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1.
1　Ｉｎｔｒｏｄｕｃｔｉｏｎ　Ｔｈｅｃｈｅｍｉｃａｌｅｆｆｅｃｔｓｏｆｕｌｔｒａｓｏｕｎｄａｒｅｄｕｅｔｏｈｉｇｈｐｒｅｓｓｕｒｅｐｒｏｄｕｃｅｄｄｕｒｉｎｇｖｉｏｌｅｎｔｃｏｌｌａｐｓｅｏｆｃａｖｉｔａｔｉｏｎｂｕｂｂｌｅｓ.Ｔｈｅｒｅａｃｔｉｏｎｓｄｏｎｏｔｔａｋｅ ｐｌａｃｅｈｏｍｏｇｅ ｎｅｏｕｓｌｙｉｎｔｈｅｓｏｌｕｔｉｏｎｂｕｔｉｎ”ｈｏｔｓｐｏｔｓ”ｗｈｅｒｅｃａｖｉ ｔａｔｉｏｎｂｕｂｂｌｅｓｐｕｌｓａｔｅｏｒｃｏｌｌａｐｓｅ .Ｄｕｒｉｎｇｔｈｅａｄｉａｂａｔ ｉｃｃｏｍｐｒｅｓｓｉｏ…  相似文献   

2.
1　Ｉｎｔｒｏｄｕｃｔｉｏｎ　Ｆｅ Ｎｉａｌｌｏｙｉｓｗｉｄｅｌｙｕｓｅｄａｓｓｏｆｔｍａｇｎｅｔｉｃｍａｔｅｒｉａｌｓｆｏｒａｌｏｎｇｔｉｍｅ .Ｉｔｓｍａｇｎｅｔｉｃｐｒｏｐｅｒｔｉｅｓａｓｉｎｉｔｉａｌｐｅｒｍｅ ａｂｉｌｉｔｙμｉａｎｄｃｏｅｒｃｉｖｉｔｙｆｏｒｃｅＨｃｄｅｐｅｎｄｓｔｒｏｎｇｌｙｏｎｔｈｅｃｈｅｍｉｃａｌｃｏｍｐｏｓｉｔｉｏｎａｎｄｔｒｅａｔｍｅｎｔｌｉｋｅｑｕｅｎｃｈｉｎｇｆｒｏｍｈｉｇｈｔｅｍｐｅｒａｔｕｒｅ .Ａｓｕｌｔｒａｆｉｎｅｐａｒｔｉｃｌｅｉｓｒｅｖｅａｌｅｄｒ…  相似文献   

3.
1　Ｉｎｔｒｏｄｕｃｔｉｏｎ　Ｏｗｉｎｇｔｏｉｔｓｈｉｇｈｈｙｄｒｏｇｅｎ ｓｔｏｒａｇｅａｂｉｌｉｔｙ ,ｌｏｗｃｏｓｔａｎｄａｂｏｕｎｄｉｎｎａｔｕｒａｌｒｅｓｏｕｒｃｅｓ ,Ｍｇ ｂａｓｅｄａｌｌｏｙｂｅ ｃｏｍｅｓａｃｏｍｐｅｔｉｔｉｖｅｈｙｄｒｏｇｅｎ ｓｔｏｒａｇｅｍｅｄｉｕｍｗｈｉｃｈｃａｎｂｅｕｓｅｄｉｎＮｉ ＭＨｂａｔｔｅｒｙａｎｄｆｕｅｌｃｅｌｌ.Ｔｈｅｅｌｅｃ ｔｒｏｃｈｅｍｉｃａｌｍｅｔｈｏｄｈａｓｂｅｅｎｕｓｅｄｉｎｔｈｅｓｔｕｄｙｏｆｈｙ ｄｒｏｇｅｎａｔｉｏｎ/ｄｅｈｙｄｒｏｇｅ…  相似文献   

4.
Ｓｅｃｔｉｏｎ1 :ＢｒｅａｋｄｏｗｎｏｆＦｏｒｃｅｓＹｏｕｃａｎｂｒｅａｋｄｏｗｎｆｏｒｃｅｓｉｎｔｏｓｅｖｅｒａｌｃｏｍｐｏｎｅｎｔｓｅａｓｌｉｌｙ.Ｆｏｒｅｘａｍｐｌｅ,ｔｈｅｆｏｒｃｅＦ1 ａｔ30ｄｅｇｒｅｅｃａｎｂｅｂｒｏ ｋｅｎｉｎｔｏｔｗｏｆｏｒｃｅｓ:ＦｘａｎｄＦｙ,ａｎｄＦｘ=ｃｏｓ30°×Ｆ1 ,Ｆｙ=ｓｉｎ30°×Ｆ1 .Ｓｅｃｔｉｏｎ2 .ＴｗｏＤｉｍｅｎｓｉｏｎａｌＦｏｒｃｅｓｉｎｔｏＯｎｅＹｏｕｃａｎｃｏｍｂｉｎｅｔｗｏｆｏｒｃｅｓｉｎｔｏｏｎｅ.ＳｕｐｐｏｓｅＴｏｍｐｕｓｈｅｄａｂｏｘｗｉｔ…  相似文献   

