the first quarter of fumigation increased insecticidal activity severalfold. The 11 best aldehydes were assayed against aphids placed under the third leaf of whole heads of iceberg lettuce using the same two-tier reduced-pressure regime, which caused no additional detriment to the commodity over fumigation at atmospheric pressure. Phytotoxicity to naked and wrapped iceburg lettuce, green and red table grapes, lemon, grapefruit, orange, broccoli, avocado, cabbage, pinto bean, and rice at doses that killed 100% of aphids was recorded for three promising fumigants: propanal, (E)-2-pentenal, and 2-methyl-(E)-2-butenal. These three compounds have excellent potential as affordable postharvest insect control agents, killing 100% of the aphids with little or no detectable harm to a majority of the commodities tested. Preliminary assays indicate that similar doses are also effective against mealybugs, thrips, and whitefly.  相似文献   

Simultaneous Measurement of Local Gain and Electron Density in X-ray Lasers     

R Cauble  Da Silva LB  TW Barbee  P Celliers  C Decker  RA London  JC Moreno  JE Trebes  AS Wan  F Weber 《Science (New York, N.Y.)》1996,273(5278):1093-1096

X-ray lasers (XRLs) have experimental average gains that are significantly less than calculated values and a persistently low level of spatial coherence. An XRL has been used both as an injected signal to a short XRL amplifier and as an interferometer beam to measure two-dimensional local gain and density profiles of the XRL plasma with a resolution near 1 micrometer. The measured local gain is in agreement with atomic models but is unexpectedly spatially inhomogeneous. This inhomogeneity is responsible for the low level of spatial coherence observed and helps explain the disparity between observed and simulated gains.  相似文献   

Effective and convenient water management by tele-metering and controlling check gates in main open canal     

Kubo  Naritaka 《Paddy and Water Environment》2019,17(2):109-120

Paddy and Water Environment - Check gates being installed in a main open canal work to maintain water at a constant level in order to ensure water distribution to secondary...  相似文献   

Catalytic graphitization of hardwood acetic acid lignin with nickel acetate   总被引：1，自引：0，他引：1  

S.?Kubo  Y.?UrakiEmail author  Y.?Sano 《Journal of Wood Science》2003,49(2):188-192

 Catalytic graphitization of hardwood acetic acid lignin (HAL) with nickel (II) acetate was investigated regarding the production of highly crystalline carbon. Fusibility, one of the unique characteristics of HAL, was preserved with nickel acetate additions up to 0.3% (as the weight of nickel), although the thermal mobility of HAL was depressed by the addition of nickel acetate. An obvious effect of nickel salt as a catalyst on the development of carbon crystallite from HAL was observed for more than 0.2% addition. The development was found to proceed above 850°C. All the resulting carbons had turbostratic structure, and the apparent crystallite size (L _c) was increased with increasing amounts of catalyst, as determined by X-ray diffraction. Thus, highly crystalline carbon was produced from HAL by catalytic graphitization without compromising the fusibility of HAL by adding a small amount of organic nickel salt. Received: December 17, 2001 / Accepted: March 27, 2002 Present address: Department of Wood and Paper Science, North Carolina State University, NC 27695-8005, USA Part of this paper was presented at the 50th Annual Meeting of the Japan Wood Research Society, Kyoto, April 2000 Correspondence to:Y. Uraki  相似文献   

Analysis of boron in wood treated with boric acid solutions using Doppler broadening method of prompt gamma-rays     

Shigeru Yamauchi  Yoichi Sakai  Yasuo Watanabe  Michael Kenya Kubo  Hideaki Matsue 《Journal of Wood Science》2006,52(3):279-281

  相似文献   

ent-Isopimarane diterpenoids of the leaves from Rabdosia forrestii     

Kubo I  Shimizu K  Xu YL 《Fitoterapia》2003,74(7-8):643-649

Two new diterpenes, forrestin H, ent-isopimaran-8 beta, 15R, 16-triol (1), forrestin I, ent-isopimaran-16-acetoxy-8 beta, 15R-diol (2) and the acetonide derivative of forrestin H were isolated from the leaves of Rabdosia forrestii. The structures were established on the basis of NMR spectroscopic analysis and of the modified Mosher's (1H) method.  相似文献   

Preparation of activated carbon fibers with large specific surface area from softwood acetic acid lignin   总被引：3，自引：0，他引：3  

Yasumitsu Uraki  Akira Nakatani  Satoshi Kubo  Yoshihiro Sano 《Journal of Wood Science》2001,47(6):465-469

Softwood acetic acid lignin (SAL) free from a high-molecular-mass fraction could be spun at 220°C by a spinning machine equipped with an extruder. Although the resulting fibers required thermostabilization, this step could be conducted with a faster heating rate than that for fibers obtained from hardwood acetic acid lignin (HAL). The thermostabilized SAL fibers were converted to activated carbon fibers (ACF) by carbonization in a stream of nitrogen at 1000°C, followed by steam activation at 900°C. At an activation time of 40 min, the SAL-ACF had a larger specific surface area than the corresponding HAL-ACF. When the activation time for SAL carbon fibers was prolonged to 80 min, the adsorption capacities of resulting ACF against iodine and methylene blue were markedly increased, as was the surface area of the ACF. It was found that SAL-ACF had adsorption properties comparable to those of high-performance commercial ACF. Also, it had a tensile strength equal to that of a pitch-derived ACF.Part of this work was presented at the 49th Annual Meeting of the Japan Wood Research Society, Tokyo, April 1999  相似文献   

Maquiladora Employment Dynamics in Nuevo Laredo     

JESÚS CA AS  THOMAS M. FULLERTON  WM. DOYLE SMITH 《Growth and change》2007,38(1):23-38

ABSTRACT The Nuevo Laredo maquiladora sector has grown enormously during the last two decades. The short‐term time series characteristics of this portion of the regional economy are analyzed in an attempt to quantify the trends underlying this remarkable performance. Parameter estimation is accomplished via linear transfer function (LTF) analysis. Data are drawn from the January 1990–December 2000 sample period. Empirical results indicate that real wage rates, maquiladora plants, U.S. industrial activity, and the real exchange rate of the peso play significant roles in determining month‐to‐month fluctuations in maquiladora employment. Furthermore, sub‐sample forecast simulation exercises are conducted as an additional means for verifying model reliability. Empirical results indicate that the forecasts generated with the LTF model are less accurate than those associated with a simple random walk procedure for twelve separate step‐length periods.  相似文献   

Activated carbon sheet prepared from softwood acetic acid lignin     

Yasumitsu Uraki  Ryo Taniwatashi  Satoshi Kubo  Yoshihiro Sano 《Journal of Wood Science》2000,46(1):52-58

As an example of activated carbon (AC) moldings, AC sheets were prepared from thermoplastic acetic acid lignin by lamination. The resulting AC sheets are a new type of product that can be applied as water and air cleaners. Powdered softwood acetic acid lignin (SAL) was molded into sheets by a thermal pressing method. When the sheet was carbonized under a stream of nitrogen at 1000°C, it was deformed with expansion and contained much foam. The deformation during carbonization was suppressed by the addition of pulp to the lignin. A sheet prepared by mixing lignin with pulp was directly carbonized without thermostabilization. The carbonized sheet was activated with steam for 2h. The resulting AC sheet had adsorption properties, such as specific surface and iodine adsorption capacity, comparable to those of commercial AC powders or granules. Furthermore, the AC sheet had a larger capacity to adsorb methane than did the commercial AC powder. Therefore, SAL seems to be a promising source for the AC moldings.  相似文献