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排序方式: 共有182条查询结果,搜索用时 15 毫秒
1.
分别采用功率密度为1.7W/cm2、照射剂量为2000J/cm2的Ar+激光与LD激光辐照高耐药性的志贺氏福氏痢疾杆菌,波长较短的Ar+激光(488nm)所引起细菌的致死率与药敏实变率明显高于波长较长的LD激光(808nm),即波长较短的Ar+激光的辐照导致细菌耐药性显著降低. 相似文献
2.
Esteso Ana Alemany M. M. E. Ortiz Angel Liu Shaofeng 《Central European Journal of Operations Research》2022,30(3):1101-1127
Central European Journal of Operations Research - Agri-food production must increase while food waste needs to be reduced for improving the position of farmers. To do so it is necessary to... 相似文献
3.
近年来,中草药有效成分的研究引起国内外有关学者普遍关注。氚标记中草药有效成分是研究其相应的药代动力学和代谢产物的主要手段,它具有操作简便,条件温和等优点,但是一般氚化方法均不能明确给出氚化位置。而研究氚化定位效应又是药理工作者急待解决的重要课题,所以在很大程度上限制了该项技术的使用范围。最近,郑冬珠等人用FX—100型核磁共振谱仪给出了在PdO催化剂存在条件下,低压氚化亮石松碱的氚化位置及其相对含量。本文在前文基础上,以亮石松碱为底物,根据Fraser和Garnett等人提出的氢—氚同位素交换反应动力学理论,采用CNDO/2法,对PdO催化亮石松碱的立体构型讲行了计算,得出一些有意义的结果。 相似文献
4.
Shaofeng Zhang Yong-Seung Shin Richard Mayer Franco Basile 《Journal of Analytical and Applied Pyrolysis》2007,80(2):353-359
An on-probe pyrolyzer has been constructed and interfaced with desorption electrospray ionization (DESI) mass spectrometry (MS) for the rapid analysis of non-volatile pyrolysis products. The detection and analysis of non-volatile pyrolysis products of peptides, proteins and the synthetic polymer poly(ethylene glycol) were demonstrated with this instrument. The on-probe pyrolyzer can be operated off-line or on-line with the DESI source and was interfaced with a tandem MS (MS/MS) instrument, which allowed for structure characterization of the non-volatile pyrolytic products. Advantages of this system are its simplicity and speed of analysis since the pyrolysis is performed in situ on the DESI source probe and hence, it avoids extraction steps and/or the use of matrices (e.g., as in MALDI–MS analyses). 相似文献
5.
目的 观察并比较透明质酸钠、碱化利多卡因联合肝素膀胱灌注治疗膀胱疼痛综合征/ 间质性膀胱炎(BPS/IC)的临
床疗效。方法 将63 例BPS/IC 患者按随机单盲的原则分成A、B 两组,A 组32 例,B 组31 例。A 组患者予膀胱灌注透明质酸钠40ml;B 组予膀胱灌注碱化利多卡因联合肝素治疗,即用5%碳酸氢钠10ml、2%利多卡因10ml、肝素钠2.5 万U 和0.9%氯化钠15ml的混合液行膀胱灌注。两组均保留40~60min,每周2 次,4周后改为每周1 次,共16 次。观察两组患者用药前及用药开始后4、12周时的O’Leary-Sant平均症状评分(ICPI)、问题评分(ICSI)及生活质量评分(QOL),并记录不良反应。结果 两组患者治疗开始后4周和12 周ICPI、ICSI 及QOL评分均有明显改善,与治疗前比较均有统计学差异(均P<0.05)。治疗4 周后两组的ICPI、ICSI 及QOL 评分下降分值比较均无统计学差异(均P>0.05),但治疗12 周后A 组的ICPI、ICSI 及QOL评分下降分值较B 组更为明显(均P<0.05)。所有患者治疗过程中均未发生明显不良反应。结论 透明质酸钠及碱化利多卡因联合肝素膀胱灌注均能改善BPS/IC患者的临床症状,而透明质酸钠疗效更为显著。 相似文献
6.
Shaofeng Wang 《哲学杂志》2015,95(33):3768-3784
A fundamental equation is derived for the structure of dislocations in solids. With the interaction potential that can be obtained properly from the first principle, the equation provides a complete basis for a comprehensive study of the dislocation structure. In particular, the full structural feature and related properties of dislocation can be predicted theoretically, which makes it possible to compare precisely the theoretical results and what is produced by experiments or numerical simulations. 相似文献
7.
Development of a new method for analysis of Sudan dyes by pressurized CEC with amperometric detection 总被引:1,自引:0,他引:1
A new analytical method, pressurized CEC (pCEC) with amperometric detection (AD) using 1.5 microm RP nonporous silica packed columns has been developed for the rapid separation and determination of four Sudan dyes in hot chilli. The influence of several experimental parameters on the retention behavior has been investigated. The electrochemical oxidation of Sudans I-IV separated by pCEC can be reliably monitored with a carbon electrode at +0.95 V (vs. Ag/AgCl). Fast and efficient separation of the analytes was achieved within 7 min by pCEC under the optimum conditions with an ACN/water (95:5%) mobile phase containing formic acid (pH 4.3), 5% acetone and 0.002% triethylamine using a separation voltage of 12 kV. The detection limits for four Sudan dyes ranged from 8.0 x 10(-7) to 1.2 x 10(-6) mol/L. To evaluate the feasibility and reliability of this method, the proposed pCEC-AD method was further demonstrated with hot chilli samples spiked with Sudan dyes. 相似文献
8.
9.
Determination of the surface states from the ultrafast electronic states in a thermoelectric material
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We reveal the electronic structure in Yb Cd2Sb2,a thermoelectric material,by angle-resolved photoemission spectroscopy(ARPES)and time-resolved ARPES(tr ARPES).Specifically,three bulk bands at the vicinity of the Fermi level are evidenced near the Brillouin zone center,consistent with the density functional theory(DFT)calculation.It is interesting that the spin-unpolarized bulk bands respond unexpectedly to right-and left-handed circularly polarized probe.In addition,a hole band of surface states,which is not sensitive to the polarization of the probe beam and is not expected from the DFT calculation,is identified.We find that the non-equilibrium quasiparticle recovery rate is much smaller in the surface states than that of the bulk states.Our results demonstrate that the surface states can be distinguished from the bulk ones from a view of time scale in the nonequilibrium physics. 相似文献
10.
The dissociated core structure of dislocation in two-dimensional triangular lattice is determined by the variational method
within lattice theory. The dissociation effect leads to a narrower core width of partial dislocations than the compact one.
The equilibrium separation between two partial dislocations is not very sensitive to the intrinsic stacking fault energy and
there exists deviation from the intrinsic stacking fault energy criterion in the continuous elastic theory of dislocation.
The relationship between the equilibrium separation and intrinsic stacking fault energy is analogous in lattice theory and
the Peierls-Nabarro model. But the equilibrium separation obtained in lattice theory is wider than that obtained in the Peierls-Nabarro
model for the same intrinsic stacking fault energy.
相似文献