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Preliminary Studies on Base Substitutions and Repair of DNA Mismatch Damage Stimulated by Low Energy N^+ Ion Beam Implantation in Escherichia coli 被引量:4
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作者 谢传晓 郭金华 +1 位作者 程备久 余增亮 《Plasma Science and Technology》 SCIE EI CAS CSCD 2003年第1期1677-1682,共6页
Ever since the low energy N+ ion beam has been accepted that the mutation effects of ionizing radiation are attributed mainly to direct or indirect damage to DNA. Evidences based on naked DNA irradiation in support of... Ever since the low energy N+ ion beam has been accepted that the mutation effects of ionizing radiation are attributed mainly to direct or indirect damage to DNA. Evidences based on naked DNA irradiation in support of a mutation spectrum appears to be consistent, but direct proof of such results in vivo are limited. Using mutS, dam and/or dcm defective Eschericha coli imitator strains, an preliminary experimental system on induction of in vivo mutation spectra of low energy N+ ion beam has been established in this study. It was observed that the mutation rates of rifampicin resistance induced by N+ implantation were quite high, ranging from 9.2 x 10~8 to 4.9× 10~5 at the dosage of 5.2×1014 ions/cm2. Strains all had more than 90-fold higher mutation rate than its spontaneous mutation rate determined by this method. It reveals that base substitutions involve in induction of mutation of low energy nitrogen ion beam implantation. The mutation rates of mutator strains were nearly 500-fold (GM2929), 400-fold (GM5864) and 6-fold larger than that of AB1157. The GM2929 and GM5864 both lose the ability of repair DNA mismatch damage by virtue of both dam and dcm pathways defective (GM2929) or failing to assemble the repair complex (GM5864) respectively. It may explain the both strains had a similar higher mutation rate than GM124 did. It indicated that DNA cytosine methylase might play an important role in mismatch repair of DNA damage induced by N+ implantation. The further related research were also discussed. 展开更多
关键词 low energy N^+ ion beam base substitutions dam(DNA adenine methylase) dcm(DNA cytosine methylase) MUTS MMR (mismatch repair) Escherichia coli mutator strain
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Real-world efficacy of daclatasvir and asunaprevir with respect to resistance-associated substitutions 被引量:3
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作者 Hideki Fujii Atsushi Umemura +12 位作者 Taichiro Nishikawa Kanji Yamaguchi Michihisa Moriguchi Hideki Nakamura Kohichiroh Yasui Masahito Minami Saiyu Tanaka Hiroki Ishikawa Hiroyuki Kimura Shiro Takami Yasuyuki Nagao Toshihide Shima Yoshito Itoh 《World Journal of Hepatology》 CAS 2017年第25期1064-1072,共9页
AIM To investigate daclatasvir(DCV)and asunaprevir(ASV)efficacy in hepatitis C(HCV)patients,with respect to resistance-associated substitutions(RASs).METHODS A total of 392 HCV-infected patients from multiple centers ... AIM To investigate daclatasvir(DCV)and asunaprevir(ASV)efficacy in hepatitis C(HCV)patients,with respect to resistance-associated substitutions(RASs).METHODS A total of 392 HCV-infected patients from multiple centers were included in this study.We evaluated their clinical courses and sustained virologic responses(SVR)according to pretreatment factors(gender,age,history of interferon-based regimens,platelet counts,level of viremia,pretreatment NA5A:L31,and Y93 substitutions).We also analyzed the pretreatment and post-treatment major RASs of NS3:D168,NS5A:L31 and Y93 substitutions using a direct-sequencing method in 17 patients who were unable to achieve SVR at 12 wk after treatment completion(SVR12).RESULTS The overall SVR12 rate was 88.3%.Thirty-one patients discontinued treatment before 24 wk because of adverse events,23 of whom achieved SVR12.There were no significant differences in SVR12 rates with respect to gender,age,history of interferon-based regimens,and platelet counts.The SVR12 rate in patients with viral loads of≥6.0 log IU/m L was significantly lower than those with viral loads of<6.0 log IU/m L(P<0.001).The SVR12 rate in patients with Y93 substitution-positive was significantly lower than those with Y93 substitution-negative(P<0.001).The L31 substitution-positive group showed a lower SVR12 rate than the L31 substitution-negative group,but the difference was not statistically significant.Seventeen patients who did not achieve SVR12 and had available pretreatment and post-treatment sera had additional RASs in NS3:D168,NS5:L31,and Y93 substitution at treatment failure.CONCLUSION Combination of DCV and ASV is associated with a high SVR rate.Baseline RASs should be thoroughly assessed to avoid additional RASs after treatment failure. 展开更多