5.
１　Ｉｎｔｒｏｄｕｃｔｉｏｎ　Ｈ．Ｐ．Ｙｕｅｎｉｎｔｒｏｄｕｃｅｄｔｈｅｃｏｎｃｅｐｔｏｆｔｗｏｐｈｏｔｏｎｃｏｈｅｒｅｎｔｓｔａｔｅｉｎ１９７６［１］．Ｓｉｎｃｅｔｈａｔｔｉｍｅ,ｔｈｅｓｑｕｅｅｚｅｄｓｔａｔｅｓｈａｖｅｂｅｅｎｏｎｅｏｆｔｈｅｍａｉｎｓｕｂｊｅｃｔｓｉｎｑｕａｎｔｕｍｏｐｔｉｃｓ．Ｕｓｕａｌｓｑｕｅｅｚｉｎｇｒｅｆｅｒｓｔｏｔｈｅｓｅｃｏｎｄｏｒｄｅｒｓｑｕｅｅｚｉｎｇ．Ｃ．Ｋ．ＨｏｎｇａｎｄＬ．Ｍａｎｄｅｌｇｅｎｅｒａｔｅｄｔｈｅｓｑｕｅｅｚｉｎｇｔｏｈｉｇｈｅ…  相似文献   

6.
1　Ｉｎｔｒｏｄｕｃｔｉｏｎ　ＴｈｅｓｐａｔｉａｌＧｒｅｅｎ’ｓｆｕｎｃｔｉｏｎｓｏｆｍｕｌｔｉ ｌａｙｅｒｅｄｍｅｄｉａａｒｅｕｓｅｆｕｌｉｎａｎａｌｙｓｉｓｏｆａｎｔｅｎｎａａｎｄｉｎｔｅｇｒａｔｅｄｃｉｒｃｕｉｔｓｔｒｕｃｔｕｒｅｓ.Ｔｈｅｙａｒｅｃｏｎｓｔｒｕｃｔｅｄｉｎｔｗｏｓｔｅｐｓ.ＴｈｅｆｉｒｓｔｉｓｔｏｄｅｒｉｖｅｔｈｅｓｐｅｃｔｒａｌＧｒｅｅｎ’ｓｆｕｎｃｔｉｏｎ .ＴｈｅｓｅｃｏｎｄｉｓｔｏｍａｋｅｉｎｖｅｒｓｅＦｏｕｒｉｅｒｔｒａｎｓｆｏｒｍｏｆｔｈｅＧｒｅｅｎ’ｓｆｕｎｃ ｔ…  相似文献   

7.
1　Ｉｎｔｒｏｄｕｃｔｉｏｎ　Ｓｑｕａｓｈｍｏｓａｉｃｖｉｒｕｓ (ＳｑＭＶ)ｉｓｏｎｅｏｆｔｈｅｍｏｓｔｉｍ ｐｏｒｔａｎｔｃｕｃｕｒｂｉｔｖｉｒｕｓｅｓ[1～ 3] ,ａｎｄｉｔｃａｕｓｅｓｇｒｅａｔｌｏｓｓｅｓｉｎｍｕｓｋｍｅｌｏｎｐｒｏｄｕｃｔｉｏｎ[4 ] .Ｏｎｅｏｆｔｈｅｍａｉｎｗａｙｓｔｏｃｏｎｔｒｏｌｐｌａｎｔｖｉｒｕｓｄｉｓｅａｓｅｓｉｓｔｈｅｉｎｄｕｃｅｍｅｎｔｏｆｒｅｓｉｓ ｔａｎｃｅｔｏｖｉｒｕｓｅｓ[5] ｂｙｓｏｍｅｂｉｏｌｏｇｉｃａｌａｎｄｎｏｎ ｂｉｏｌｏｇｉｃａｌｆａｃｔｏｒｓ[6～ 9…  相似文献   

