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建立α与β珠蛋白基因簇转基因鼠模型及β基因族反式因子研究
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作者 刘德培 梁植权 +14 位作者 黄粤 冯东晓 纪新军 吴林 徐冬冬 李政 唐晓彬 李铁昌 吴敏 詹惠春 李兴国 吕湘 李磊 沈伟 唐毅 《医学研究通讯》 2003年第6期18-19,共2页
随着人类功能基因组研究的广泛开展,理解基因组中的遗传信息如何协调、有序地调控细胞分化与个体发育的时空过程成为研究的基本问题,阐明这一机制是真核基因表达调控研究的根本任务.
关键词 β珠蛋白基因簇 α珠蛋白基因簇 转基因鼠 β基因式因子
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中国反颚茧蜂族(膜翅目:茧蜂科:反颚茧蜂亚科)的物种名录,区系分布及寄主
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作者 方舒倩 赵庆燕 +2 位作者 李吉敏 王灵敏 姚俊丽 《武夷科学》 2022年第2期134-148,共15页
反颚茧蜂族(Alysiini)是一类重要的寄生性昆虫,世界广布。截至2022年11月,中国反颚茧蜂族有31属248种,分别占世界已知属和种的39.24%、14.87%。中国反颚茧蜂族特有种92种,占中国反颚茧蜂族种数的37.10%。中国地跨古北界和东洋界,本文研... 反颚茧蜂族(Alysiini)是一类重要的寄生性昆虫,世界广布。截至2022年11月,中国反颚茧蜂族有31属248种,分别占世界已知属和种的39.24%、14.87%。中国反颚茧蜂族特有种92种,占中国反颚茧蜂族种数的37.10%。中国地跨古北界和东洋界,本文研究了中国反颚茧蜂族的地理分布,发现反颚茧蜂族分布以古北界和东洋界共有属级分布型最丰富,有15属51种;其次为东洋界特有分布型,有11属114种;而古北界特有分布型仅5属,但种类丰富,有83种。据统计,中国反颚茧蜂族已知昆虫寄主有5目49科137属,对其应用于害虫生物防治意义重大。 展开更多
关键词 膜翅目 颚茧蜂 生物多样性 区系分布 寄主
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反潮族
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作者 郑丽 《中学生英语(上旬刊)》 2011年第12期22-22,共1页
反潮族是指反潮流的新族类,他们的生活作派和对待工作思路.好像是和现实反着干,可真正走进他们的世界,会发现,反潮流其实也是理念更新的一种快乐生活方式.他们的生活也有它不同寻常的真谛。
关键词 英语学习 初中英语 英语美文 英语阅读
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云南民间制陶技术的调查研究 被引量:10
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作者 杨莉 《中央民族大学学报(哲学社会科学版)》 CSSCI 北大核心 2002年第3期35-39,共5页
制陶是人类普遍的造物活动。云南的一些少数民族至今还保留了较为原始的制陶工具及制陶方法 。
关键词 云南 少数民 民间制陶技术 调查研究 反族 学术价值
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Effects of the Amino Acids of Aspartate Family on the Biosynthesis of CoQ_(10) in Rhodopseudomonas palustris J001 被引量:1
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作者 蒋世云 余龙江 《Agricultural Science & Technology》 CAS 2008年第4期1-3,13,共4页
[Objective]The study aimed to investigate the effects of the amino acids of aspartate family on the biosynthesis of CoQ10 in Rhodpseudomonas palustris J001.[Method]The impacts of amino acids of this family on the bios... [Objective]The study aimed to investigate the effects of the amino acids of aspartate family on the biosynthesis of CoQ10 in Rhodpseudomonas palustris J001.[Method]The impacts of amino acids of this family on the biosynthesis of CoQ10 in Rhodopseudomnas palustris J001 were investigated by feeding these amino acids at the end of the logarithmic phase during incubation,which aim was for the optimization of the fermentation medium and genetic improvement of the strain for CoQ10 production.[Result]The results showed that feeding proper amount of methione(125 mg/L)could increase CoQ10 production by 20.2%,but feeding of lysine(above 500 mg/L),threonine(above 400 mg/L)and/or isoleucine(above 400 mg/L)repressed the biosynthesis of CoQ10.The results indicated that the aspartate kinase is subject to feedback inhibition or repression by lysine,threonine and isoleucine in the strain,which was unfavorable to the formation of methioine and then caused the decrease of CoQ10 production.[Conclusion]Lysine,threonine and isoleucine auxotrophic mutants with resistance to analogues of lysine,threonine and isoleucine could increase the production of CoQ10. 展开更多
