首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   9篇
  免费   0篇
化学   2篇
数学   1篇
物理学   6篇
  2022年   1篇
  2017年   1篇
  2011年   1篇
  2008年   1篇
  2006年   1篇
  2003年   3篇
  2000年   1篇
排序方式: 共有9条查询结果,搜索用时 15 毫秒
1
1.
Emerging pharmaceutical ingredients (APIs) like sulfamethoxazole (SMX), metronidazole (MNZ) and ciprofloxacin (CIP) are biopersistent and toxic to the environment and public health. In this study, UV/TiO2 photodegradation was applied in the degradation of SMX, MNZ and CIP individually and in a mixture. For a 5 mg/L SMX solution, about 97% of SMX was degraded within 360 min, which was reduced to 80% for 80 mg/L of SMX solution at the same TiO2 dosage and photodegradation time. The maximum removals of MNZ and CIP as individual components were 100% and 89%, respectively at 600 min of photodegradation reaction time. For binary mixtures, the highest removal (100%) was achieved for MNZ and CIP ([MNZ] = [CIP] = 40 mg/L) mixture at 120 min whereas the degradations were 97% and 96% for SMX and MNZ, and SMX and CIP binary mixtures, respectively, even after 600 min of experimental time at the same concentrations. For tertiary mixture, the maximum degradation 99% was observed for (SMX = CIP] = 20 mg/L and [MNZ] = [40 mg/L) at 600 min. The observed reaction rate was 0.01085 min?1 when SMX concentration was 5 mg/L, which decreased to 0.00501 min?1 for SMX concentration of 80 mg/L, indicating decreasing of reaction rate at higher concentration. The results indicate that the UV/TiO2 process is promising to apply for the treatment of pharmaceutical wastewaters.  相似文献   
2.
An ideal J of subsets of a Polish space X has (LK) property whenever for every sequence (An) of analytic sets in X, if lim supnHAnJ for each infinite H then ?nGJ for some infinite G. In this note we present a new class of σ-ideals with (LK) property.  相似文献   
3.
The process of designing an efficient tracker for thermal infrared imagery is one of the most challenging tasks in computer vision. Although a lot of advancement has been achieved in RGB videos over the decades, textureless and colorless properties of objects in thermal imagery pose hard constraints in the design of an efficient tracker. Tracking of an object using a single feature or a technique often fails to achieve greater accuracy. Here, we propose an effective method to track an object in infrared imagery based on a combination of discriminative and generative approaches. The discriminative technique makes use of two complementary methods such as kernelized correlation filter with spatial feature and AdaBoost classifier with pixel intesity features to operate in parallel. After obtaining optimized locations through discriminative approaches, the generative technique is applied to determine the best target location using a linear search method. Unlike the baseline algorithms, the proposed method estimates the scale of the target by Lucas-Kanade homography estimation. To evaluate the proposed method, extensive experiments are conducted on 17 challenging infrared image sequences obtained from LTIR dataset and a significant improvement of mean distance precision and mean overlap precision is accomplished as compared with the existing trackers. Further, a quantitative and qualitative assessment of the proposed approach with the state-of-the-art trackers is illustrated to clearly demonstrate an overall increase in performance.  相似文献   
4.
Recent experimental work on the quantized Hall state at total filling factor νT=1 in bilayer 2D electron systems has revealed a number of striking phenomena, including a giant and sharply resonant enhancement of the interlayer tunneling conductance at zero bias. The tunneling enhancement is a compelling indicator of spontaneous interlayer phase coherence among the electrons in the system. Such phase coherence is perhaps the single most important attribute of the excitonic Bose condensate which describes this remarkable quantum Hall state.  相似文献   
5.
We review the results of an extensive study of the novel luminescence rings found in GaAs and InGaAs double quantum well structures. We propose that the rings define the edge of a metastable population of carriers between the laser excitation spot and the ring. This population carries wavelike excitations at supersonic speeds. Evidence for and against associating this effect with excitonic superfluidity is reviewed. The effect cannot be easily understood in terms of a Kosterlitz-Thouless transition to a superfluid state. We examine the effects of free carriers in the system and suggest a possible mechanism for the luminescence ring effect.  相似文献   
6.
