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21.
适用于ICF靶夹持的多用微夹持器   总被引:1,自引:0,他引:1       下载免费PDF全文
针对惯性约束聚变靶零件的特点和靶装配应用环境,研制了一种多用微夹持器。该微夹持器以压电陶瓷驱动柔性钳体,集成张合量和夹持力控制功能,可更换各种形状夹口和调整夹口初始开口距离,以适应多种靶零件的夹持。利用有限元分析方法对钳体柔性机构进行了优化设计。通过检测钳体张合时不同部位柔性铰链的应变量,实现了张合量和夹持力的独立控制,并对张合量和夹持力进行了精确标定。实验结果表明:微夹持器张合量达到1 320 m,其控制分辨力为5 m;夹持力为365.0 mN,其控制分辨力1.3 mN。  相似文献   
22.
Multiple-scattering effects of atmosphere aerosols are of interest for remote sensing, free-space communications, and atmosphere detection. In the present work, the multiple-scattering effects of atmosphere aerosols on light-transmission measurements are, for the first time, investigated through numerical simulations based on the Monte Carlo method. For different extinction coefficients of the atmosphere, the multiple-scattering effects are discussed with respect to the aerosol asymmetry factor and the intended optical system parameters such as the baseline length, the area of the photoelectronic detector, and the field of view. As the simulation results, the total photon energies of scattering of each order are demonstrated. It is shown that the multiple-scattering effects are influenced by all the mentioned factors, as expected. Our work is useful for improving the optical systems based on the light-transmission measurements that are widely employed in weather observation and aerosol characterizations.  相似文献   
23.
大孔阳离子交换树脂对井冈霉素的吸附研究   总被引:4,自引:0,他引:4  
比较了5种大孔树脂与常用的001×4凝胶树脂对井冈霉素的静态和动态吸附的性能实验,并选择了其中几种有代表性的树脂,研究其对井冈霉素的吸附特性及其机理.采用正交试验筛选出具有较大吸附量的大孔强酸性阳离子树脂HD-8,并对其工艺条件进行了优化,其较优吸附能力为15.34mg/ml树脂h;同时考察了HD-8树脂的解吸行为,发现用1mol/L的氨水:80%乙醇=1:1洗脱率为98.8%,洗脱效果明显.  相似文献   
24.
计算机制全息图探究及实现   总被引:1,自引:0,他引:1  
介绍了计算机制全息图的原理,并对立体物体波场信息进行记录和立体像的复现进行了实验研究.实验结果表明:用合成全息图的方法可以实现立体成像,并利用液晶光阀系统代替干板可以简化照相制版操作.  相似文献   
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26.
MXenes are a new family of 2 D transition metal carbides and nitrides, which have attracted enormous attention in electrochemical energy storage, sensing technology, and catalysis owing to their good conductivity, high specific surface area, and excellent electrochemical properties. In this work, a series of Co3O4-doped 3 D MXene/RGO hybrid porous aerogels is designed and prepared through a facile in situ reduction and thermal annealing process, in which the reduced graphene oxide (RGO) conductive network can electrically link the separated Co3O4-MXene composite nanosheets, leading to enhanced electronic conductivity. It is found that upon using the Co3O4-MXene/RGO hybrid porous aerogel prepared with a mass ratio of Co3O4-MXene/RGO of 3:1 (CMR31) as an electrode for a supercapacitor, a superior specific capacitance of 345 F g−1 at the current density of 1 A g−1 is achieved, which is significantly higher than those of Ti3C2Tx MXene, RGO, and MXene/RGO electrodes. In addition, a high capacitance retention (85 % of the initial capacitance after 10 000 cycles at a high current density of 3 A g−1) and a low internal resistance Rs (0.44 Ω) can be achieved. An all-solid-state asymmetric supercapacitor (ASC) device is assembled using CMR31, and it has the ability to light up a blue LED indicator for 5 min if four ASCs are connected in series. Therefore, these novel Co3O4-MXene/RGO hybrid porous aerogels have potential practical applications in high-energy storage devices.  相似文献   
27.
From diagnosis of life‐threatening diseases to detection of biological agents in warfare or terrorist attacks, biosensors are becoming a critical part of modern life. Many recent biosensors have incorporated carbon nanotubes as sensing elements, while a growing body of work has begun to do the same with the emergent nanomaterial graphene, which is effectively an unrolled nanotube. With this widespread use of carbon nanomaterials in biosensors, it is timely to assess how this trend is contributing to the science and applications of biosensors. This Review explores these issues by presenting the latest advances in electrochemical, electrical, and optical biosensors that use carbon nanotubes and graphene, and critically compares the performance of the two carbon allotropes in this application. Ultimately, carbon nanomaterials, although still to meet key challenges in fabrication and handling, have a bright future as biosensors.  相似文献   
28.
对用单能中子源作活化截面测量时低能中子干扰的影响作了分析研究,并从测量的两种常用中子源T(d,n)4He和D(d,n)3He的中子源能谱中验证了这种定性分析.最后给出了两个比较典型的反应58Ni(n,P)58Co和64Zn(,P)64Cu反应的截面测量结果.  相似文献   
29.
Graphene–polymer composites of positive‐charged poly(dimethyl aminoethyl acrylate), negative‐charged poly(acrylic acid), and neutral polystyrene were prepared by “graft from” methodology using reversible addition fragmentation chain transfer (RAFT) polymerization via a pyrene functional RAFT agent (PFRA) modified graphene precursor. Fluorescence spectroscopy and attenuated total reflection infrared (ATR‐IR) evidenced that the PFRA was attached on the graphene basal planes by π–π stacking interactions, which is strong enough to anti‐dissociation in the polymerization mixture up to 80°C. Atomic force microscopy (AFM) revealed that the thickness of a graphene–polymer sheet was about 4.0 nm. Graphene composites of different polymers with the same polymerization degree exhibited similar conductivity; however, when the polymer chain was designed as random copolymer the conductivity was significantly decreased. It was also observed that the longer the grafted polymer chains the lower the conductivity. ATRIR spectroscopy and thermogravimetric analysis were also performed to characterize the as‐prepared composites. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   
30.
The outstanding electrocatalytic activity of ruthenium (Ru) phosphides toward the hydrogen evolution reaction (HER) has received wide attention. However, the effect of the Ru phosphide phase on the HER performance remains unclear. Herein, a two-step method was developed to synthesize nanoparticles of three types of Ru phosphides, namely, Ru2P, RuP, and RuP2, with similar morphology, dimensions, loading density, and electrochemical surface area on graphene nanosheets by simply controlling the dosage of phytic acid as P source. Electrochemical tests revealed that Ru2P/graphene shows the highest intrinsic HER activity, followed by RuP/graphene and RuP2/graphene. Ru2P/graphene affords a current density of 10 mA cm−2 at an overpotential of 18 mV in acid media. Theoretical calculations further showed that P-deficient Ru2P has a lower free energy of hydrogen adsorption on the surface than other two, P-rich Ru phosphides (RuP, RuP2), which confirms the excellent intrinsic HER activity of Ru2P and is consistent with experiment results. The work reveals for the first time a clear trend of HER activity among three Ru phosphide phases.  相似文献   
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