关键词 CoQ10 Amino acids of aspartate family Feedback inhibition Rhodopseudomnas palustris
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Interfacial reactions between Sn-2.5Ag-2.0Ni solder and electroless Ni(P) deposited on SiC_p/Al composites 被引量:3
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作者 吴茂 曲选辉 +3 位作者 何新波 Rafi-ud-din 任淑彬 秦明礼 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第6期958-965,共8页
A novel Sn-2.5Ag-2.0Ni alloy was used for soldering SiCp/Al composites substrate deposited with electroless Ni(5%P) (mass fraction)and Ni(10%P)(mass fraction)layers.It is observed that variation of P contents in the e... A novel Sn-2.5Ag-2.0Ni alloy was used for soldering SiCp/Al composites substrate deposited with electroless Ni(5%P) (mass fraction)and Ni(10%P)(mass fraction)layers.It is observed that variation of P contents in the electroless Ni(P)layer results in different types of microstructures of SnAgNi/Ni(P)solder joint.The morphology of Ni3Sn4 intermetallic compounds(IMCs)formed between the solder and Ni(10%P)layer is observed to be needle-like and this shape provides high speed diffusion channels for Ni to diffuse into solder that culminates in high growth rate of Ni3Sn4.The diffusion of Ni into solder furthermore results in the formation of Kirkendall voids at the interface of Ni(P)layer and SiCp/Al composites substrate.It is observed that solder reliability is degraded by the formation of Ni2SnP,P rich Ni layer and Kirkendall voids.The compact Ni3Sn4 IMC layer in Ni(5%P)solder joint prevents Ni element from diffusing into solder,resulting in a low growth rate of Ni3Sn4 layer.Meanwhile,the formation of Ni2SnP that significantly affects the reliability of solder joints is suppressed by the low P content Ni(5%P)layer.Thus,shear strength of Ni(5%P) solder joint is concluded to be higher than that of Ni(10%P)solder joint.Growth of Ni3Sn4 IMC layer and formation of crack are accounted to be the major sources of the failure of Ni(5%P)solder joint. 展开更多
关键词 SnAgNi solder electroless Ni(P) SiCp/Al composites intermetallic compound interfacial reaction
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Mechanochemical Reaction of Aromatic Ketones and Aldehydes in the Presence of Zn-ZnCl_2
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作者 GuanWuWANG LuLIU 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第5期587-590,共4页
The solvent-free reactions of aromatic ketones and aldehydes in the presence of Zn-ZnCl2 were performed with the aid of high-speed vibration mill, Retsch MM200 mixer mill and Retsch RM100 mortar grinder to give pinaco... The solvent-free reactions of aromatic ketones and aldehydes in the presence of Zn-ZnCl2 were performed with the aid of high-speed vibration mill, Retsch MM200 mixer mill and Retsch RM100 mortar grinder to give pinacol coupling and reduction products in varying yields. 展开更多
关键词 Pinacol coupling solvent-free reaction aromatic ketones aromatic aldehydes mechanochemical reaction.