关键词 Hepatitis C Asunaprevir Combination therapy Resistance-associated substitutions Daclatasvir
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Physicochemical, Biochemical and Instrumental Attributes and Consumer Acceptability of Dry-Fermented Sausages Elaborated with Combined Partial Substitutions of Sodium Chloride and Pork Backfat 被引量:1
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作者 Hassan Safa Philippe Gatellier +5 位作者 Jean-Louis Berdagué Nathalie Kondjoyan Frédéric Mercier Stéphane Portanguen Raphaël Favier Pierre-Sylvain Mirade 《Food and Nutrition Sciences》 2016年第14期1297-1314,共18页
We performed 6 fabrications of dry-fermented sausages to investigate, at laboratory scale, the effects of combined partial substitutions of sodium chloride by potassium chloride and pork backfat by sunflower oil on ke... We performed 6 fabrications of dry-fermented sausages to investigate, at laboratory scale, the effects of combined partial substitutions of sodium chloride by potassium chloride and pork backfat by sunflower oil on key physical-chemical and biochemical parameters, instrumental colour and texture measurements, and the consumer acceptability of the end-products. Regarding the physical-chemical parameters, statistical analysis of results showed that final product weight loss was impacted by fat content and use of sunflower oil;final mean water activity value was only affected by salt level;and animal fat content impacted pH values, only at the end of drying. Regarding the biochemical parameters investigated, we statistically found a marked impact of partial substitution of NaCl by KCl on the proteolysis evolution, of fat level and sodium content on the end-product lipolysis, and finally, a significant effect of animal fat level and incorporation of sunflower oil on both protein and lipid oxidations. However, the new product formulations combining salt and fat substitutions lead to globally acceptable water loss and water activity values and similar rates of proteolysis, lipolysis and lipid oxidation, but less protein oxidation. From a practical point of view, the results clearly showed that sodium and animal fat contents in dryfermented sausages can be drastically reduced with no too marked adverse effect on colour, final textural properties or consumer acceptability. On the basis of these laboratory results, new healthier dry-fermented products can be manufactured by an industrial company in the near future. 展开更多
关键词 Dry-Fermented Sausage Combined Partial substitutions KCL Sunflower Oil Oxidation
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Transition Metal Substitutions Induce Ferromagnetism in Bi2Te3
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作者 鞠林 徐同帅 +3 位作者 胡丹 崔海涛 张雍家 时长民 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第2期173-178,I0001,共7页
The possibilities of magnetism induced by transition-metal atoms substitution in Bi2Te3 system are investigated by ab initio calculations. The calculated results indicate that a transition-metal atom substitution for ... The possibilities of magnetism induced by transition-metal atoms substitution in Bi2Te3 system are investigated by ab initio calculations. The calculated results indicate that a transition-metal atom substitution for a Bi atom produces magnetic moments, which are due to the spin-polarization of transition-metal 3d electrons. The values of magnetic moments are 0.92, 1.97, 2.97, 4.04, and 4.98 μB for 4% Ti-, V-, Cr-, Mn- and Fe-doped Bi2Te3 re- spectively. When substituting two transition-metal atoms, the characteristics of exchanging couple depend upon the distributions of the Bi atoms substituted. When two transition- metal atoms substituting for Bi atoms locate at the sites of Bil and Bi5, with the distance of 11.52A, the Bi1.84TM0.16Te3 system is energetically most stable and exhibits ferromagnetic coupling. 展开更多
关键词 Transition-metal atom Substitution Magnetic moment First-principles cal-culation
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Structure and Magnetic Properties of Nd-Fe-B/α-Fe Nanocomposite Magnets by Co, Nb, Dy Substitutions
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作者 Jian ZHANG Xaokai SUN +2 位作者 Wei LIU Baozhi CUI Xinguo ZHAO and Zhidong ZHANG(Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110015, China) 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1999年第3期198-202,共5页
