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Research progress on electronic and active site engineering of cobalt‐based electrocatalysts for oxygen evolution reaction
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作者 Chuansheng He Linlin Yang +4 位作者 Jia Wang Tingting Wang Jian Ju Yizhong Lu Wei Chen 《Carbon Energy》 SCIE EI CAS CSCD 2024年第8期134-165,共32页
Electrocatalytic water splitting has been identified as a potential candidate for producing clean hydrogen energy with zero carbon emission.However,the sluggish kinetics of oxygen evolution reaction on the anode side ... Electrocatalytic water splitting has been identified as a potential candidate for producing clean hydrogen energy with zero carbon emission.However,the sluggish kinetics of oxygen evolution reaction on the anode side of the watersplitting device significantly hinders its practical applications.Generally,the efficiency of oxygen evolution processes depends greatly on the availability of cost‐effective catalysts with high activity and selectivity.In recent years,extensive theoretical and experimental studies have demonstrated that cobalt(Co)‐based nanomaterials,especially low‐dimensional Co‐based nanomaterials with a huge specific surface area and abundant unsaturated active sites,have emerged as versatile electrocatalysts for oxygen evolution reactions,and thus,great progress has been made in the rational design and synthesis of Co‐based nanomaterials for electrocatalytic oxygen evolution reactions.Considering the remarkable progress in this area,in this timely review,we highlight the most recent developments in Co‐based nanomaterials relating to their dimensional control,defect regulation(conductivity),electronic structure regulation,and so forth.Furthermore,a brief conclusion about recent progress achieved in oxygen evolution on Co‐based nanomaterials,as well as an outlook on future research challenges,is given. 展开更多
关键词 Co‐based nanomaterial dimension regulation electronic structure and active site oxygen evolution reaction
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Group Activities in Task-based Communicative Classroom 被引量:1
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作者 邓一琳 王宇澄 《新乡教育学院学报》 2005年第1期36-38,共3页
In a task-based communicative classroom, group activities are effective ways to devdop students' 4 basic language skills. However, not all group activities can reach the expected results. English teachers should p... In a task-based communicative classroom, group activities are effective ways to devdop students' 4 basic language skills. However, not all group activities can reach the expected results. English teachers should pay attention to some aspects in organizing a classroom group activity. 展开更多
关键词 GROUP activITY task-based LANGUAGE learning COMMUNICATIVE CLASSROOM
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Design of Task-Based Reading Activities in Reading Stages
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作者 Wu Haiping 《疯狂英语(理论版)》 2018年第4期58-59,65,共3页
In English reading, teachers should take students as the main body by creating situations, putting forward tasks,practicing interaction and evaluating teachers and students according to the corresponding classroom goa... In English reading, teachers should take students as the main body by creating situations, putting forward tasks,practicing interaction and evaluating teachers and students according to the corresponding classroom goals so as to improve students' English reading skills and the comprehensive use of language ability. Effective reading activities can help improve students' English level at different English reading stages,such as pre-reading stage,w hile-reading stage, post-reading stage. 展开更多
关键词 READING activities the task-based LANGUAGE TEACHING English READING STAGES
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CRISPR/Cas9-based gene activation and base editing in Populus
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作者 Tao Yao Guoliang Yuan +6 位作者 Haiwei Lu Yang Liu Jin Zhang Gerald A.Tuskan Wellington Muchero Jin-Gui Chen Xiaohan Yang 《Horticulture Research》 SCIE CSCD 2023年第6期205-213,共9页
The genus Populus has long been used for environmental,agroforestry and industrial applications worldwide.Today Populus is also recognized as a desirable crop for biofuel production and a model tree for physiological ... The genus Populus has long been used for environmental,agroforestry and industrial applications worldwide.Today Populus is also recognized as a desirable crop for biofuel production and a model tree for physiological and ecological research.As such,various modern biotechnologies,including CRISPR/Cas9-based techniques,have been actively applied to Populus for genetic and genomic improvements for traits such as increased growth rate and tailored lignin composition.However,CRISPR/Cas9 has been primarily used as the active Cas9 form to create knockouts in the hybrid poplar clone“717-1B4”(P.tremula x P.alba clone INRA 717-1B4).Alternative CRISPR/Cas9-based technologies,e.g.those involving modified Cas9 for gene activation and base editing,have not been evaluated in most Populus species for their efficacy.Here we employed a deactivated Cas9(dCas9)-based CRISPR activation(CRISPRa)technique to fine-tune