编码曝光相机系统设计

在研究编码曝光理论基础上,设计了应用型嵌入式编码曝光相机系统。在采集运动目标图像时,按照预设的编码时序控制曝光快门,得到了光生电荷多次叠加一次转移的图像。该图像为具有编码曝光信息的运动模糊图像,有更多的图像细节信息。编码曝光图像信号经过AD转换后将数据暂存在数据存储器,再经核心器件解码模块输出复原图像。实验结果证明,编码曝光相机能有效解决线性运动模糊问题。在相同测试条件下,利用无参考图像评价指标测试,编码曝光条件下复原图像质量的指标平均值均比一般单次曝光条件下复原图像质量提高了近2倍。     

Study on formation of gels formed by polymer and zirconium acetate

The gel system used in the preparation of dispersed particle gel for water shutoff treatments, which is composed of polyacrylamides and zirconium acetate, was investigated. The gelation process, the effects of various parameters on the gelation properties, the thermal stability, and the microstructure were addressed. The cross-linking reaction process is divided into three successive steps: induction, rapid cross-linking, and stabilization. High polymer and crosslinker concentrations reduce gelation time and increase gel strength. In addition, adding salts to the brine or increasing the temperature also decrease gelation time and increase gel strength. The optimum pH for the gel system is 7.49. In field applications, this gel system is recommended to be used within 130 °C using differential scanning calorimetry. The gel formed in a three-dimensional network structure was confirmed through environmental scanning electron microscopy.     

Construction of Supramolecular Self‐Assembled Microfibers with Fluorescent Properties through a Modified Ionic Self‐Assembly (ISA) Strategy

Highly ordered supramolecular microfibers were constructed through a simple ionic self‐assembly strategy from complexes of the N‐tetradecyl‐N‐methylpyrrolidinium bromide (C₁₄MPB) surface‐active ionic liquid and the small methyl orange (MO) dye molecule, with the aid of patent blue VF sodium salt. By using scanning electron microscopy and polarized optical microscopy, the width of these self‐assembled microfibers is observed to be about 1 to 5 μm and their length is from tens of micrometers to almost a millimeter. The ¹H NMR spectra of the microfibers indicates that the supramolecular complexes are composed of C₁₄MPB and MO in equal molar ratio. The electrostatic, hydrophobic, and π–π stacking interactions are regarded as the main driving forces for the formation of microfibers. Furthermore, through characterization by using confocal fluorescence microscopy, the microfibers were observed to show strong fluorescent properties and may find potential applications in many fields.     

最小二乘法在聚合物有效物含量评价方法研究中的应用

为了彻底排除各种无机盐杂质的影响,真实地评价聚合物产品的有效成分含量,研究了醇酸共洗法测试钻井液用聚合物类降滤失剂有效物的可行性。该方法不但可有效地去除样品中的残留碱、水溶性无机盐类,同时还可以有效地去除样品中的酸溶性无机盐(如碳酸盐等)。在进行实验数据处理时,考虑标准碳酸钙的加入量与样品有效物含量测试结果间有较明显的线性关系,运用最小二乘法及加标回测外推法等统计学工具,最大限度地降低了测试结果的不确定度,提高了方法的准确度与可靠性,形成了较完善的钻井液用聚合物类降滤失剂产品有效物含量的评价方法。目前该方法已成功地应用于Q/SHCG 35-201《2钻井液用合成聚合物降滤失剂技术要求》等多个石化行业一级企业技术标准。     

Tunable continuous-wave laser at quasi-three-level with a disordered Nd:LGS crystal

A diode-pumped tunable CW Nd(3+):LGS laser at quasi-three-level has been demonstrated. The output power up to 403 mW at the central wavelength of 904 nm was obtained, corresponding to a slope efficiency of 29.7%. Taking advantage of the broad emission spectrum of the disordered crystal Nd:LGS, we tuned the laser wavelength within the spectral range of 899.8 to 906.6 nm with an etalon inserted into the V-type cavity. To the best of our knowledge, it is the first time to obtain a tunable laser based on the (4)F(3/2)-(4)I(9/2) transition of Nd(3+)-doped crystals.     

