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排序方式: 共有315条查询结果,搜索用时 78 毫秒
1.
Jiwon Lee Bryan S. Der Christos S. Karamitros Wenzong Li Nicholas M. Marshall Oana I. Lungu Aleksandr E. Miklos Jianqing Xu Tae Hyun Kang Chang-Han Lee Bing Tan Randall A. Hughes Sang Taek Jung Gregory C. Ippolito Jeffrey J. Gray Yan Zhang Brian Kuhlman George Georgiou Andrew D. Ellington 《American Institute of Chemical Engineers》2020,66(3):e16864
We used the molecular modeling program Rosetta to identify clusters of amino acid substitutions in antibody fragments (scFvs and scAbs) that improve global protein stability and resistance to thermal deactivation. Using this methodology, we increased the melting temperature (Tm) and resistance to heat treatment of an antibody fragment that binds to the Clostridium botulinum hemagglutinin protein (anti-HA33). Two designed antibody fragment variants with two amino acid replacement clusters, designed to stabilize local regions, were shown to have both higher Tm compared to the parental scFv and importantly to retain full antigen binding activity after 2 hr of incubation at 70°C. The crystal structure of one thermostabilized scFv variants was solved at 1.6 Å and shown to be in close agreement with the RosettaAntibody model prediction. 相似文献
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3.
Microwave Sol–Gel Synthesis of CaGd2(MoO4)4:Er3+/Yb3+ Phosphors and Their Upconversion Photoluminescence Properties 下载免费PDF全文
Chang Sung Lim Victor Atuchin Aleksandr Aleksandrovsky Maxim Molokeev Aleksandr Oreshonkov 《Journal of the American Ceramic Society》2015,98(10):3223-3230
CaGd2(MoO4)4:Er3+/Yb3+ phosphors with the doping concentrations of Er3+ and Yb3+ (x = Er3+ + Yb3+, Er3+ = 0.05, 0.1, 0.2, and Yb3+ = 0.2, 0.45) have been successfully synthesized by the microwave sol–gel method, and the crystal structure refinement and upconversion photoluminescence properties have been investigated. The synthesized particles, being formed after heat‐treatment at 900°C for 16 h, showed a well‐crystallized morphology. Under the excitation at 980 nm, CaGd2(MoO4)4:Er3+/Yb3+ particles exhibited strong 525 and 550‐nm emission bands in the green region and a weak 655‐nm emission band in the red region. The Raman spectrum of undoped CaGd2(MoO4)4 revealed about 15 narrow lines. The strongest band observed at 903 cm?1 was assigned to the ν1 symmetric stretching vibration of MoO4 tetrahedrons. The spectra of the samples doped with Er and Yb obtained under 514.5 nm excitation were dominated by Er3+ luminescence preventing the recording Raman spectra of these samples. Concentration quenching of the erbium luminescence at 2H11/2→4I15/2 and 4S3/2→4I15/2 transitions in the CaGd2(MoO4)4:Er3+/Yb3+ crystal structure was established to be approximately at the 10 at.% doping level. 相似文献
4.
Alexander Pyattaev Jiri Hosek Kerstin Johnsson Radko Krkos Mikhail Gerasimenko Pavel Masek Aleksandr Ometov Sergey Andreev Jakub Sedy Vit Novotny Yevgeni Koucheryavy 《ETRI Journal》2015,37(5):877-887
This paper is a first‐hand summary on our comprehensive live trial of cellular‐assisted device‐to‐device (D2D) communications currently being ratified by the standards community for next‐generation mobile broadband networks. In our test implementation, we employ a full‐featured 3GPP LTE network deployment and augment it with all necessary support to provide real‐time D2D connectivity over emerging Wi‐Fi‐Direct (WFD) technology. As a result, our LTE‐assisted WFD D2D system enjoys the required flexibility while meeting the existing standards in every feasible detail. Further, this paper provides an account on the extensive measurement campaign conducted with our implementation. The resulting real‐world measurements from this campaign quantify the numerical effects of D2D functionality on the resultant system performance. Consequently, they shed light on the general applicability of LTE‐assisted WFD solutions and associated operational ranges. 相似文献
5.
ABRAMOV Aleksandr 《石油勘探与开发》2019,(3)
改进并测试了包含30多个钻井工程参数的技术-经济模型,通过新开发的计算机程序列出平台上的井丛分组方式并计算其技术经济效益。针对含24口初始产油量不同的井的平台,研究分析了7种钻井方案,得出了3种折现率和5种产油量递减率条件下净现值(NPV)最优的分组方式。研究表明,针对井丛井数不等的井平台,可能只需对现有设计进行轻微调整(改变几个井丛的布局)就能得到最大净现值;相对净现值增幅与净现值的绝对值成反比;相比常规项目中具有相等井数的井丛,采用井丛井数不等的分组方式可以使NPV增幅达到1%,页岩地层开发项目NPV增幅可达2%或更多,边际油田项目增幅高达45%。图9表4参18 相似文献
6.