the expression of two target genes,TPX2 and LecRLK-G which play important roles in plant growth and defense response,in hybrid poplar clone“717-1B4”and poplar clone“WV94”(P.deltoides“WV94”),respectively.We observed that CRISPRa resulted in 1.2-fold to 7.0-fold increase in target gene expression through transient expression in protoplasts and Agrobacterium-mediated stable transformation,demonstrating the effectiveness of dCas9-based CRISPRa system in Populus.In addition,we applied Cas9 nickase(nCas9)-based cytosine base editor(CBE)to precisely introduce premature stop codons via C-to-T conversion,with an efficiency of 13%–14%,in the target gene PLATZ which encodes a transcription factor involved in plant fungal pathogen response in hybrid poplar clone“717-1B4”.Overall,we showcase the successful application of CRISPR/Cas-based technologies in gene expression regulation and precise gene engineering in two Populus species,facilitating the adoption of emerging genome editing tools in woody species. 展开更多
关键词 CRISPR/Cas9 activATION base
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Synthesis, Characterization and Antibacterial Activities of Polydentate Schiff Bases, Based on Salicylaldehyde 被引量:1
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作者 Yosef Bayeh Fekiya Mohammed +3 位作者 Mamo Gebrezgiabher Fikre Elemo Mesfin Getachew Madhu Thomas 《Advances in Biological Chemistry》 2020年第5期127-139,共13页
<span style="font-family:Verdana;">Three Schiff bases L</span><sub><span style="font-family:Verdana;">1</span></sub><span style="font-family:Verdana;&quo... <span style="font-family:Verdana;">Three Schiff bases L</span><sub><span style="font-family:Verdana;">1</span></sub><span style="font-family:Verdana;">, L</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> and L</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;"> were synthesized by condensing salicylalde</span><span style="font-family:Verdana;">hyde with 4-aminoantipyrine, ethylendiamine and 2-aminophenol respec</span><span style="font-family:Verdana;">tively and subsequently characterized by various physicochemical investigations. All the three compounds were screened for their </span><i><span style="font-family:Verdana;">In-vitro</span></i><span style="font-family:Verdana;"> antibacterial activity against two gram positive bacteria, </span><i><span style="font-family:Verdana;">Staphylococcus aureus</span></i><span style="font-family:Verdana;"> (S.A), </span><i><span style="font-family:Verdana;">Staphylococcus epidermidis</span></i><span style="font-family:Verdana;"> (S.E) and two gram negative bacteria </span><i><span style="font-family:Verdana;">Klebsiella</span></i><span><span><i><span style="font-family:""> </span></i></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><i><span style="font-family:Verdana;">pneumoniae</span></i></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;"> (K.P) and </span><i><span style="font-family:Verdana;">Pseudomonas aeruginosa </span></i><span style="font-family:Verdana;">(</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">P.</span></span></span><span><span><span style="font-family:""><span style="font-family:Verdana;">A) by agar diffusion method. On comparing the results obtained with the activity of commercially available antibiotics such as Ciprofloxacin and Chloramphenicol, the newly synthesized compounds showed comparable antibacterial activities. The solvent methanol exhibit activity against all bacterial species with IZs ranging from 8 ± 0.25 to 17 ± 0.29 mm while the standard antibiotics Ciprofloxacin and Chloramphenicol exhibited an activities with IZs varying from 21.3 ± 0.31 to 28.3 ± 0.32 and 26.3 ± 0.24 mm to 32.3 ± 0.23 mm, respectively. However, the newly synthesized Schiff bases L</span><sub><span style="font-family:Verdana;">1</span></sub><span style="font-family:Verdana;">, L</span><sub><span style="font-family:Verdana;">2</span></sub><span style="font-family:Verdana;"> and L</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;"> showed IZs ranging from 7.4 ± 0.23 to 32.5 ± 0.14, 3 ± 0.57 to 12 ± 0.28 and 10 ± 0.20 to 32 ± 0.36 respectively. Among the Schiff bases, L</span><sub><span style="font-family:Verdana;">3</span></sub><span style="font-family:Verdana;"> showed the activity (32 ± 0.36) against S.E and P.A </span><span style="font-family:Verdana;">which is higher than the activity of standard antibiotics Ciprofloxacin and</span><span style="font-family:Verdana;"> Chloramphenicol against the same bacterial strains. The results obtained revealed that all the synthesized Schiff bases exhibit appreciable antibacterial activity against all the bacteria species which potentially makes them, to apply as wide range antibacterial drugs, after further </span><i><span style="font-family:Verdana;">in-vivo</span></i><span style="font-family:Verdana;"> cytotoxicity investigations. Their activity can also be further modified by changing the functionality of precursors for Schiff base condensation.</span></span></span></span> 展开更多
关键词 Schiff bases Salicyaldehyde Antibacterial activity In-Vitro
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Analysis of Activities of Adults with Aphasia at Community-Based Rehabilitation Training