8.
1　Ｉｎｔｒｏｄｕｃｔｉｏｎ　Ｃｏｍｐｕｔｅｒｉｎｔｅｇｒａｔｅｄｍａｎｕｆａｃｔｕｒｉｎｇ (ＣＩＭ)ａｓａｐｈｉ ｌｏｓｏｐｈｙｈａｓｒｅｃｅｉｖｅｄｗｏｒｌｄｗｉｄｅａｔｔｅｎｔｉｏｎｓｉｎｃｅｔｈｅ1980ｓａｎｄｈａｓｂｅｅｎａｐｐｌｉｅｄｔｏｄｉｒｅｃｔｅｎｔｅｒｐｒｉｓｅｓｐｒｏ ｄｕｃｔｉｏｎｓｕｃｃｅｓｓｆｕｌｌｙｉｎｍａｎｙｉｎｄｕｓｔｒｉａｌｉｚｅｄｃｏｕｎ ｔｒｉｅｓ[1] .ＴｈｅＵＳｇｏｖｅｒｎｍｅｎｔｈａｓｃｏｎｓｉｄｅｒｅｄｔｈｅｍａｎ ｕｆａｃｔｕｒｉｎｇｉｎｄｕｓｔｒｙｔｏｂ…  相似文献   

9.
1　Ｉｎｔｒｏｄｕｃｔｉｏｎ　Ｔｈｅｓｕｒｆａｃｅｔｅｘｔｕｒｅｓｔｅｅｌｓｈｅｅｔｓｈａｖｅｂｅｅｎｅｘｔｅｎｓｉｖｅｌｙｕｓｅｄｉｎａｕｔｏｍｏｂｉｌｅｉｎｄｕｓｔｒｙｆｏｒｔｈｅｉｒｇｏｏｄｆｏｒｍａｂｉｌｉｔｙａｎｄｐａｉｎｔｉｎｇｐｅｒｆｏｒｍａｎｃｅ.Ａｓｋｎｏｗｎ,ｔｈｅｒｅｅｘｉｓｔｅｓｆｒｉｃｔｉｏｎｂｅｔｗｅｅｎｔｈｅｓｈｅｅｔａｎｄｍｏｄｅｌｄｕｒｉｎｇｓｔａｍｐｉｎｇ.Ｗｈｅｎｔｈｅｓｈｅｅｔｉｓｄｅｆｏｒｍｅｄｉｎｔｏａｗｏｒｋｐｉｅｃｅ,ｔｈｅｐｒｏｃｅｓｓｏｆｓｈｅｅｔ…  相似文献   

10.
１　Ｉｎｔｒｏｄｕｃｔｉｏｎ　Ｔｈｅｓｍａｌｌｓｉｚｅ（ｄｉａｍｅｔｅｒ＜１００ｎｍ）ｏｆｕｌｔｒａｆｉｎｅｐａｒｔｉｃｌｅｓｅｎｄｏｗｓｔｈｅｍｗｉｔｈｕｎｕｓｕａｌｓｔｒｕｃｔｕｒｅ,ｅｌｅｃｔｒｏｎｉｃ,ｏｐｔｉｃａｌ,ｍａｇｎｅｔｉｃａｎｄｃｈｅｍｉｃａｌｐｒｏｐｅｒｔｉｅｓ,ｌｅａｄｉｎｇｔｏｍａｎｙｉｍｐｏｒｔａｎｔａｐｐｌｉｃａｔｉｏｎｓｓｕｃｈａｓｃａｔａｌｙｓｔｓ,ｅｌｅｃｔｒｏｏｐｔｉｃａｌｄｅｖｉｃｅｓａｎｄｆｉｎｅｃｅｒａｍｉｃｓ［１］．Ａｓｏｎｅｏｆｓｐｅｃｉａｌｆ…  相似文献   

11.
With InCl3·4H2O being used as raw materials, the precursor of nano-sized In2O3 powder was prepared by hydrolysis, peptization and gelation of InCl3·4H2O. After calcination, nano-sized In2O3 powder was obtained. The powder was characterized by thermo-gravimetric and differential thermal analysis (TG-DTA), X-ray diffractometry (XRD) and transmission electron microscopy (TEM), respectively. Calculation revealed that the mean crystalline size increased with increasing the calcination temperature, but crystal lattice distortion rate decreased with the increasing in the average crystalline size. This indicated that the smaller the particle size, the bigger the crystal lattice distortion, the worse the crystal growing. The activation energies for growth of nano-sized In2O3 were calculated to be 4.75 kJ·mol−1 at the calcination temperature up to 500°C; and 66.40 kJ·mol−1 at the calcination temperature over 600°C. TEM photos revealed that the addition of the chemical additive (OP-10) greatly influenced the morphology and size of In2O3 particles.  相似文献   

