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991.
师同顺 《光谱学与光谱分析》1998,18(3):293-297
研究了香兰素对甲苯胺希夫碱及其金属配合物在3800-200 cm^-1范围的傅里叶变换红外光谱光谱,对主要谱带进行了经验归属。 相似文献
992.
给出了一种单通道光学相关实现击中与否运算的算法和光学装置,此法基于形态学中的腐蚀运算和光学相关的关系及阈值操作,在非相干光学相关器中,将前景结构核元素编码为1,背景结构核元素编码为a(a满足一定条件),只需用原图像与前景和背景结构进行相关,然后对相关结果取阈值的K(前景结构核元素的像素数)即可得到击中与否运算,击中与否运算可以光学并行一步实现。 相似文献
993.
994.
995.
Magnetic properties of several potential rocksalt half-metallic ferromagnets based on the first-principles calculations 下载免费PDF全文
Several rocksalt Sr4X3N (X=,O, S, Se, and Te) are predicted to be potential half-metallic ferromagnets free of transition-metal and rare-earth elements by performing the first-principles calculations. Then their magnetic properties, such as the half metallicity and the crystal-cell magnetic moments are investigated. The Sr4X3N possibly have higher Curie temperatures and have more stable half metallicity than the Sr4X3C. Their crystal-cell magnetic moments are all 1.00 μB. The crystal-cell magnetic moments and the half metallicity arise mainly from the N ions. The main mechanism is the strong covalent interaction leading to the sp2 hybridized orbitals in the Sr4X3N. Then two Sr-5s and three N-2p electrons enter into three sp2 hybridized orbitals. Among these five electrons, four electrons are paired and one is unpaired, so there are three spin-up electrons and two spin-down electrons in these sp2 hybridized orbitals. 相似文献
996.
997.
In this work, the degradation of dimethoate solution in ultrasonic airlift loop reactor (UALR) assisted with advanced oxidation processes was studied. The effects of O3 flow rate, ultrasonic intensity, pH value and reaction temperature on the degradation rate were investigated. UALR imposed a synergistic effect combining sonochemical merit with high O3 transfer rate. Under the optimal operation conditions: ultrasonic irradiation time was 4 h, O3 flow rate was 0.41 m3 h−1, ultrasonic intensity was 4.64 W cm−2, pH value was 10.0, reaction temperature was 25 °C, and initial concentration of dimethoate was 20 mg L−1, degradation rate of dimethoate increased to 90.8%. The experimental results indicated that the method of UALR degradation of organic pollutants in the presence of gas could reduce reaction time and improve degradation rate. UALR was an advisable choice for treating organic waste waters and this device could be easily scale up. Thus this process has wide application prospect in industry. 相似文献
998.
Yao-Bei Liu Hong-Mei Han Xue-Lei Wang 《The European Physical Journal C - Particles and Fields》2008,53(4):615-620
The left–right twin Higgs (LRTH) model predicts the existence of a pair of charged Higgs bosons φ±. In this paper, we study the production of the charged Higgs boson pair φ± at the international linear collider (ILC) and the CERN large hadron collider (LHC). The numerical results show that the
production rates are at the level of several tens fb at the ILC, and the process e+e-→φ+φ- can produce adequately distinct multi-jet final states. We also discuss the charged Higgs boson pair production via the process
qq̄→φ+φ- at the LHC and estimate in this case the production rates. We find that, as long as the charged Higgs bosons are not too
heavy, they can be abundantly produced at the LHC. The possible signatures of these new particles might be detected at the
ILC and LHC experiments.
PACS 12.60.Fr; 14.80.Mz; 14.65.Ha; 12.15.Lk 相似文献
999.
The silver chromate self-assembly necklace structures were synthesized using high-active acrylicamide template. The whole
length of the necklace structure was between 1.2 and 1.5 μm. The product was composed of single crystalline nanorods with
diameters of about 40 nm and lengths of 300 nm. The synthetic mechanism and product’s optical properties were also studied. 相似文献
1000.
Tao Xu Jinghui Yang Jiwei Liu Qiang Fu 《Applied Physics A: Materials Science & Processing》2008,90(3):431-435
Grafting of fluoropolymer onto multi-walled carbon nanotube (MWCNTs) powder by CF4 plasma treatment was investigated in this study. In order to achieve a uniform treatment of powder, a rotating barrel was
designed and fixed between the two discharge electrodes. The influence of various plasma parameters, such as power and treatment
time, on the fluorination of MWCNT surface was systematically analyzed by X-ray photoelectron spectroscopy (XPS), Fourier
transformed infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The results revealed that a successful fluorination
of MWCNT powder with a maximum of fluorine content of 12% could be achieved by using our plasma equipment. Our work provides
a new way for the homogeneous fluorination of MWCNT powder and is valuable for industrial production.
PACS 52.50.Dg; 52.40.Mj; 52.59. Ye; 52.77.-j 相似文献