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作者 Kiyoshi Nosu Ayuko Shigeta 《Journal of Biosciences and Medicines》 2015年第12期7-12,共6页
Aphasia is a higher brain dysfunction that affects the production or comprehension of speech and the ability to read or write. The purpose of this research is to establish support guidelines based on a questionnaire s... Aphasia is a higher brain dysfunction that affects the production or comprehension of speech and the ability to read or write. The purpose of this research is to establish support guidelines based on a questionnaire survey and a language activity analysis of rehabilitation training so that volunteers can more easily assist disabled persons with aphasia. The focus of this study was the non-profit community-based intervention group Yokohama Aphasia Partner Group, which consists of members with aphasia, their families, speech-language-and-hearing therapists, psychiatric social workers, and volunteers. The following results were obtained. (1) Members with aphasia participate in the Partner Group because they can meet others with aphasia on a regular basis as well as participate in the aphasia rehabilitation program with the recovery of language functions. In addition to medical treatment, the community-based support, which improves the environment and other life contextual factors, is important for rehabilitation. (2) An individual with aphasia shows different language actions, and so an individually different support system in accordance with language activity is necessary. 展开更多
关键词 APHASIA REHABILITATION Community-based-Support/Care Language activity
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An Empirical Study on Promoting Students’ Active Participation under“Task-based Teaching”in Adult ESL Classrooms
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作者 俞舒萌 《海外英语》 2019年第9期232-234,共3页
This paper focuses on a beginner adult ESL classroom aiming to enhance their participation under the guidance of“taskbased teaching”method. By incorporating three strategies of priming students to elicit their prior... This paper focuses on a beginner adult ESL classroom aiming to enhance their participation under the guidance of“taskbased teaching”method. By incorporating three strategies of priming students to elicit their prior knowledge on certain topic, designing a sequence of tasks to scaffold students for the final produce and modelling with lower level students to ensure their under? standing of task instructions, the activeness could see a significant increase. 展开更多
关键词 active participation student-center classroom PRIMING task-based TEACHING ESL TEACHING strategies
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Research on workflow meta model supporting activity based costing
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作者 周晓俊 曹建 《Journal of Southeast University(English Edition)》 EI CAS 2003年第4期324-330,共7页
Activity based costing (ABC) is a method which can solve many limitations of the traditional cost systems in manufacturing management. In this paper, we investigate how to integrate ABC with workflow technology, and ... Activity based costing (ABC) is a method which can solve many limitations of the traditional cost systems in manufacturing management. In this paper, we investigate how to integrate ABC with workflow technology, and build a workflow meta model supporting ABC. Firstly, the concept and concept model of activity based costing (ABC) are introduced. Next, the meta model of P -PROCE (Process, Product, Resource, Organization, and Cost & Evaluation) is presented. Then the cost meta model is defined by adding ABC to P -PROCE model. Object constraint language (OCL) is used to express meta model and constraints. Finally, we show an enterprise modeling and simulation tool based on the workflow meta model. We can systematically construct an enterprise model and easily and efficiently conduct simulation. Moreover it enables us to analyze and evaluate business processes and its costs. 展开更多
关键词 activity based costing WORKFLOW meta model object constraint language enterprise model
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Synthesis and Biological Activities of Some Mannich Bases of 5-(4-Hydroxyphenyl)-1,3,4-Oxadiazole-2-Thione
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作者 庞华 张君仁 +1 位作者 帅翔 王建河 《Journal of Chinese Pharmaceutical Sciences》 CAS 1998年第2期54-55,共2页
以对羟基苯甲酸乙酯为原料,经肼解、环化合成5(4羟基苯基)1,3,4二唑2硫酮,继而经Mannich反应合成了四种新曼尼希碱,其结构经红外光谱、核磁共振和元素分析证实。初步抑菌活性试验表明,显示弱的抑菌活性。
关键词 1 3 4-Oxadiazole-2-thione Mannich bases Biological activities
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Project-based Language Learning: an Activity Theory Analysis in SOE Language Learning
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作者 陈苡晴 《海外英语》 2016年第10期215-217,220,共4页
This study focuses on the effectiveness of the project-based language learning(PBLL) in a college Secretarial Oral English(SOE) Module. Student reflections of the language project work have been analyzed through Activ... This study focuses on the effectiveness of the project-based language learning(PBLL) in a college Secretarial Oral English(SOE) Module. Student reflections of the language project work have been analyzed through Activity Theory. Moreover,Data has been collected and categorized based on the components of complex human activity: the subject, object, tools(signs,symbols, and language), the community in which the activity take place, division of labor, and rules. The findings theoretically support the outcome of project-based language learning which align with the object of the activity. 展开更多
