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排序方式: 共有1292条查询结果,搜索用时 15 毫秒
31.
Lili Hao Wangyu Hu Chuan Wang Guangzong Wang Yue Sun Jun Chen Xueping Pan 《全球能源互联网(英文)》2023,(2):205-227
In an integrated energy system(IES) composed of multiple subsystems, energy coupling causes an energy supply blockage or shutdown in one subsystem, thereby affecting the energy flow distribution optimization of other subsystems.The energy supply should be globally optimized during the IES energy supply restoration process to produce the highest restoration net income. Mobile emergency sources can be quickly and flexibly connected to supply energy after an energy outage to ensure a reliable suppl... 相似文献
32.
Polarizing beam splitter has rather significant applications in polarization diversity circuits and polarization multiplexing systems. In this paper,we present an asymmetric polarizing beam splitter utilizing hybrid plasmonic waveguide. The special hybrid structure with a hybrid waveguide and a dielectric waveguide can limit the energy of TE and TM modes to a different layer. Therefore, we can achieve beam splitting by adjusting the corresponding parameters of the two waveguides. First, we studi... 相似文献
33.
Yan-Yan Ding Yang-Bo Nie Yue Zhang Zhi-Jie Hu Qi Zhao Huan-Yu Zhang Kuo-Zhi Xu Shi-Yu Zhang Xin-Yi Pan Chang-Lin Lan Jie Ren Xi-Chao Ruan 《核技术(英文版)》2024,(2):123-137
A benchmark experiment on 238U slab samples was conducted using a deuterium–tritium neutron source at the China Institute of Atomic Energy. The leakage neutron spectra within energy levels of 0.8–16 MeV at 60° and 120° were measured using the time-of-flight method. The samples were prepared as rectangular slabs with a 30 cm square base and thicknesses of 3,6, and 9 cm. The leakage neutron spectra were also calculated using the MCNP-4C program based on the latest evaluated files of 相似文献
34.
Tingting Peng Yangyan Chen Wanshan Hu Yao Huang Minmin Zhang Chao Lu Xin Pan Chuanbin Wu 《工程(英文)》2023,(11):170-189
Microneedles(MNs) can be used for the topical treatment of skin disorders as they directly deliver therapeutics to the site of skin lesions, resulting in increased therapeutic efficacy while having minimum side effects. MNs are used to deliver different kinds of therapeutics(e.g., small molecules, macromolecules,nanomedicines, living cells, bacteria, and exosomes) for treating various skin disorders, including superficial tumors, wounds, skin infections, inflammatory skin diseases, and abnormal ... 相似文献
35.
Structural control and element doping are two popular strategies to produce semiconductors with surface enhanced Raman spectroscopy(SERS) properties. For TiO_2 based SERS substrates, maintaining a good crystallinity is critical to achieve excellent Raman scattering. At elevated temperatures(N600 °C), the phase transition from anatase to rutile TiO_2 could result in a poor SERS performance. In this work, we report the successful synthesis of TiO_2 nanowhiskers with excellent SERS properties. The enhancement factor, an index of SERS performance, is 4.96 × 10~6 for methylene blue molecule detecting, with a detection sensitivity around 10~(-7) mol·L~(-1).Characterizations, such as XRD, Raman, TEM, UV–vis and Zeta potential measurement, have been performed to decrypt structural and chemical characteristics of the newly synthesized TiO_2 nanowhiskers. The photo absorption onset of MB adsorbed TiO_2 nanowhiskers was similar to that of bare TiO_2 nanowhiskers. In addition, no new band was observed from the UV–vis of MB modified TiO_2 nanowhiskers. Both results suggest that the high enhancement factor cannot be explained by the charge-transfer mechanism. With the support of ab initio density functional theory calculations, we reveal that interfacial potassium is critical to maintain thermal stability of the anatase phase up to 900 °C. In addition, the deposition of potassium results in a negatively charged TiO_2 nanowhisker surface, which favors specific adsorption of methylene blue molecules and significantly improves SERS performance via the electrostatic adsorption effect. 相似文献
36.
Mixed strains Delftia sp.YH01 and Acidovorax sp.YH02, with capability of heterotrophic nitrification-aerobic denitrification, were introduced into a two-stage aerobic sequencing batch reactor to enhance NO3−-N removal. With optimal C/N of 8, efficient NO3−-N removal was achieved at initial NO3−-N concentration of 2000 mg·L−1. Meanwhile, the massive accumulation of NO2−-N was avoided during the long operation. Compared to the one-stage aerobic sequencing batch reactor, the removal efficiency of NO3−-N and TN in the two-stage aerobic sequencing batch reactor was increased by 36.5% and 42.7%, which respectively was 93.8% and 88.4%. Microbial community study showed that the mixed strains have the stronger viability and can synergistically denitrify with the indigenous microorganisms in system, such as Azoarcus, Uncultured Saprospiraceae, Thauera, Paracocccus, which could be major contributors for aerobic denitrification. The proposed technology was shown to achieve high-efficiency treatment of high NO3−-N wastewater through aerobic denitrification. 相似文献
37.