Sergey G. Kopysov Aleksandr A. Erofeev 《The International journal of environmental studies》2015,72(3):380-385
The landscape conditions for forming the water balance and runoff from catchment areas can change considerably under the pressure of natural and anthropogenic factors. The role of hydromorphic transformation of landscapes is important for most of the Ob basin; it results in the paludification of the area. The specific parameter n is used in calculating water balance according to Mezentsev’s method of hydro-climatic calculations to take account of landscape conditions. We suggest determining this parameter’s value by geomorphological features of the landscapes using GIS tools. 相似文献
7.
Jacob L. Jones James M. LeBeau Jason Nikkel Adedapo A. Oni J. Houston Dycus Clayton Cozzan Fang‐Yin Lin Aleksandr Chernatynskiy Juan C. Nino Susan B. Sinnott Sungwook Mhin Geoff L. Brennecka Jon Ihlefeld 《Advanced Materials Interfaces》2015,2(10)
Understanding interfaces between dissimilar materials is crucial to the development of modern technologies, for example, semiconductor–dielectric and thermoelectric–semiconductor interfaces in emerging electronic devices. However, the structural characterization of buried interfaces is challenging because many measurement techniques are surface sensitive by design. When interested in interface evolution during synthesis, the experimental challenges multiply and often necessitate in situ techniques. For solution‐derived lead zirconate titanate (PZT) ferroelectric thin films, the evolution of buried interfaces during synthesis (including dielectric–metal and metal–metal) is thought to dramatically influence the resultant dielectric and ferroelectric properties. In the present work, multiple experimental and computational methods are combined to characterize interface evolution during synthesis of ferroelectric PZT films on platinized Si wafers—including in situ X‐ray diffraction during thermal treatment, aberration‐corrected scanning transmission electron microscopy of samples quenched from various synthesis states, and calculations using density functional theory. Substantial interactions at buried interfaces in the PZT/Pt/Ti/SiO x /Si heterostructure are observed and discussed relative to their role(s) in the synthesis process. The results prove that perovskite PZT nucleates directly from the platinum (111)‐oriented bottom electrode and reveal the roles of Pb and O diffusion and intermetallic Pt3Pb and Pt3Ti phases. 相似文献
8.
Aleksandr Krinitsyn Sergey Nikolaev Sergey Ovchinnikov 《Journal of Superconductivity and Novel Magnetism》2014,27(4):955-963
Within a new norm-conserving approach to the cluster perturbation theory (CPT) for the 2d Hubbard model we study the effect of the cluster size and shape on the electronic structure. We have compared two type of clusters, 4-cluster (2×2) and 5-cluster (cruciform of 5 atoms). With 4-cluster we can treat exactly the first and second neighbours correlations, C 1 and C 2. With 5-cluster the third neighbour correlations C 3 are also treated exactly. The band structure in the CPT with 4- and 5-clusters differs remarkably. The quasiparticle spectral weight map for 5-clusters is very similar to the Quantum Monte Carlo (QMC) and the variational CPT data. With increasing doping, small hole Fermi surface transforms into conventional Fermi-liquid type large Fermi surface through Lifshitz quantum phase transitions. 相似文献
9.
Impett Emily A.; Gordon Amie M.; Kogan Aleksandr; Oveis Christopher; Gable Shelly L.; Keltner Dacher 《Canadian Metallurgical Quarterly》2010,99(6):948
In 2 daily experience studies and a laboratory study, the authors test predictions from approach-avoidance motivational theory to understand how dating couples can maintain feelings of relationship satisfaction in their daily lives and over the course of time. Approach goals were associated with increased relationship satisfaction on a daily basis and over time, particularly when both partners were high in approach goals. Avoidance goals were associated with decreases in relationship satisfaction over time, and people were particularly dissatisfied when they were involved with a partner with high avoidance goals. People high in approach goals and their partners were rated as relatively more satisfied and responsive to a partner's needs by outside observers in the lab, whereas people with high avoidance goals and their partners were rated as less satisfied and responsive. Positive emotions mediated the link between approach goals and daily satisfaction in both studies, and responsiveness to the partner's needs was an additional behavioral mechanism in Study 2. Implications of these findings for approach-avoidance motivational theory and for the maintenance of satisfying relationships over time are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
10.