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141.
David Casanova 《Journal of computational chemistry》2013,34(9):720-730
The restricted active space configuration interaction (RASCI) formalism with the hole and particle truncation of the wavefunction, that is, RASCI(h,p), holds very nice properties such as balanced treatment of ground and low‐lying excited states, spin‐completeness, large flexibility of the wavefunction, and moderate computational cost. In this article, I present a new implementation of the RASCI(h,p) method using a general algorithm based on the integral‐driven approach. The new implementation allows to choose any electronic configuration as the single reference in combination with an excitation operator with any number of ionization, electron attachment, or spin‐flip (SF) excitations. The applicability and good performance of the new computational code is tested in the ground state calculation of water molecule with increasingly large active spaces and up to the full‐CI limit, the calculation of all‐trans linear polyenes with variable number of SF excitations, and the low‐lying states of fluorine molecule with a double‐ionization potential operator. © 2012 Wiley Periodicals, Inc. 相似文献
142.
Dr. Toby Passioura Prof. Dr. Hiroaki Suga 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(21):6530-6536
Noncanonical peptides occur frequently in Nature, and often display high bioactivity. However, the lack of tractable systems for the synthesis of diverse libraries of such peptides has thus far hampered their development as drugs. Genetic reprogramming techniques, in which noncanonical amino acids may be incorporated into peptides, have largely removed this limitation. This Concept article outlines the development of these techniques with an emphasis on drug discovery. 相似文献
143.
ESD control programs that are based on the standards IEC61340-5-1 and ANSI/ESD S20.20 are targeted to provide safer handling of electronic parts now susceptible to damage by electrostatic discharge. However, ESD failures have occurred in EPA even when all standard control methods are met. To further improve EPAs, ESD control programs should be updated to cover all known common discharge scenarios, and multiple parallel ESD source parameters should be used to assess the level of ESD risks. In addition, a reliable ESD risk assessment should be based on discharge source circuit analysis and product sensitivity tests using the real discharge waveforms found in EPA. 相似文献
144.
In light of the generator polynomials of constacyclic codes over finite chain rings, the depth spectrum of constacyclic codes can be determined if (n,p)=1. 相似文献
145.
A q‐ary code of length n, size M, and minimum distance d is called an code. An code with is said to be maximum distance separable (MDS). Here one‐error‐correcting () MDS codes are classified for small alphabets. In particular, it is shown that there are unique (5, 53, 3)5 and (5, 73, 3)7 codes and equivalence classes of (5, 83, 3)8 codes. The codes are equivalent to certain pairs of mutually orthogonal Latin cubes of order q, called Graeco‐Latin cubes. 相似文献
146.
147.
Nanxi Wang Dr. Yue Li Dr. Wei Niu Dr. Ming Sun Dr. Ronald Cerny Prof. Qingsheng Li Prof. Jiantao Guo 《Angewandte Chemie (International ed. in English)》2014,53(19):4867-4871
A safe and effective vaccine against human immunodeficiency virus type 1 (HIV‐1) is urgently needed to combat the worldwide AIDS pandemic, but still remains elusive. The fact that uncontrolled replication of an attenuated vaccine can lead to regaining of its virulence creates safety concerns precluding many vaccines from clinical application. We introduce a novel approach to control HIV‐1 replication, which entails the manipulation of essential HIV‐1 protein biosynthesis through unnatural amino acid (UAA*)‐mediated suppression of genome‐encoded blank codon. We successfully demonstrate that HIV‐1 replication can be precisely turned on and off in vitro. 相似文献
148.
Jeffery M. Tharp Omer Ad Kazuaki Amikura Fred R. Ward Emma M. Garcia Jamie H. D. Cate Alanna Schepartz Dieter Sll 《Angewandte Chemie (International ed. in English)》2020,59(8):3122-3126
By transplanting identity elements into E. coli tRNAfMet, we have engineered an orthogonal initiator tRNA (itRNATy2) that is a substrate for Methanocaldococcus jannaschii TyrRS. We demonstrate that itRNATy2 can initiate translation in vivo with aromatic non‐canonical amino acids (ncAAs) bearing diverse sidechains. Although the initial system suffered from low yields, deleting redundant copies of tRNAfMet from the genome afforded an E. coli strain in which the efficiency of non‐canonical initiation equals elongation. With this improved system we produced a protein containing two distinct ncAAs at the first and second positions, an initial step towards producing completely unnatural polypeptides in vivo. This work provides a valuable tool to synthetic biology and demonstrates remarkable versatility of the E. coli translational machinery for initiation with ncAAs in vivo. 相似文献
149.
国家体育场馆建设行业标准已对建筑声学指标做了明确规定,在对南京奥体中心体育馆进行声学设计时,发现现行体育馆声学标准还有值得商榷的地方,特别是对大型或特大型体育馆。结合体育馆的使用功能、建筑结构,分析了体育馆声学设计的特点、目的、方法。指出:体育馆声学设计的概念应该是建筑声学和扩声系统设计的统一体;体育馆不存在传统最佳混响时间的概念,体育馆“最佳混响”就是混响时间和扩声系统结合达到的最佳清晰度概念;现行体育馆建筑声学标准中混响时间可以放宽,其意义在于扩声系统和声学装修的优化结合,从而节约国家相关建设投资。 相似文献
150.