Structure and magnetic properties of the nanocomposite magnets prepared by mechanical al loying procedure with composition 55 wt pct Nd (Fe0.92B0.08)5.5+45 wt pct α-Fe,55 wt pct Nd(Fe0.8-.Co0.12Nbx B0.08)5.5+45 wt p... Structure and magnetic properties of the nanocomposite magnets prepared by mechanical al loying procedure with composition 55 wt pct Nd (Fe0.92B0.08)5.5+45 wt pct α-Fe,55 wt pct Nd(Fe0.8-.Co0.12Nbx B0.08)5.5+45 wt pct α-Fe (x=0.00, 0.01- 0.03) and 55 wt pct (Nd0.9Dy0.1) (Fe0.77Co0.12Nb0.03B0.08)5.5+45 wt pct α-Fe were studied. It was found that substitution of Co for Fe could significantly improve the permanent magnetic properties of the nanocomposite magnets and typically, the maximum magnetic energy product was increased from 104.8 kJ/m3 (13.1 MGOe) to 141.6 kJ/m3 (17.7 MGOe). In contrast to the case of conventional nominally single-phase magnets, the addition of Nb results in promoting the growth of α-Fe grain and is thus unfavorable for the improvement of permanent magnetic properties of the nanocomposites. Although the addition of Dy can increase the coercivity of the magnets, the increase of magnetic anisotropy of hard phase leads to decrease of the critical grain size of soft phase. Additionally it causes the difficulty of preparing the nanocomposites because it is more difficult to control the grain size of soft phase to meet the requirement of appropriate exchange coupling between hard and soft grains 展开更多
关键词 Fe Nanocomposite Magnets by Co Dy substitutions NB Structure and Magnetic Properties of Nd-Fe-B Nd
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Behavior-Consistent Service Substitutions in Dynamic Environments
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作者 陈俊清 黄林鹏 于程远 《Journal of Shanghai Jiaotong university(Science)》 EI 2014年第1期17-27,共11页
In this paper, a novel approach for service substitutions based on the service type in terms of its interface type and behavior semantics is proposed. In order to analyze and verify behavior-consistent service substit... In this paper, a novel approach for service substitutions based on the service type in terms of its interface type and behavior semantics is proposed. In order to analyze and verify behavior-consistent service substitutions in dynamic environments, we first present a formal language to describe services from control-flow perspective, then introduce a type and effect system to infer conservative approximations of all possible behaviors of these services. The service behaviors are represented by concurrent behavior expressions (CBEs). Built upon the interpretation of CBEs, behavior-consistent service substitutions are defined and analyzed by subtyping technology. The correctness of the analysis approach is guaranteed by type safety theorem, which is mechanically proved in the Coq proof assistant. Finally, applications in web services show that our method is effective and feasible. 展开更多
关键词 behavior consistency concurrent regular expressions subtyping technology type and effiect systems service substitutions
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Analysis of the effect of HCV resistance-associated substitutions on the short-term efficacy of DAA after single administration in three phase Ib clinical trials
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作者 Jing Zhou Hong Zhang +3 位作者 Xiaojiao Li Xiangshi Song Mengmeng Zhang Yanhua Ding 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2021年第2期133-145,共13页
As crucial factors in hepatitis C virus(HCV)management,resistance-associated substitutions(RASs)are associated with the treatment outcome of some direct-acting antiviral(DAA)-based regimens.In this study,we mainly ana... As crucial factors in hepatitis C virus(HCV)management,resistance-associated substitutions(RASs)are associated with the treatment outcome of some direct-acting antiviral(DAA)-based regimens.In this study,we mainly analyzed the impact of baseline Y93 H or Y93 Y/H on the short-term efficacy after single administration of NS5 A inhibitors in three phaseⅠb clinical trials(yimitasvir phosphate,KW-136 and fopitasvir),and analyzed the prevalence of baseline RASs and treatment-emergent RASs.A total of 94 treatment-naive HCV genotype(GT)-1 b(n=63)and GT-2 a(n=31)Chinese patients were enrolled in three phase lb clinical trials.We investigated RASs in 77 patients with next generation or Sanger sequencing.In the 7-day trial of yimitasvir phosphate,the mean maximum HCV RNA decrease of patients with baseline Y93 H or Y93 Y/H was lower than that of patients without the mutation in the 30 mg and 200 mg cohorts(0.83 vs.2.45 log10 IU/mL and 1.92 vs.2.63 log10 IU/mL).In