12.
Up-conversion processes for the blue, green and red emissions were found two-photon phenomenon, known as the cooperative phenomenon. This phenomenon was assisted by Nd3+ → Yb3+ → Ho3+ energy transfer. The strong green emission due to the Ho3+ : (5F4, 5S2)→ 5I8 transitions was observed in Nd3+-Ho3+ co-doped ZrF4-based fluoride glasses under 800 nm excitation. As an attempt to enhance Ho3+ up-conversion luminescences in the Nd3+ – Ho3+ co-doped ZrF4-based glasses, Yb3+ ions were added to the glasses. As a result it was found that, in 800 nm excitation of 60 ZrF4. 30BaF2. (8-x)LaF3. lNdF3. xYbF3. 1HoF3 glasses (x=0 to 7), sensitized up-conversion luminescences are observed at around 490 nm (blue), 545 nm (green), and 650 nm (red), which correspond to the Ho3+ : 5F3 → 5I8, ( 5F4, 5S2)→5I8 and 5F5→ 5I8 transitions respectively. The intensities of the green and red emissions in a 3 mol % YbF3-containing glass were about 50 times stronger than those glasses without YbF3. This is based on sensitization due to Yb3+ ions. In particular, the green emission was extremely strong and the Nd3+-Yb3+-Ho3+ co-doped ZrF4-based glasses have a high possibility of realizing a green up-conversion laser glass. In this paper the up-conversion mechanism in the glasses is discussed in detail.  相似文献   

13.
以木屑为原料,高温热解制备生物炭。以聚乙烯醇为粘结剂,采用混合法将生物炭与果胶复合,并负载磁性,经烘干定型制备果胶包覆的磁性生物炭材料（果胶@生物炭-Fe3O4）。采用扫描电镜（SEM）、X射线衍射（XRD）及N2吸附-脱附（BET）等方法对果胶@生物炭-Fe3O4进行表征,结合吸附实验分析其对Cu2+的吸附特性。结果表明,当生物炭、果胶、Fe3O4质量比为5：1：1,溶液pH值为6,吸附24 h,果胶@生物炭-Fe3O4对Cu2+吸附效果最好;二级动力学方程能较好地描述果胶@生物炭-Fe3O4对Cu2+的吸附过程,Freundlich模型能较好地拟合其吸附行为;SEM结果显示该材料具有不规则的孔隙结构;XRD分析显示纳米Fe3O4是其主要的晶体结构;BET测得其比表面积为25.654 m2·g-1,平均孔径为20.18 nm。  相似文献   

14.
1IntroductionThe synthesis and characterization of nano-struc-tured materials are the subject of intense current re-search.Hyperfineγ-Fe2O3particle with good perfor-mance,such as magnetism,catalysis,gas-sensitivityand so on,are widely applied in various fields[1].It ishighly significant to research and develop the methodsfor synthesis of nanometerγ-Fe2O3.With the development of nano-science and nano-technology,the methods for preparation ofγ-Fe2O3have been greatly progressed,for example,…  相似文献   

15.
Cucumber and rice plants with varying ammonium (NH4 +) sensitivities were used to examine the effects of different nitrogen (N) sources on gas exchange, chlorophyll (Chl) fluorescence quenching, and photosynthetic electron allocation. Compared to nitrate (NO3 −)-grown plants, cucumber plants grown under NH4 +-nutrition showed decreased plant growth, net photosynthetic rate, stomatal conductance, intercellular carbon dioxide (CO2) level, transpiration rate, maximum photochemical efficiency of photosystem II, and O2-independent alternative electron flux, and increased O2-dependent alternative electron flux. However, the N source had little effect on gas exchange, Chl a fluorescence parameters, and photosynthetic electron allocation in rice plants, except that NH4 +-grown plants had a higher O2-independent alternative electron flux than NO3 −-grown plants. NO3 − reduction activity was rarely detected in leaves of NH4 +-grown cucumber plants, but was high in NH4 +-grown rice plants. These results demonstrate that significant amounts of photosynthetic electron transport were coupled to NO3 − assimilation, an effect more significant in NO3 −-grown plants than in NH4 +-grown plants. Meanwhile, NH4 +-tolerant plants exhibited a higher demand for the reduced form of nicotinamide adenine dinucleotide phosphate (NADPH) for NO3 − reduction, regardless of the N form supplied, while NH4 +-sensitive plants had a high water-water cycle activity when NH4 + was supplied as the sole N source.  相似文献   

