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1.
An improved glucose-chelator-albumin bioconjugate (GluCAB) derivative, GluCAB-2Mal, has been synthesized and studied for in vivo 64Cu-PET/CT imaging in breast cancer mice models together with its first-generation analogue GluCAB-1Mal. The radioligand works on the principle of tumor targeting through the enhanced permeability and retention (EPR) effect with a supportive role played by glucose metabolism. [64Cu]Cu-GluCAB-2Mal (99 % RCP) exhibited high serum stability with immediate binding to serum proteins. In vivo experiments for comparison between tumor targeting of [64Cu]Cu-GluCAB-2Mal and previous-generation [64Cu]Cu-GluCAB-1Mal encompassed microPET/CT imaging and biodistribution analysis in an allograft E0771 breast cancer mouse model. Tumor uptake of [64Cu]Cu-GluCAB-2Mal was clearly evident with twice as much accumulation as compared to its predecessor and a tumor/muscle ratio of up to 5 after 24 h. Further comparison indicated a decrease in liver accumulation for [64Cu]Cu-Glu-CAB-2Mal.  相似文献   
2.
The heterogeneous catalysis of transesterification of gmelina seed oil to biodiesel is evaluated. The oil was extracted from the seeds with n‐hexane by solvent extraction and characterized to determine its physiochemical properties. Response surface methodology was applied to optimize the effect of process variables on the biodiesel yield. The base‐activated clay catalyst performed as montmorillonite clay with the characteristic property of a Brønsted acid. It has an improved surface area after activation that enhanced its catalytic activity on transesterification reaction. Under optimal conditions, the biodiesel yield was 70.1 %, thus demonstrating that the model predicted well the biodiesel production.  相似文献   
3.
The aim of this paper is to investigate the long and short-run relationship between spot and futures prices of the energy, precious metals, and base metals markets. We analyze daily data from January 1985 to February 2019. The empirical findings based on the cointegration test, which follows a nonlinear process, suggest that the spot prices of energy and metals assets have long-run relationships with their futures prices. Nonparametric Granger causality test results also indicate bi-directional causality among futures and spot prices. These findings indicate that the energy and metals markets are informationally efficient in the sense of Fama (1970).  相似文献   
4.
选择了几份典型的外墙外保温系统标准,通过对这几份标准中胶粘剂和抹面胶浆的成型和检测方法的比较,分析了现有检测技术的优劣,并结合工作实践提出了建议。  相似文献   
5.
The effects of Sr2+ substitution for Ba2+ on microwave dielectric properties and crystal structure of Ba3-xSrx(VO4)2 (0 ≤ x ≤ 3, BSVO) solid solution were investigated. Such Sr2+ substitution contributes to significant reduction in sintering temperature from 1400 °C to 1150 °C. Both permittivity (r) and quality factor (Q × f) values decreased with increasing x value, which was determined to be related with the descending values of average polarizability and packing fraction, whereas the increase in τf value was explained by the decreased average VO bond length, A-site bond valence. BSVO ceramics possessed encouraging dielectric performances with r = 12.2–15.6 ± 0.1, Q × f = 44,340 - 62,000 ± 800 GHz, and τf = 24.5–64.5 ± 0.2 ppm/°C. Low-temperature sintering was manipulated by adding B2O3 as sintering additive for the representative Sr3V2O8 (SVO) ceramic and only 1 wt.% B2O3 addition successfully contributed to a 21.7% decrease in sintering temperature to 900 °C, showing good chemical compatibility with silver electrodes, which render BSVO series and SVO ceramics potential candidates in multilayer electronic devices fabrication.  相似文献   
6.
The study evaluates use of Kollidon VA®64 and a combination of Kollidon VA®64 with Kollidon VA®64 Fine as excipient in direct compression process of tablets. The combination of the two grades of material is evaluated for capping, lamination and excessive friability. Inter particulate void space is higher for such excipient due to the hollow structure of the Kollidon VA®64 particles. During tablet compression air remains trapped in the blend exhibiting poor compression with compromised physical properties of the tablets. Composition of Kollidon VA®64 and Kollidon VA®64 Fine is evaluated by design of experiment (DoE). A scanning electron microscopy (SEM) of two grades of Kollidon VA®64 exhibits morphological differences between coarse and fine grade. The tablet compression process is evaluated with a mix consisting of entirely Kollidon VA®64 and two mixes containing Kollidon VA®64 and Kollidon VA®64 Fine in ratio of 77:23 and 65:35. A statistical modeling on the results from the DoE trials resulted in the optimum composition for direct tablet compression as combination of Kollidon VA®64 and Kollidon VA®64 Fine in ratio of 77:23. This combination compressed with the predicted parameters based on the statistical modeling and applying main compression force between 5 and 15?kN, pre-compression force between 2 and 3?kN, feeder speed fixed at 25?rpm and compression range of 45–49?rpm produced tablets with hardness ranging between 19 and 21?kp, with no friability, capping, or lamination issue.  相似文献   
7.
A dense heterogeneous cellular network can effectively increase the system capacity and enhance the network coverage. It is a key technology for the new generation of the mobile communication system. The dense deployment of small base stations not only improves the quality of network service, but also brings about a significant increase in network energy consumption. This paper mainly studies the energy efficiency optimization of the Macro-Femto heterogeneous cellular network. Considering the dynamic random changes of the access users in the network, the sleep process of the Femto Base Stations (FBSs) is modeled as a Semi-Markov Decision Process (SMDP) model in order to save the network energy consumption. And further, this paper gives the dynamic sleep algorithm of the FBS based on the value iteration. The simulation results show that the proposed SMDP-based adaptive sleep strategy of the FBS can effectively reduce the network energy consumption.  相似文献   
8.
通过施工实例分析,归纳施工中常遇到的地基基础问题类型及其处理方法。结合施工经验,指出地基基础工程施工中应当避免发生的各类问题。  相似文献   
9.
West 8:大众文化图景下的当代景观   总被引:2,自引:0,他引:2  
张斌 《时代建筑》2002,(6):92-99
West8通过他们的设计观念及作品表明.面对商业主义消费社会大众文化的平庸化侵蚀,当代景观的塑造需要一种乐观主义精神以及对于建筑、规划景观、工业设计等多学科领域的充分整合。  相似文献   
10.
Vegetation uptake of nitrogen and base cations may be an important source of soil acidity. In this study, the uptake rate of nitrogen and base cations was estimated for each major vegetation type in China. Although the uptake rates of most vegetation types are lower than 2.0 keq ha(-1) a(-1), great variations exist because of the significant differences in net primary productivity and elemental composition. Uptake rates decreased gradually from southeast to northwest, except for the wide-distributed agricultural areas in the east of China, where the nitrogen and base cation uptake rates are near zero. It is evident that this pattern coincides well with the distribution of the annual mean precipitation. However, the geographical distribution of the base cation uptake rate is not entirely the same as that of nitrogen, which indicates the importance of soil conditions in determining the chemical component and hence the uptake rate of different vegetation. The acidity input caused by vegetation uptake is quite high (>0.5 keq ha(-1) a(-1)), and even higher than the current acid deposition and the alkalinity produced by soil weathering in some areas, which indicates that the growth of the plants may contribute significantly to the soil acidification problem in China.  相似文献   
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