the3-day trial of KW-136,the mean maximum HCV RNA decrease in patients with baseline Y93 H or Y93 Y/H was lower than that of patients without the mutation in the 30,60 and 120 mg cohorts(1.58 vs.2.89 log10 IU/mL,3.16 vs.4.09 log10 IU/mL and3.00 vs.5.04 log10 IU/mL,respectively).In the 3-day trial of fopitasvir,only 30 mg group had baseline Y93 H or Y93 Y/H,and the average maximum HCV RNA decrease of patients with baseline Y93 H or Y93 Y/H was lower than that of patients without the mutation(1.45 vs.3.59 log10 IU/mL).In the three trials,baseline RASs were observed in 54 patients(70.1%;54/77).The most prevalent baseline RASs were Y93 H and Y93 Y/H(18.2%;14/77),followed by L3 IM(16.9%;13/77).The most common RASs after single administration of DAA were Y93 H and Y93 Y/H.Our data could provide reference for future clinical treatment and clinical trial. 展开更多
关键词 Direct acting antiviral agents Resistance-associated substitutions HCV sequencing Genotype 1b and 2a HCV NS5A inhibitors
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Mechanism of Na and K Substitutions in Bioapatite Within Salty Area
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作者 LI Zhen 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第S1期86-86,共1页
Introduction Na and K are two most important cations in salty water,and also are two typical ions in animals’body fluids.The mineral,bioapatite,is a form of carbonated hydroxylapatite,which makes up over 50 wt.%of bones
关键词 bone NA Mechanism of Na and K substitutions in Bioapatite Within Salty Area
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Evidence for Base Substitutions and Repair of DNA Mismatch Damage Induced by Low Energy N^+ Ion Beam Implantation in E. coli
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作者 谢传晓 Guo +6 位作者 Jinhua Yao Jianmin Wu Lijun Yu Zengliang 《High Technology Letters》 EI CAS 2003年第2期1-6,共6页
Ever since the low energy N + ion beam has been accepted, the mutations of ionizing radiation are attributable mainly to avoidance of DNA damages repair. Evidences based on in vivo proof results are limited. Using the... Ever since the low energy N + ion beam has been accepted, the mutations of ionizing radiation are attributable mainly to avoidance of DNA damages repair. Evidences based on in vivo proof results are limited. Using the E.coli wild type and mutator strains, the mutant frequencies suggest that base substitutions in rpoB gene are induced by the N + implantation. A highly conserved region is selected to get the direct evidence for base substitutions by sequence of the high fidelity PCR amplification products in mutants. Most of the mutants (90.9%, 40/44) have at least one base substitution in the amplification region. The evidences for CG to TA (55%, 22/40), AT to GC (20%, 8/40) and TA to CG (5%, 2/40) transitions are identified. The transversions are AT to TA (15%, 6/40) and GC to CG (5%, 2/40). It is suggested that DNA cytosine methylase might play an important role in mismatch repair of DNA damage induced by N + implantation by analysis of the mutant frequencies of mutator strains. 展开更多
关键词 low energy N + ion beam base substitutions mismatch repair mutator strains
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Assessment of Genetic Relationship and Application of Computational Algorithm to Assess Functionality of Non-Synonymous Substitutions in DQA2 Gene of Cattle, Sheep and Goats 被引量:1
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作者 Steven B. Ugbo Abdulmojeed Yakubu +4 位作者 Jude N. Omeje Bwaseh S. Bibinu Ibrahim S. Musa Joseph O. Egahi N. I. Dim 《Open Journal of Genetics》 2015年第4期145-158,共14页
The major histocompatibility complex (MHC) is a fundamental part of the immune system in nearly all vertebrates. DQA2 is a member of the MHC complex and an important candidate gene involved in susceptibility/resistanc... The major histocompatibility complex (MHC) is a fundamental part of the immune system in nearly all vertebrates. DQA2 is a member of the MHC complex and an important candidate gene involved in susceptibility/resistance to various diseases. Therefore, the present study aimed at investigating computationally molecular genetic variation of DQA2 gene of cattle, sheep and goats especially on its evolution and differentiation within and among species as well as the attendant effects of the polymorphism on the function of DQA2 gene. A total of thirty three DQA2 nucleotide sequences comprising cattle (10), sheep (12) and goats (11) were retrieved from the GenBank. Forty seven amino acid substitutions of the wild type alleles located in the putative peptide