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Close Coupled Showerhead Reactors for the Growth of Group Ⅲ Nitrides
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作者 Thrush E J Kappers M +5 位作者 Considine L Mullins J T Saywell V Bentham F C Sharma N Humphreys C J 《发光学报》 EI CAS CSCD 北大核心 2001年第z1期103-106,共4页
The group Ⅲ nitrides are an important class of materials with aplications in UV and visible optoelectronics,high temperature electronics,cold cathodes and solar blind detectors.In recent years,with the realisation of... The group Ⅲ nitrides are an important class of materials with aplications in UV and visible optoelectronics,high temperature electronics,cold cathodes and solar blind detectors.In recent years,with the realisation of nitride based LEDs,the use of GaN IED has the potential to compete with 1raditional filament and discharge lamps,for the provision of white lighting,and there has been an explosion of interest in the MOCVD growth of GaN based materials with an increasing focus on large area multiwafer reactors and wafer uniforrmity.This paper will review the design philosophy and characteristics of close-coupled showerhead reactors,relating these to the requirements of group Ⅲ-nitride growth,and will present a selection of data resulting from the operation of such equipment.These results suggest that the close coupled showerhead style of reactor is very suitable for the growth of GaN based structures in both research and production environments. 展开更多
关键词 MOCVD close coupled showerhead reactor growth of groupⅢnitrides
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“反潮族”的自我生活
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《Women of China》 2012年第1期77-77,共1页
手写信传纸质图书…在数字横行的今天,偶尔做下“反潮族”也是不错的体验。
关键词 "" 生活 信件 图书
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Construction of prokaryotic expression system of TGF-β1 epitope gene and identification of recombinant fusion protein immunity 被引量:3
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作者 Yong-Hong Guo Zhi-Ming Hao +1 位作者 Jin-Yan Luo Jun-Hong Wang 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第40期6389-6394,共6页
AIM: To insert the constructed TGF-β1 epitope gene into the el loop of C-terminus of truncated hepatitis B core antigen to increase TGF-β1 antigenicity in its prokaryotic expression system and to identify immunity ... AIM: To insert the constructed TGF-β1 epitope gene into the el loop of C-terminus of truncated hepatitis B core antigen to increase TGF-β1 antigenicity in its prokaryotic expression system and to identify immunity of the expressed recombinant protein in order to exploit the possibility for obtaining anti- TGF-β1 vaccine. METHODS: The TGF-β1 encoding epitope gene (the mature TGF-β1 from 78-109 amino acid residues, TGF-β1^32) was amplified by polymerase chain reaction from the recombinant pGEM-7z/ TGF-β1 ^32 vector. The HBcAg gene fragments (encoding HBcAg from 1-71 and 89-144 amino acid residues) were amplified from PYTAI- HBcAg vector. The recombinant vector pGEMEX-1 was used to insert HBcAg1-71, TGF-β1^32 and HBcAg89-144 into restrictive endonuclease enzyme and ligated with T4 Ugase. The fusion gene fragments HBc.Ag1-71-TGF-β1^32 HBcAg89-144 were recloned to pET28a(+) and the DNA sequence was confirmed by the dideoxy chain termination method. The recombinant vector pET28a (+)/ CTC was transformed and expressed in E. coli BL21 (DE3) under induction of IPTG. After purification with Ni^+2 NTA agarose resins, the antigenicity of purified protein was detected by ELISA and Western blot and visualized under electron microscope. RESULTS: Enzyme digestion analysis and sequencing showed that TGF-β1 epitope gene was inserted into the el loop of C-terminus of truncated hepatitis B core antigen. SDS-PAGE analysis showed that relative molecular mass (Mr) of the expressed product by pET28a (+)/CTC was Mr 24 600.The output of the target recombinant protein was approximately 34.8% of the total bacterial protein,mainly presented in the form of inclusion body. Western blotting and ELISA demonstrated that the fusion protein could combine with anti-TGF-β1 polyclonal IgG but not with anti-HBcAg. The purity of protein was about 90 % and the protein was in the form of self-assembling particles visualized under electron microscope. This fusion protein had good anti-TGF-β1 antigenicity and could be used as anti-TGF-β1 vaccine. CONCLUSION: A recombinant prokaryotic expression system with high expression efficiency of the target TGF-β1 epitope gene was successfully established. The fusion protein is in the form of self-assembling particles and HBcAg can increase the antigenicity of TGF-β1. The expressed TGF-β1 epitope gene shows good immunogenicity and antigenicity. 展开更多
