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排序方式: 共有239条查询结果,搜索用时 46 毫秒
71.
Alaa Eldin M. A. Morshdy Ahmed S. El-tahlawy Sameer H. Qari Alaa T. Qumsani Daniyah Habiballah Bay Rokayya Sami Eman Hillal Althubaiti Ahmed M. A. Mansour Amani H. Aljahani Abd El-Salam E. Hafez Abdallah Fikry A. Mahmoud Rasha M. El Bayomi Mohamed A. Hussein 《Molecules (Basel, Switzerland)》2022,27(7)
Biofilm control by essential oil (EO) application has recently increased to preclude biofilm production on foods and environmental surfaces. In this work, the anti-biofilm effects of garlic and thyme essential oils using the minimum inhibitory concentration (MIC) method against Salmonella typhimurium recovered from different abattoir samples were investigated along with the virulence genes (InvA, SdiA and Stn genes), and the antimicrobial susceptibility profile of S. typhimurium as well. The obtained results revealed that S. typhimurium contaminated abattoir samples to varying degrees. The InvA gene was investigated in all isolates, whereas the SdiA and Stn genes were observed in four and three isolates, respectively. Utilizing the disc diffusion method, S. typhimurium isolates demonstrated substantial resistance to most of the examined antibiotics with a high multiple antibiotic resistance index. S. typhimurium isolates demonstrated biofilm formation abilities to various degrees at varied temperatures levels (4 °C and 37 °C). In conclusion, the obtained samples from the research area are regarded as a potential S. typhimurium contamination source. Furthermore, garlic essential oil (GEO) has more potential to inhibit S. typhimurium biofilm at different sub-minimum inhibitory concentrations as compared to thyme essential oil (TEO). Therefore, these EOs are considered as potential natural antibacterial options that could be applied in food industry. 相似文献
72.
73.
Zeitschrift für Physik A Hadrons and nuclei - Es wurde eine neue Methode zur Untersuchung der Streuung von γ-Strahlen entwickelt. Mit dieser Anordnung wurde die Intensitätsverteilung... 相似文献
74.
75.
H. Hardtdegen R. Steins N. Kaluza Y.S. Cho K. Wirtz M. von der Ahe H.L. Bay G. Heidelberger M. Marso 《Applied Physics A: Materials Science & Processing》2007,87(3):491-498
This paper reports on new approaches for growth control of GaN-based heterostructures for high frequency and high power application.
First in situ methods are presented and their further development discussed [1]. The development leads to a greatly improved
observation of growth parameter influences in the MOVPE of GaN. A new growth process is introduced which enhances growth reproducibility
[2]. This new growth process is then optimized with respect to the envisaged application. To this end process modeling will
be employed. The application envisaged is the AlxGa1-xN/GaN high electron mobility transistor (HEMT). At last device results will be presented. All in all it will be shown how
fundamental research can drive technology and how basic knowledge can be employed for process development with respect to
device applications.
PACS 68.35.Ct; 68.55.Ac; 78.66.Fd; 81.15.Kk 相似文献
76.
In this study, we consider a segmented market for a product that can either be manufactured or remanufactured. It is assumed that the remanufactured products can be substituted by the new ones. A steady-state profit model is constructed under certain environmental assumptions on capacity requirements of operations, and revenue and cost schemes. Exact steady-state probabilities of the Markovian model constructed are solved via matrix geometric techniques. An extensive computational study is performed to investigate the conditions under which the utilization of remanufacturing option and the use of one-way substitution policy increase the average expected profit. 相似文献
77.
The metastable a(1)[(3)Sigma(+)] state of PbO has been suggested as a suitable system in which to search for the electric dipole moment of the electron. We report here the development of experimental techniques allowing high-sensitivity measurements of Zeeman and Stark effects in this system, similar to those required for such a search. We observe Zeeman quantum beats in fluorescence from a vapor cell of PbO, with shot-noise limited extraction of the quantum beat frequencies, high counting rates, and long coherence times. We argue that improvement in sensitivity to the electron electric dipole moment by at least 2 orders of magnitude appears possible using these techniques. 相似文献
78.