coding region of caprine DQA2 alleles were obtained from the alignment of deduced amino acid sequences of goats. Out of these, eleven amino acid substitutions (H14L, H14R, L34M, E35L, G56S, G56R, 161V, A62E, D69Q, T72N and T72G) were returned neutral;an indication that they did not impair protein function. The Expected Accuracy (EA) ranged from 53% - 87%. For sheep, sixteen amino acid substitutions (A11P, A11T, A11G, A11M, L14S, L14T, V27L, V27S, G35S, S46T, D55E, L57T, L57A, L57G, K65Q and V68I) appeared beneficial while the rest forty seven appeared harmful (EA ranged from 53% - 93%). Twenty four amino acid substitutions did not impair the function of protein while seventy seven substitutions appeared to have a negative effect on the function of protein of cattle (EA ranged from 53% - 94%). The phylogeny based on nucleotide and amino acid sequences of DQA2 gene revealed the close relatedness of the caprine, ovine and bovine species. The present knowledge would be relevant for performing further genotype-phenotype research as well as pharmacogenetics studies in order to show association between caprine, ovine and bovine DQA2 allelic variation and the clinical progression of infectious diseases especially in a developing country such as Nigeria. 展开更多
关键词 DQA2 Genetic Relationship AMINO Acid SUBSTITUTION PHYLOGENY RUMINANTS
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Substitutions of vertex configuration of Ammann–Beenker tiling in framework of Ammann lines
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作者 Jia-Rong Ye Wei-Shen Huang Xiu-Jun Fu 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第8期500-504,共5页
The Ammann–Beenker tiling is a typical model for two-dimensional octagonal quasicrystals. The geometric properties of local configurations are the key to understanding its formation mechanism. We study the configurat... The Ammann–Beenker tiling is a typical model for two-dimensional octagonal quasicrystals. The geometric properties of local configurations are the key to understanding its formation mechanism. We study the configuration correlations in the framework of Ammann lines, giving an in-depth inspection of this eightfold symmetric structure. When both the vertex type and the orientation are taken into account, strict confinements of neighboring vertices are found. These correlations reveal the structural properties of the quasilattice and also provide substitution rules of vertex along an Ammann line. 展开更多
关键词 QUASICRYSTALS Ammann–Beenker tiling Ammann lines substitution rules
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THE STRUCTURE OF INVERTIBLE SUBSTITUTIONS ON A THREE-LETTER ALPHABET
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作者 Tan Bo Wen Zhixiong Zhang Yiping (Wuhan University,China) 《Analysis in Theory and Applications》 2003年第4期365-382,共18页
We study the structure of invertible substitutions on three-letter alphabet. We show that there exists a finite set S of invertible substitutions such that any invertible substitution can be written as I wσ 1σ ... We study the structure of invertible substitutions on three-letter alphabet. We show that there exists a finite set S of invertible substitutions such that any invertible substitution can be written as I wσ 1σ 2…σ k,where I w is the inner automorphism associated with w, and σ j∈ S for 1≤j≤k. As a consequence,M is the matrix of an invertible substitution if and only if it is a finite product of non-negative elementary matrices. 展开更多
关键词 invertible substitution indecomposable substitution combinatorics of words
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The Majorization Order on Monomials and Termination of the Successive Difference Substitutions
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作者 Jia XU Yong YAO 《Journal of Mathematical Research with Applications》 CSCD 2015年第2期229-236,共8页
We introduce a concept for the majorization order on monomials. With the help of this order, we derive a necessary condition on the positive termination of a general successive difference substitution algorithm (KSDS... We introduce a concept for the majorization order on monomials. With the help of this order, we derive a necessary condition on the positive termination of a general successive difference substitution algorithm (KSDS) for an input form f. 展开更多
关键词 successive difference substitution algorithm majorization order on monomials TERMINATION positive semi-definite form
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Roles of metal element substitutions from the bimetallic solid state electrolytes in lithium batteries 被引量:2