16.
Chemically processed Nb-doped SrTiO3 films and properties   总被引：1，自引：0，他引：1  
Homogeneous, crack-free SrNbxTi1−x O3 thin films on (110) silicon substrates were successfully fabricated by sol-gel processing. The optimum route and conditions were systematically investigated. Sr(OAc)2 glacial acctic acid solution, after being refluxed and reacted with tartrate, formed Sr(OAc)2(C4H6O6)2; Ti(OBu)4 formed Ti(OAc)4−x (AcAc)x after having the ligand partially exchanged with AcAc, while Nb(OC2H5)5 formed (OAc)2Nb(AcAc) (C4H6O6) by exchanging of ligand in glacial acetic acid with (CH3CO)2O. All the metal species after undergoing partial hydrolysis and polymerization with hydroxyl or oxygen, formed SrNbxTi1−x O13 cluster sol. Methyl cellulose (MCL) caused SrNbxTi1−x O3 sol to have polymeric structure and easily form films. SrNbxTi1−x O3 films with perovskite were subsequently formed after being annealed at 650∼750 °C for 60 min in 25% N2+75% H2 (volume ratio) atmosphere. Resistivity of the SrNb0.1Ti0.9O3 films at room temperature was 64 μω·cm, a particular T 2 temperature dependence of the resistivity, from 25 K up to room temperature, was observed. Project (No. 2002CB613305) supported by the National Basic Research Program (973) of China  相似文献   

17.
Amorphous InGaZnO (a-IGZO) films were deposited on the corning eagle XG (EXG) glass substrates using magnetron sputtering method. The structure, surface morphology, electrical and optical properties of these films were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), semiconductor parameter analyzer and spectrophotometry, respectively. The influence of oxygen flow on the electrical properties of IGZO thin films was studied, showing that increasing oxygen flow changes the resistivity with six orders of magnitude. The contact resistance of ITO/IGZO is 7.35×10−2 Ω·cm2, which suggests that a good ohmic contact exists between In2O3: Sn (ITO) and IGZO film.  相似文献   

18.
In this article, we illustrated the preparation method of γ-Al2O3 ultrafine particles. The particle size and morphology were decided by a transmission electron microscopy (TEM) and crystal patterns were determined by an X-ray diffractometer (XRD). γ-Al2O3 ultrafine particles have ultra characters in physics and chemistry, and the hydrogen peroxide biosensors based on it display not only fast response and high sensitivity, but also good stability.  相似文献   

19.
Acoustic wave propagation in piezoelectric crystals of classes?43m and 23 is studied. The crystals Tl3VS4 and Tl3TaSe4 (43m) of the Chalcogenide family and the crystal Bi12TiO20 (23) possess strong piezoelectric effect. Because the surface Bleustein-Gulyaev waves cannot exist in piezoelectric cubic crystals, it was concluded that new solutions for shear-horizontal surface acoustic waves (SH-SAWs) are found in the monocrystals using different electrical boundary conditions such as electri- cally “short” and “open” free-surfaces for the unique [101] direction of wave propagation. For the crystal Tl3TaSe4 with coefficient of electromechanical coupling (CEMC) Ke2=e2/(C×g)～1/3, the phase velocity Vph for the new SH-SAWs can be calculated with the following formula: Vph=(Va Vt)/2, where Vt is the speed of bulk SH-wave, Vt=Vt4(1 Ke2)1/2, Va=aKVt4, aK=2[Ke(1 Ke2)1/2-Ke2]1/2, and Vt4=(C44/ρ)1/2. It was found that the CEMC K2 evaluation for Tl3TaSe4 gave the value of K2=2(Vf–Vm)/Vf～0.047 (～4.7%), where Vf～848 m/s and Vm~828 m/s are the new-SAW velocities for the free and metallized surfaces, respectively. This high value of K2(Tl3TaSe4) is significantly greater than K2(Tl3VS4)～3% and about five times that of K2(Bi12TiO20).  相似文献   

20.
A series of Lil-xNaxV3O8 materials was prepared by solution reaction followed by calcination method and their electrochemical performances in 2 M LieSOa-water-ethanol solution as negative electrodes for aqueous electrolyte lithium ion battery were studied and compared each other. X-ray diffraction analysis revealed that partially substituting sodium for lithium in LiV3Os could increase the interlayer distances of （100） plane. Cyclic voltammetric experiments have demonstrated that the Li^＋ insertion and extraction kinetics of Li0.7Na0.3V3O8 is superior to that of LiV3O8. Charge/discharge results showed that the discharge specific capacity of Li0.7Na0.3V3O8 electrode is higher than that of LiV3O8 electrode.  相似文献   

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