Preparation of the novel fluorine-18-labeled VIP analog for PET imaging studies using two different synthesis methods

Vasoactive intestinal peptide (VIP) receptors are expressed on various tumor cells in much higher density than somatostatin receptors, which provides the basis for radiolabeling VIP as tumor diagnostic agent. However, fast proteolytic degradation of VIP in vivo limits its clinical application. With the aim to develop and evaluate new ligands for depicting the VIP receptors with positron emission tomography (PET), the structure modified [R^8,15,21, L¹⁷]-VIP analog was radiolabeled with ¹⁸F using two different methods. With the first method, N-4-[¹⁸F]fluorobenzoyl-[R^8,15,21, L¹⁷]-VIP ([¹⁸F]FB-[R^8,15,21, L¹⁷]-VIP 7) was produced in a decay-corrected radiochemical yield (RCY) of 33.6 ± 3%, a specific radioactivity of 255 GBq/μmol (n = 5) within 100 min in four steps. Similarly, N-4-[¹⁸F](fluoromethyl)-benzoyl-[R^8,15,21, L¹⁷]-VIP ([¹⁸F]FMB-[R^8,15,21, L¹⁷]-VIP 8) was synthesized in a RCY of 34.85 ± 5%, a specific radioactivity of 180 GBq/μmol (n = 5) within 60 min in only one step. The two products 7 and 8 were both shown good stability in HSA. Moreover, the low bone uptakes of 7 and 8 in vivo of mice showed good defluorination stability.     

A Layered P2‐ and O3‐Type Composite as a High‐Energy Cathode for Rechargeable Sodium‐Ion Batteries

A layered composite with P2 and O3 integration is proposed toward a sodium‐ion battery with high energy density and long cycle life. The integration of P2 and O3 structures in this layered oxide is clearly characterized by XRD refinement, SAED and HAADF and ABF‐STEM at atomic resolution. The biphase synergy in this layered P2+O3 composite is well established during the electrochemical reaction. This layered composite can deliver a high reversible capacity with the largest energy density of 640 mAh g^?1, and it also presents good capacity retention over 150 times of sodium extraction and insertion.     

高载量、高活性Ni/Al2O3催化剂的制备及其芳环加氢催化反应

使用共沉淀法制备了担载量很高的Ni/Al2O3催化剂,通过正丁醇干燥处理,提高了催化剂的表面积和担载镍的分散度.实验发现,镍的担载量和干燥过程刘催化剂的表面积、孔结构及金属镍的还原度和分散度影响很大.经过正丁醇处理的80%Ni/Al2O3-B催化剂具有较高的表面积,而担载镍的还原度和分散度也显著提高,使得催化剂具有很高...     

Continuous-time random walk models of DNA electrophoresis in a post array: part II. Mobility and sources of band broadening

Using the two-state, continuous-time random walk model, we develop expressions for the mobility and the plate height during DNA electrophoresis in an ordered post array that delineate the contributions due to (i) the random distance between collisions and (ii) the random duration of a collision. These contributions are expressed in terms of the means and variances of the underlying stochastic processes, which we evaluate from a large ensemble of Brownian dynamics simulations performed using different electric fields and molecular weights in a hexagonal array of 1 μm posts with a 3 μm center-to-center distance. If we fix the molecular weight, we find that the collision frequency governs the mobility. On the contrary, the average collision duration is the most important factor for predicting the mobility as a function of DNA size at constant Péclet number. The plate height is reasonably well described by a single post rope-over-pulley model, provided that the extension of the molecule is small. Our results only account for dispersion inside the post array and thus represent a theoretical lower bound on the plate height in an actual device.