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作者 Wen Yu Nanping Deng +3 位作者 Lin Tang Kewei Cheng Bowen Cheng Weimin Kang 《Particuology》 SCIE EI CAS CSCD 2022年第6期51-71,共21页
All-solid-state lithium batteries(ASSLBs),receiving extensive attentions and studies,exhibit better safety,environmental friendliness,stability,wider electrochemical stability window and higher energy density than tra... All-solid-state lithium batteries(ASSLBs),receiving extensive attentions and studies,exhibit better safety,environmental friendliness,stability,wider electrochemical stability window and higher energy density than traditionally liquid lithium batteries.In a variety of inorganic materials,with highly replaceable,the non-lithium metal elements emerge in endlessly and affect performances in diversiform ways.Due to facile preparation,convertible structures and excellent properties,the lithium-containing bimetallic granular materials are often applied as important components of electrolytes in lithium batteries.In this review,in terms of the properties of substituted elements,changing crystal structures,increasing vacancies or defects and improving the interfacial conductions,the roles of metal element substitutions of inorganic particles on the improvement of solid-state electrolytes are expounded.And the applications of substituted strategies in ASSLBs as the host of inorganic particles electrolytes and as fillers or modifications for composite electrolytes are also investigated and discussed.It also summarizes the current concerns and obstacles that need to be broken through,as well as provides a basis guide for the selection and optimization of inorganic particles. 展开更多
关键词 Metal element substitutions Bimetallic inorganic particles Solid-state electrolytes All-solid-state lithium batteries MECHANISMS
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Effect of alkyl substitutions on self-assembly 被引量:1
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作者 Peng Wu Guojun Deng +4 位作者 Sailong Xu Qinghua Fan Lijun Wan Chen Wang Chunli Bai 《Chinese Science Bulletin》 SCIE EI CAS 2002年第18期1514-1517,共4页
The self-assemblies of 4-hexadecyloxybenzoic acid and 3,4,5-trihexadecyloxybenzoic acid have been studied by using scanning tunneling microscopy (STM). The well-ordered assemblies with different arrangement have been ... The self-assemblies of 4-hexadecyloxybenzoic acid and 3,4,5-trihexadecyloxybenzoic acid have been studied by using scanning tunneling microscopy (STM). The well-ordered assemblies with different arrangement have been investigated. The structural change is attributed to the different number of substituted alkyl chains on periphery. 展开更多
关键词 scanning TUNNELING MICROSCOPY (STM) SELF-ASSEMBLY ALKYL substitutions.
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Low band-gap benzodithiophene-thienothiophenecopolymers: the effect of dual two-dimensional substitutions on optoelectronic properties
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作者 Zhulin Liu Jiangman Sun +5 位作者 Yongxiang Zhu Peng Liu Lianjie Zhang Junwu Chen Fei Huang Yong Cao 《Science China Chemistry》 SCIE EI CAS CSCD 2015年第2期267-275,共9页
Two new conjugated copolymers, PBDT-T6-TTF and PBDT-T12-TTF, were derived from a novel 4-fluorobenzoyl thienothi- ophene (TTF). In addition, two types of benzodithiophene (BDT) units with 2,3-dihexylthienyl (T6)... Two new conjugated copolymers, PBDT-T6-TTF and PBDT-T12-TTF, were derived from a novel 4-fluorobenzoyl thienothi- ophene (TTF). In addition, two types of benzodithiophene (BDT) units with 2,3-dihexylthienyl (T6) and 2,3-didodecylthienyl (T12) substituents, respectively, were successfully synthesized. The effect of the dual two-dimensional (2D) substitutions of the building blocks upon the optoelectronic properties of the polymers was investigated. Generally, the two polymers exhibited good solubility and broad absorption, showing similar optical band gaps of ~1.53 eV. However, PBDT-T6-TTF with its shorter alkyl chain length possessed a larger extinction coefficient in thin solid film. The highest occupied molecular orbital (HOMO) level of PBDT-T6-TTF was located at -5.38 eV while that of PBDT-T12-TTF was at -5.51 eV. In space charge-limited- current (SCLC) measurement, PBDT-T6-TTF and PBDT-T12-TTF displayed respective hole mobilities of 3.0~10-~ and 1.6x10 5 cm2 V-1 s-l. In polymer solar cells, PBDT-T6-TTF and PBDT-T12-TTF showed respective power conversion efficiencies (PCEs) of 2.86% and 1.67%. When 1,8-diiodooctane (DIO) was used as the solvent additive, the PCE of PBDT-T6-TTF was remarkably elevated to 4.85%, but the use of DIO for the PBDT-T12-TTF-blend film resulted in a lower PCE of 0.91%. Atomic force microscopy (AFM) indicated that the superior efficiency of PBDT-T6-TTF with 3% DIO (v/v) should be related to the better continuous phase separation of the blend film. Nevertheless, the morphology of the PBDT-T12-TTF deteriorated when the 3% DIO (v/v) was added. Our results suggest that the alkyl-chain length on the 2D BDT units play an important role in determining the optoelectronic properties of dual 2D BDT-TT-based polymers. 展开更多