Wang MZ Lee YJ Abe K Abe K Abe T Aihara H Akatsu M Asano Y Aso T Aushev T Bakich AM Ban Y Banas E Bay A Behera PK Bizjak I Bondar A Bozek A Bracko M Browder TE Casey BC Chang MC Chang P Chao Y Chen KF Cheon BG Chistov R Choi Y Choi YK Drutskoy A Eidelman S Eiges V Fukunaga C Gabyshev N Garmash A Gershon T Golob B Guo R Hagner C Hara T Hazumi M Hojo T Hokuue T Hoshi Y Hou WS Hsiung YB Huang HC Igaki T Igarashi Y Iijima T Inami K Ishikawa A Itoh R Iwasaki H Iwasaki Y Jang HK Kang JH Kang JS 《Physical review letters》2003,90(20):201802
We report the first observation of the charmless hyperonic B decay, B0-->pLambda(pi)(-), using a 78 fb(-1) data sample recorded on the Upsilon(4S) resonance with the Belle detector at KEKB. The measured branching fraction is B(B0-->pLambda(pi)(-))=(3.97(+1.00)(-0.80)+/-0.56)x10(-6). Searches for B0-->pLambda(K)- and pSigma(0)pi(-) yield no significant signals and we set 90% confidence-level upper limits of B(B0-->pLambda(K)-)<8.2x10(-7) and B(B0-->pSigma(0)pi(-))<3.8x10(-6). 相似文献
79.
Abe K Adachi I Aihara H Asano Y Aulchenko V Aushev T Bakich AM Balagura V Banerjee S Barberio E Barbero M Bay A Bedny I Bitenc U Bizjak I Blyth S Bondar A Bozek A Bracko M Brodzicka J Browder TE Chang P Chao Y Chen A Chen KF Chen WT Cheon BG Chistov R Choi SK Choi Y Chuvikov A Cole S Dalseno J Danilov M Dash M Dong LY Dragic J Drutskoy A Eidelman S Enari Y Fratina S Gabyshev N Gershon T Go A Gokhroo G Golob B Gorisek A Haba J Hara T Hastings NC Hayasaka K Hayashii H Hazumi M Hinz L Hokuue T 《Physical review letters》2005,95(23):231802
We report measurements of B meson decays to two kaons using 253 fb(-1) of data collected with the Belle detector at the KEKB energy-asymmetric e+ e- collider. We find evidence for signals in B+ --> K0 K+ and B0 --> K0 K0 with significances of 3.0sigma and 3.5sigma, respectively. (Charge-conjugate modes are included.) The corresponding branching fractions are measured to be [symbol: see text](B+ --> K0 K+) = (1.0 +/- 0.4 +/- 0.1) x 10(-6) and [symbol: see text](B0 --> K0 K0) = (0.8 +/- 0.3 +/- 0.1) x 10(-6). These decay modes are examples of hadronic bd transitions. No signal is observed in the decay B0 --> K+ K-, and we set an upper limit of 3.7 x 10(-7) at 90% confidence level. 相似文献
80.
The sputtering yield of Ni, Mo, and Au have been measured at oblique angles of incidence for H+-, D+-, and4He+-ion irradiation in the energy region from 1 to 8 keV. The yields were determined from the weight loss of the targets. For
Ni and Mo the dependence of the sputtering yield on the angle of incidence was found to be much stronger for H+- and D+-ion than for4He+-ion irradiation. In all cases the maximum in the yield was found at angles of incidence ϑ≧80°, where ϑ is the angle measured
from the surface normal. Furthermore the ratio of the maximum yield to the yeild at normal incidence increases with increasing
surface binding energy of the target material as well as with increasing ion energy in the energy region inveestigated. The
results are discussed qualitatively in view of a model for the sputtering mechanism for light ions. 相似文献