关键词 Prokaryotic expression system TGF-β1 epitope IMMUNOGENICITY ANTIGENICITY
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Incidence of gastroesophageal reflux disease in Uygur and Han Chinese adults in Urumqi 被引量:17
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作者 Chun-Yan Niu Yong-Li Zhou +4 位作者 Rong Yan Ni-La Mu Bao-Hua Gao Fang-Xiong Wu Jin-Yan Luo 《World Journal of Gastroenterology》 SCIE CAS CSCD 2012年第48期7333-7340,共8页
AIM:To investigate the incidence of gastroesophageal reflux disease(GERD) and its related risk factors in Uygur and Han Chinese adult in Urumqi,China.METHODS:A population-based cross-sectional survey was undertaken in... AIM:To investigate the incidence of gastroesophageal reflux disease(GERD) and its related risk factors in Uygur and Han Chinese adult in Urumqi,China.METHODS:A population-based cross-sectional survey was undertaken in a total of 972 Uygur(684 male and 288 female) aged from 24 to 61 and 1023 Han Chinese(752 male and 271 female) aged from 23 to 63 years.All participants were recruited from the residents who visited hospital for health examination from November 2011 to May 2012.Each participant signed an informed consent and completed a GERD questionnaire(GerdQ) and a lifestyle-food frequency questionnaire survey.Participants whose Gerd Q score was ≥ 8 and met one of the following requirements would be enrolled into this research:(1) being diagnosed with erosive esophagitis(EE) or Barrett's esophagus(BE) by endoscopy;(2) negative manifestation under endoscopy(non-erosive reflux disease,NERD) with abnormal acid reflux revealed by 24-h esophageal pH monitoring;and(3) suffering from typical heartburn and regurgitation with positive result of proton pump inhibitor test.RESULTS:According to Gerd Q scoring criteria,340 cases of Uygur and 286 cases of Han Chinese were defined as GERD.GERD incidence in Uygur was significantly higher than in Han Chinese(35% vs 28%,χ2 = 11.09,P < 0.005),Gerd Q score in Uygur was higher than in Han Chinese(7.85 ± 3.1 vs 7.15 ± 2.9,P < 0.005),and Gerd Q total score in Uygur male was higher than in female(8.15 ± 2.8 vs 6.85 ± 2.5,P < 0.005).According to normalized methods,304(31%) cases of Uygur were diagnosed with GERD,including 89 cases of EE,185 cases of NERD and 30 cases of BE;256(25%) cases of Han Chinese were diagnosed with GERD,including 90 cases of EE,140 cases of NERD and 26 cases of BE.GERD incidence in Uygur was significantly higher than in Han Chinese(31% vs 25%,χ2 = 9.34,P < 0.005) while the incidences were higher in males of both groups than in females(26% vs 5% in Uygur,χ2 = 35.95,P < 0.005,and 19.8% vs 5.2% in Han,χ2 = 5.48,P < 0.025).GERD incidence in Uygur male was higher than in Han Chinese male(26% vs 19.8%,χ2 = 16.51,P < 0.005),and incidence of NERD in Uygur was higher than in Han Chinese(χ2 = 10.06,P < 0.005).Occupation(r = 0.623),gender(r = 0.839),smoking(r = 0.322),strong tea(r = 0.658),alcohol drinking(r = 0.696),meat-based diet(mainly meat)(r = 0.676) and body mass index(BMI)(r = 0.567) were linearly correlated with GERD in Uygur(r = 0.833,P = 0.000);while gender(r = 0.957),age(r = 0.016),occupation(r = 0.482),strong tea(r = 1.124),alcohol drinking(r = 0.558),meat diet(r = 0.591) and BMI(r = 0.246) were linearly correlated with GERD in Han Chinese(r = 0.786,P = 0.01).There was no significant difference between Gerd Q scoring and three normalized methods for the diagnosis of GERD.CONCLUSION:GERD is highly prevalent in adult in Urumqi,especially in Uygur.Male,civil servant,smoking,strong tea,alcohol drinking,meat diet and BMI are risk factors correlated to GERD. 展开更多
关键词 Gastroesophageal reflux disease Incidence Uygur Han Risk factors Urumqi
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Family Firms and the Market Reaction to Dividend News
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作者 Elisabete F Simoes Vieira 《Journal of Modern Accounting and Auditing》 2013年第4期527-541,共15页