We analyze both the spatial as well as the temporal coherence of an electron-hole condensate and the radiation emitted from it. These coherences evolve from being full for the low density Bose-Einstein condensate to a chaotic behavior for a high density Bardeen-Cooper-Schrieffer-like state. Time coherence is transferred, to the emitted radiation in the ultrafast regime, in a damped oscillatory way.  相似文献   
7.
The modifications in electrical and magnetic properties of polycrystalline bulk La0.7Ca0.3Mn1−xTxO3 (T=Fe, Ga) samples at relatively higher doping concentration (x=0.08-0.12) are investigated. All the synthesized, single phase samples were subjected to resistivity measurements in the temperature range 50-300 K. No insulator-metal transition (TP) was observed for Fe doped samples with x=0.12. For all the other samples the transition temperature decreased with increase in doping concentration. The small polaron hoping energy was found to increase, rather slowly, with increase in doping concentration. The effect on magnetic properties is also prominently observed with respect to doping element and doping concentration. Interestingly, with the increase in doping concentration, the Curie temperature (TC) and TP separate out significantly indicating decoupling of electric and magnetic properties. Changes in these properties have been analyzed on the basis of magnetic disorder introduced in the system due to the magnetic and nonmagnetic nature of these ions rather than strong lattice effects which is insignificant due to similar ionic radii of Fe+3 and Ga+3 when compared to that of Mn+3.  相似文献   
8.
The biomechanical behavior of the uniting interface between the allograft bone and the autogenetic bone plays an important role in the treatment of the proximal femur massive defects with artificial tumor arthrosis/allograft prosthetic composite (TAAPC). According to the CT data of a patient, a 3D medical treatment model of TAAPC was established. Under the loads of 1.5 and 2.5 times standard body weight (70 kg), the mechanical behavior of the treatment model was analyzed by finite element analysis (FEA) for three typical healing periods. The results show that there are significant differences in the stress values and distribution in different healing periods. With healing of osteotomy, the hardness of the tissue of the uniting interface increases, the stress in uniting area was increased greatly and the stress concentration decreased. After cured the stress almost reached the level of normal bone. In the initial stage of healing, the healing training is not encouraged because there is an obvious risk of fracture of prosthesis and bone cement. In addition, porous hydroxyapatite (HA) ceramic used as bone tissue scaffold for this case, not only facilitates the generation of new bone, but also can avoid this risk caused by the non-uniting interface.  相似文献   
9.
We investigated the role of protein phosphorylation in the action of anti-L on low potassium (LK) sheep red cells. Anti-L stimulated the Na/K pump by four- to fivefold, but Na/K pump activity in anti-L-stimulated or in control cells was unaffected by protein kinase/protein phosphatase (PK/PP) inhibitors. KCl co-transport activity was inhibited by anti-L (about 50%). Co-transport was stimulated by staurosporine; and inhibited by calyculin A, okadaic acid, tyrphostin B46 and genistein; with a similar pattem in both control and anti-L-treated cells. O2 sensitivity of KCl co-transport was similar in control and anti-L-treated cells. Neither control nor anti-L-stimulated Na/K pump activities were O2 sensitive. Incubation with urea stimulated KCl co-transport in both control and anti-L-treated cells. Inhibition of co-transport by anti-L was unaffected by low concentrations of urea but was reduced at higher urea concentrations. Na/K pump activity of control cells was unaffected by incubation with urea, but that in cells stimulated by anti-L was reduced, though not significantly. Under high hydrostatic pressure, KCl co-transport was stimulated, and the inhibitory effects of PP inhibition (okadaic acid), anti-L or combinations of the two were reduced. Results suggest that anti-L does not affect K+ transport in LK sheep red cells via protein phosphorylation.  相似文献   
1
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号