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1.
匀速运动的电偶极子的电场和磁场分布   总被引:4,自引:1,他引:3  
本文通过对电偶极子电磁势的分析和相对论下电磁场在不同惯性系中的协变分布,计算了作匀速直线运动的电偶极子的电场和磁场的空间分布.  相似文献   
2.
本文应用上、下解方法和 Leray-Schauder不动点定理 ,证明了一类拟线性椭圆方程边值问题弱解的存在性 ,并且给出了一个应用实例  相似文献   
3.
通过构建高密度直接蒸发式冰盘管实验台,研究了不同冰盘管密度对取冷特性的影响。实验结果表明:随着蓄冷槽中冰盘管密度的增大,可使直接蒸发式蓄冰槽取冷水温进一步降低,取冷速率进一步提高,从而能更好地满足低温送风空调系统的要求及空调高峰负荷变化的需要。  相似文献   
4.
1.INTRODUCTION[()-227.3()]Endotoxinislipopolysaccharide(LPS)derivedfromthecellmembranesofgram-negativebacteria.Endotoxincancausefebrilereactionsinanimalswithsymptomsofhighfever,vasodilation,diarrheaandfetalshockwheninjectedeveninaverysmallamount[1].Iftheconcentrationofendotoxininpatients?bloodishighenoughitcancauseseveresepsis,whichisamajorcauseofdeathinpatientsandcontinuestohaveahighmortalitydespiteappropriatesurgery,potentantibiotic,andintensivesupportivetherapy[2~5].LipidAisthemaintox…  相似文献   
5.
To find an effective extraction and removal method for palladium(II), which is one of the main fission products from an acidic nuclear spent fuel solution, the extraction behavior of palladium(II) from a nitric acid medium by an acidic chelating extractant, 1-phenyl-3-methyl-4-trifluoroacetylpyrazolone-5-one (HPMTP) and a tertiary amine of high molecular weight, tri-n-octylamine (TOA), has been studied by spectrophotometry. A noticeable antagonistic extraction effect was observed in the extraction system under the given conditions. To understand this phenomenon, a preliminary investigation was performed to explain the mechanism of this reaction. According to the theory of corresponding solutions (TCS), the association reaction between HPMTP and TOA is proposed in the organic phase. An associated species, HPMTP·TOA, formed through hydrogen bonding in a chloroform medium might be the main reason why an antagonistic extraction effect occurred. The association constant between HPMTP and TOA was calculated to be 2.86±0.05.  相似文献   
6.
In this paper, a practical structured light-based system for fast object modeling and reconstruction is reported. The system consists of an off-the-shelf digital projector, a video camera and a turntable. The system calibration is implemented accurately and automatically by taking a single image of an illuminated calibration template. The multiple color light stripes emitted by the projector adopt only three colors and the color can be modified easily according to the surface texture of the object. This makes the system widely applicable in many situations, and the assumption about color neutrality, which is a limitation to other similar systems, can be largely relaxed. The registration and merging algorithm is greatly simplified by employing a turntable. The validity and high accuracy of the method are demonstrated by extensive real experiments.  相似文献   
7.
During a comparison study of the fast atom bombardment (FAB) and electron impact mass spectra of 1-organyl-2,9,10-trioxa-6-aza-1-silatricyclo[4.3.3.01,6]dodecanes, an unusual ion peak at m/z 164 was noticed in the FAB spectra. Accurate mass measurement indicated that m/z 164 corresponds to protonated 1-[N,N-bis(2-hydroxyethyl)amino]-1-propanol (BHAP), which is produced by a ring-rupture reaction. Further experiment showed that the intensity of the [BHAP + H]+ ion peak increased markedly as the 7keV Ar0 bombardment proceeded, suggesting a FAB-induced reaction. The possible mechanism is also discussed.  相似文献   
8.
Inhibition of the glycolytic pathway is a critical strategy in anticancer therapy because of the role of aerobic glycolysis in cancer cells. The glycolytic inhibitor 2-Deoxy-d-glucose (2-DG) has shown potential in combination with other anticancer agents. Buforin IIb is an effective antimicrobial peptide (AMP) with broad-spectrum anticancer activity and selectivity. The efficacy of combination treatment with 2-DG and buforin IIb in prostate cancer remains unknown. Here, we tested the efficacy of buforin IIb as a mitochondria-targeting AMP in the androgen-independent human prostate cancer cell line DU145. Combining 2-DG with buforin IIb had a synergistic toxic effect on DU145 cells and mouse xenograft tumors. Combination treatment with 2-DG and buforin IIb caused stronger proliferation inhibition, greater G1 cell cycle arrest, and higher apoptosis than either treatment alone. Combination treatment dramatically decreased L-lactate production and intracellular ATP levels, indicating severe inhibition of glycolysis and ATP production. Flow cytometry and confocal laser scanning microscopy results indicate that 2-DG may increase buforin IIb uptake by DU145 cells, thereby increasing the mitochondria-targeting capacity of buforin IIb. This may partly explain the effect of combination treatment on enhancing buforin IIb-induced apoptosis. Consistently, 2-DG increased mitochondrial dysfunction and upregulated Bax/Bcl-2, promoting cytochrome c release to initiate procaspase 3 cleavage induced by buforin IIb. These results suggest that 2-DG sensitizes prostate cancer DU145 cells to buforin IIb. Moreover, combination treatment caused minimal hemolysis and cytotoxicity to normal WPMY-1 cells. Collectively, the current study demonstrates that dual targeting of glycolysis and mitochondria by 2-DG and buforin IIb may be an effective anticancer strategy for the treatment of some advanced prostate cancer.  相似文献   
9.
In phosphate buffer-diethylene glycol monobutyl ether(DGBE), the oxidations of ferrocene and 15 derivatives were investigated in the presence of Rhus vernicifera laccase. The results showed that ferrocene and 11 derivatives can be oxidized. The mechanism of Laccase catalyzed oxidation of ferrocene was put forward.  相似文献   
10.
Study on oxidation of polymers treated by high LET radiation   总被引:2,自引:0,他引:2  
The oxidation of medical silicone rubber and segmented polyether urethane which were bombarded with 11.2 MeV Si+ or F+ at the dose of 5 × 1014 ions/cm2 was studied. In XPS measurements, it was found that the oxygen concentration on the surface of the implanted polymeric membranes had been increasing in three months at least. ESR measurement showed that some free radicals existed in these membranes and their quantities decreased with time. Chemical analysis proved that peroxides were generated in the γ irradiated membranes. The reason for the increasing of oxygen concentration was that free radicals combined with oxygen in the air and produced peroxides on the membrane surface. Moreover, in order to demonstrate the radiation mechanism, low LET (γ rays) radiation of such polymeric membranes was carried out for comparison  相似文献   
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