关键词 conjugated copolymers BENZODITHIOPHENE thienothiophene dual 2-dimentional substitutions alkyl side-chain length
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Explicit Substitutions: A Short Survey
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作者 Pierre-LoutsCurien 《Journal of Computer Science & Technology》 SCIE EI CSCD 1998年第6期562-563,共2页
关键词 A Short Survey Explicit substitutions
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A class of primitive substitutions and scrambled sets 被引量:7
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作者 LIAO GongFu FAN QinJie WANG LiDong 《Science China Mathematics》 SCIE 2008年第3期369-375,共7页
Consider the subshifts induced by constant-length primitive substitutions on two symbols. By investigating the equivalent version for the existence of Li-Yorke scrambled sets and by proving the non-existence of Schwei... Consider the subshifts induced by constant-length primitive substitutions on two symbols. By investigating the equivalent version for the existence of Li-Yorke scrambled sets and by proving the non-existence of Schweizer-Smítal scrambled sets, we completely reveal for this class of subshifts the chaotic behaviors possibly occurring in the sense of Li-Yorke and Schweizer-Smítal. 展开更多
关键词 primitive substitution SUBSHIFT Li-Yorke scrambled set Schweizer-Smítal scrambled set 54H20 58F03 58F08
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Some remarks on invertible substitutions on three letter alphabet 被引量:1
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作者 Zhixiong Wen Yiping Zhang 《Chinese Science Bulletin》 SCIE EI CAS 1999年第19期1755-1760,共6页
By introducing the notion of 'prime substitution' it is shown that the set of invertible substitutions over an alphabet of more than three letters is not finitely generated. Some examples are given.
关键词 invertible SUBSTITUTION PRIME substitution.
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First-principles study of multiple-site substitutions of alloying elements in Ni-based single crystal superalloys 被引量:2
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作者 SUN JunXi DU Wan +3 位作者 XIAO Bin WU YuQin LIU Yi ZHANG TongYi 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2021年第6期1276-1284,共9页
The development of Ni-based single crystal superalloys relies heavily on the composition design with the addition of critical alloying elements,e.g.,Re and Ru.Understanding the role of alloying effects require to know... The development of Ni-based single crystal superalloys relies heavily on the composition design with the addition of critical alloying elements,e.g.,Re and Ru.Understanding the role of alloying effects require to know the configurations of the alloying element distribution betweenγ-Ni andγ′-Ni3Al phases and among various non-equivalent sites.This work employed firstprinciples density functional theory calculations to study the preference of phase and site occupancy of 11 alloying elements including Al and transition metal elements:3d (Ti,Cr,Co,Ni),4d (Mo,Ru),and 5d (Hf,Ta,W,Re) in Ni and Ni3Al.We calculated the substitution energies of 1298 triple-site doping configurations including 286 Ni Ni Ni site doping of Ni,726 Al Ni Ni site doping,and 286 Ni Ni Ni site doping of Ni3Al with alloying elements Ni,Co,Ru,Cr,Re,Mo,W,Al,Ti,Ta,and Hf.In the dual-site and triple-site doping of Ni and Ni3Al,all studied alloying elements preferred to occupy Ni phase rather than Ni3Al phase.We found that the most stable defect complexes often contained the favorable substitutions of Al,Ti,Ta,and Hf for the Ni sites that stabilized the alloying elements doping at the other one or two nearest neighbor sites.The co-substitutions of various alloying elements at multiple sites are critical to understanding the strengthening mechanism of alloying elements in Ni-based single crystal superalloys. 展开更多
关键词 Ni-based single crystal superalloy first-principles density functional theory calculations phase and site occupancy substitution energy alloy design
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