This paper provides an analysis of the market reaction to dividend change announcements for publicly-traded, family-controlled firms. Family firms have a significantly lower proportion of independent directors than no... This paper provides an analysis of the market reaction to dividend change announcements for publicly-traded, family-controlled firms. Family firms have a significantly lower proportion of independent directors than non-family firms, which is consistent with the idea that family members dominate the board of directors and that family shareholders are common in publicly-traded firms. The author analyzed 390 dividend change announcements in Portugal over the period from 1991 to 2010 using a panel data approach. The results show no evidence of a significant market reaction to dividend change announcements, providing no evidence in support of the dividend-signaling hypothesis in the context of family firms. This conclusion agrees with previous studies in which there was no distinction between family and non-family firms. Empirical results show that family firms engage in lower payouts than their non-family counterparts, giving some supports to the expropriation hypothesis. This finding may indicate that families expropriate the wealth of shareholders through lower dividends. This result is also consistent with the clientele theory of dividends. 展开更多
关键词 family firms cash dividends signaling hypothesis market reaction
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中国近波贝茧蜂属新纪录及一新种记述(膜翅目,茧蜂科)(英文) 被引量:1
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作者 郑敏琳 陈家骅 杨建全 《动物分类学报》 CSCD 北大核心 2013年第1期143-146,共4页
记述采自中国湖北的近波贝茧蜂属Bobekoides van Achterberg1新种,中华近波贝茧蜂B.sinicus sp.nov.。文中对近波贝茧蜂属及新种进行了详细的描述,编制了该属世界已知种的检索表,新种附有鉴别形态特征图,并与其近似种作了比较。新种模... 记述采自中国湖北的近波贝茧蜂属Bobekoides van Achterberg1新种,中华近波贝茧蜂B.sinicus sp.nov.。文中对近波贝茧蜂属及新种进行了详细的描述,编制了该属世界已知种的检索表,新种附有鉴别形态特征图,并与其近似种作了比较。新种模式标本保存于福建农林大学益虫研究所。 展开更多
关键词 膜翅目 茧蜂科 颚茧蜂亚科 颚茧蜂 近波贝茧蜂属 新种 中国
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Resourceability on nuclear fuel cycle by transmutation approach 被引量:2
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作者 OZAWA Masaki SAITO Masaki 《Science China Chemistry》 SCIE EI CAS 2012年第9期1746-1751,共6页
A resourceability on nuclear fuel cycle by transmutation of fission products in the spent fuel of nuclear reactors is discussed in this paper to investigate the feasibility of "creation and utilization" of Apr6s ORI... A resourceability on nuclear fuel cycle by transmutation of fission products in the spent fuel of nuclear reactors is discussed in this paper to investigate the feasibility of "creation and utilization" of Apr6s ORIENT from Adv.-ORIENT cycle, in which chemical "separation and utilization" of nuclear rare metals (platinum group metals, Mo, Tc, rare earth, etc.) has been proposed since FY2006. Apr6s ORIENT research program was newly initiated in FY2011 for nuclear transmutation of fission products into stable or short-lived highly-valuable elements. In the resourceability of rare earth metals from fission products, non-radioactive Nd and Dy can be created from Pr and Tb, respectively, by transmutation. Especially, the Dy creation has relatively high feasibility of about 10-20 %/y in creation rate. A proper moderation of neutrons in blanket of fast reactors may be required to provide a high creation rate of La from Ba. In light platinum group metals, non-radioactive Ru can be created from Tc by transmutation, of which creation rate is about 4-5 %/y in blanket of fast reactors. Pd created from Rh is almost non-radioactively depending on the isotope fraction of 107pd. Rh creation from Ru is not feasible under the neutron irradiation of typical nuclear reactors. 展开更多
关键词 Apres ORIENT Advanced ORIENT cycle nuclear rare metal TRANSMUTATION nuclear fuel cycle
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Diverse roles of SERK family genes in plant growth, development and defense response. 被引量:7
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作者 Min Fan Minmin Wang Ming-Yi Bai 《Science China(Life Sciences)》 SCIE CAS CSCD 2016年第9期889-896,共8页