纳米级SiO2改性水泥胶砂作用机理研究 总被引:2,自引:0,他引:2
用XRD、TGA-DTA分析了纳米级SiO2改性水泥砂浆后的水泥基材料的性能变化,探索了纳米级SiO2的改性机理。XRD、TGA-DTA分析表明水泥砂浆被改性后,Ca(OH)2晶体取向程度降低,晶粒细化且呈无定型。改性后水化产物增多,导致强度增大。除了进行微观力学性能测试之外,用SEM测试评价了纳米级SiO2改性水泥砂浆后的微观形貌,发现在水泥基中添加纳米级SiO2能使水化速率增快,水化产物增多,龄期结构变得致密,导致强度增大,耐久性提高。 相似文献
38.
Wu JC Lai CS Badmaev V Nagabhushanam K Ho CT Pan MH 《Molecular nutrition & food research》2011,55(11):1646-1654
Scope: Autophagy (type II programmed cell death) is crucial for maintaining cellular homeostasis. Several autophagy‐deficient or knockout studies indicate that autophagy is a tumor suppressor. Tetrahydrocurcumin (THC), a major metabolite of curcumin, has been demonstrated with anti‐colon carcinogenesis and antioxidation in vivo. Methods and results: In the present study, we found that treatment with THC induced autophagic cell death in human HL‐60 promyelocytic leukemia cells by increasing autophage marker acidic vascular organelle (AVO) formation. Flow cytometry also confirmed that THC treatment did not increase sub‐G1 cell population whereas curcumin did with strong apoptosis‐inducing activity. At the molecular levels, the results from Western blot analysis showed that THC significantly down‐regulated phosphatidylinositol 3‐kinase/protein kinase B and mitogen‐activated protein kinase signalings including decreasing the phosphorylation of mammalian target of rapamycin, glycogen synthase kinase 3β and p70 ribosomal protein S6 kinase. Further molecular analysis exhibited that the pretreatment of 3‐methyladenine (an autophagy inhibitor) also significantly reduced acidic vascular organelle production in THC‐treated cells. Conclusion: Taken together, these results demonstrated the anticancer efficacy of THC by inducing autophagy as well as provided a potential application for the prevention of human leukemia. 相似文献
39.
Lin QB Zhao XT Song H Pan YL 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2012,29(6):935-941
A highly selective and sensitive method was developed for the simultaneous determination of four β-agonists (clenbuterol, salbutamol, ractopamine and terbutaline) in beef by immunoaffinity chromatography purification coupled to ultra-high-performance LC-MS/MS. The MS/MS conditions, ultra-high-performance LC mobile phase, injection solution, sample purification process and matrix effect were studied to optimise the operation conditions. The limits of detection (LODs) of the instrument for the studied β-agonists ranged from 0.20 to 0.25 μg l(-1), and the LODs of the method for the studied β-agonists ranged from 0.20 to 3.00 μg kg(-1) for beef. Calibration curves were constructed using a standard solution diluted with blank beef matrix. The linear ranges of the calibration curves ranged from 5 to 100 μg kg(-1) and the coefficients of determination were >0.9942 (n = 10) for all four β-agonists. Samples spiked at 5, 10 and 50 μg kg(-1) showed recoveries >72% and RSDs <6.6%. The method is suitable for the simultaneous detection of four β-agonists at trace levels in beef. 相似文献
40.
Qiu P Guan H Dong P Li S Ho CT Pan MH McClements DJ Xiao H 《Molecular nutrition & food research》2011,55(4):613-622
Scope: Previously, we reported that 5‐hydroxy polymethoxyflavones (5OH‐PMFs) isolated from orange, namely 5‐hydroxy‐6,7,8,3′,4′‐pentamethoxyflavone, 5‐hydroxy‐3,6,7,8,3′,4′‐hexamethoxyflavone (5HHMF) and 5‐hydroxy‐6,7,8,4′‐tetramethoxyflavone (5HTMF), potently induced apoptosis and cell‐cycle arrest in multiple human colon cancer cells. Herein, using isogenic variants of HCT116 human colon cancer cells, we investigated the effects of p53, Bax and p21 on the apoptosis and cell‐cycle arrest induced by different 5OH‐PMFs. Methods and results: Annexin V/PI co‐staining assay demonstrated that 5HHMF and 5HTMF significantly induced apoptosis in HCT116 (p53+/+) cells but not in HCT116 (p53?/?) cells. Furthermore, 5HHMF and 5HTMF significantly induced apoptosis in HCT116 (Bax+/?) cells, whereas their pro‐apoptotic effects on HCT116 (Bax?/?) cells were marginal. All three 5OH‐PMFs increased G0/G1 cell population of HCT116 (p53+/+) cells, and these effects were abolished in HCT116 (p53?/?) and HCT116 (p21?/?) cells. Immunoblotting analysis showed that 5HHMF and 5HTMF increased the levels of cleaved caspase‐3, cleaved PARP in both HCT116 (p53+/+) and HCT116 (Bax+/?) cells and these effects were much weaker in HCT116 (p53?/?) and HCT116 (Bax?/?) cells. Conclusion: Our results demonstrated that 5OH‐PMFs, especially 5HHMF and 5HTMF, induce apoptosis and cell‐cycle arrest by p53‐, Bax‐ and p21‐dependent mechanism. 相似文献