Plant receptor-like protein kinases(RLKs) are transmembrane proteins with an extracellular domain and an intracellular kinase domain, which enable plant perceiving diverse extracellular stimuli to trigger the intracel... Plant receptor-like protein kinases(RLKs) are transmembrane proteins with an extracellular domain and an intracellular kinase domain, which enable plant perceiving diverse extracellular stimuli to trigger the intracellular signal transduction. The somatic embryogenesis receptor kinases(SERKs) code the leucine-rich-repeat receptor-like kinase(LRR-RLK), and have been demonstrated to associate with multiple ligand-binding receptors to regulate plant growth, root development, male fertility, stomatal development and movement, and immune responses. Here, we focus on the progress made in recent years in understanding the versatile functions of Arabidopsis SERK proteins, and review SERK proteins as co-receptor to perceive different endogenous and environmental cues in different signaling pathway, and discuss how the kinase activity of SERKs is regulated by various modification. 展开更多
关键词 RLK SERK signal transduction
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Engineering two-dimensional metal oxides and chalcogenides for enhanced electro-and photocatalysis 被引量:6
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作者 Yichao Wang Baiyu Ren +4 位作者 Jian Zhen Ou Kai Xu Chunhui Yang Yongxiang Li Haijiao Zhang 《Science Bulletin》 SCIE EI CSCD 2021年第12期1228-1252,M0004,共26页
Two-dimensional(2D)metal oxides and chalcogenides(MOs&MCs)have been regarded as a new class of promising electro-and photocatalysts for many important chemical reactions such as hydrogen evolution reaction,CO_(2) ... Two-dimensional(2D)metal oxides and chalcogenides(MOs&MCs)have been regarded as a new class of promising electro-and photocatalysts for many important chemical reactions such as hydrogen evolution reaction,CO_(2) reduction reaction and N2 reduction reaction in virtue of their outstanding physicochemical properties.However,pristine 2D MOs&MCs generally show the relatively poor catalytic performances due to the low electrical conductivity,few active sites and fast charge recombination.Therefore,considerable efforts have been devoted to engineering 2D MOs&MCs by rational structural design and chemical modification to further improve the catalytic activities.Herein,we comprehensively review the recent advances for engineering technologies of 2D MOs&MCs,which are mainly focused on the intercalation,doping,defects creation,facet design and compositing with functional materials.Meanwhile,the relationship between morphological,physicochemical,electronic,and optical properties of 2D MOs&MCs and their electro-and photocatalytic performances is also systematically discussed.Finally,we further give the prospect and challenge of the field and possible future research directions,aiming to inspire more research for achieving high-performance 2D MOs&MCs catalysts in energy storage and conversion fields. 展开更多
关键词 Two-dimensional materials Metal oxides Metal chalcogenides ELECTROCATALYSIS PHOTOCATALYSIS
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Theoretical insights into the [4+2]/retro [4+2] cycloaddition approach to the synthesis of biaryls and polycyclic aromatics
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作者 LI XinYao XU JiaXi 《Science China Chemistry》 SCIE EI CAS 2013年第5期633-640,共8页
A domino [4+2]/retro [4+2] cycloaddition process of cyclohexadienes with arylethynes or benzyne providing access to biaryls and polycyclic aromatics has been studied theoretically using density functional theory calcu... A domino [4+2]/retro [4+2] cycloaddition process of cyclohexadienes with arylethynes or benzyne providing access to biaryls and polycyclic aromatics has been studied theoretically using density functional theory calculations. It has been found that the initial Diels-Alder (D-A) reaction acts as the rate-determining step and the consequent [4+2] cycloreversion reaction is feasible under the conditions used. Furthermore, the D-A reaction affects the regioselectivity, the origin of which is essentially derived from the good match of orbital coefficients between dienes and dienophiles as shown by using frontier molecular orbital (FMO) theory. Further investigation of the reactivity reveals that the reactions are predicted to fail to occur if an electron-donor group in the diene or an electron-acceptor group in the dienophile is lacking, as a consequence of the increased FMO energy gap. By further exploring the scope of substrates computationally, benzyne as an active dienophile was predicted to react with a variety of dienes in a cascade reaction under mild conditions with a low energy barrier, with the rate-determining step being the retro [4+2] cycloaddition. 展开更多
关键词 [4+2]/retro [4+2] cycloaddition BIARYLS polycyclic aromatics regioselectivity DFT study
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