关键词 activITY THEORY PROJECT-based LEARNING SOE LANGUAGE LEARNING
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A Review on Theories of Task-based Teaching
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作者 谢济光 《科技信息》 2014年第10期24-24,39,共2页
Based on several books on English teaching and learning,this paper gives a general review on task-based teaching.Firstly,it introduces the definitions of task and task-based syllabus and makes two distinctions,namely,... Based on several books on English teaching and learning,this paper gives a general review on task-based teaching.Firstly,it introduces the definitions of task and task-based syllabus and makes two distinctions,namely,"task"and"activity","taskbased teaching"and"communicative teaching".Then it states the notions behind the task-based teaching.Finally,it gives the notes for the application of this approach. 展开更多
关键词 TASK activITY task-based TEACHING COMMUNICATIVE TE
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Syntheses, Crystal Structures and Antibacterial Activities of Schiff Base Ligand and Its Nickel(Ⅱ) Complex 被引量:5
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作者 李斐然 张欣 +2 位作者 王东东 薛志娜 马莺珂 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第9期1367-1374,共8页
A complex [NIL2] was synthesized, in which L, or to be exact, a Schiff base ligand (HL), was derived from the condensation of 1-phenyl-3-methyl-4-phenylacetyl-5-pyrazolone (PMPAP) with L-phenylalanine methyl ester... A complex [NIL2] was synthesized, in which L, or to be exact, a Schiff base ligand (HL), was derived from the condensation of 1-phenyl-3-methyl-4-phenylacetyl-5-pyrazolone (PMPAP) with L-phenylalanine methyl ester. They were characterized by IR and single-crystal X-ray diffraction. Green block crystals of both ligand and its complex were grown at room temperature. The ligand, which consists of two individual fragments, crystalizes in the P1 space group (a = 5.6268(5), b = 10.6892(11) and c = 19.4869(18) A). The complex crystalizes in the P21 space group (a -- 21.4076(18), b = 9.4792(8) and c = 25.287(2) A), which consists of a nickel six-coordinated compound. Every fragment is a distorted octahedron with four oxygen and two nitrogen atoms. The Schiff base ligand (HL) and its complex have been tested in vitro to evaluate their antibacterial activity against bacteria Escherichia Coli and Bacillus subtilis. It is found that the complex has higher activity than the corresponding free Schiff base ligand (HL) against the same bacterial. 展开更多
关键词 Schiff base COMPLEX crystal structure antibacterial activity
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Performance-based semi-active control algorithm for protecting base isolated buildings from near-fault earthquakes 被引量:3
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作者 Behnam Mehrparvar Taramarz Khoshnoudian 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2012年第1期43-55,共13页
Base isolated structures have been found to be at risk in near-fault regions as a result of long period pulses that may exist in near-source ground motions. Various control strategies, including passive, active and se... Base isolated structures have been found to be at risk in near-fault regions as a result of long period pulses that may exist in near-source ground motions. Various control strategies, including passive, active and semi-active control systems, have been investigated to overcome this problem. This study focuses on the development of a semi-active control algorithm based on several performance levels anticipated from an isolated building during different levels of ground shaking corresponding to various earthquake hazard levels. The proposed performance-based algorithm is based on a modified version of the well-known semi-active skyhook control algorithm. The proposed control algorithm changes the control gain depending on the level of shaking imposed on the structure. The proposed control system has been evaluated using a series of analyses performed on a base isolated benchmark building subjected to seven pairs of scaled ground motion records. Simulation results show that the newly proposed algorithm is effective in improving the structural and nonstructural performance of the building for selected earthquakes. 展开更多
关键词 structural control active control semi-active control base isolation
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Syntheses, Characterizations, Crystal Structures and Antibacterial Activities of Two Zinc(II) Complexes with a Schiff Base Derived from o-Vanillin and p-Toluidine 被引量:3
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作者 余玉叶 赵国良 温一航 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第12期1395-1402,共8页
Two new zinc(Ⅱ) complexes, [Zn2L2Ch].2[ZnL(CH3OH)Cl2] 1 and [ZnL2(NO3)2] 2, were synthesized by reacting ZnX2.nH2O (X = Cl^-, NO3^-) and a Schiff base ligand 2-[(4-methylphenylimino)methyl]-6-methoxyphenol ... Two new zinc(Ⅱ) complexes, [Zn2L2Ch].2[ZnL(CH3OH)Cl2] 1 and [ZnL2(NO3)2] 2, were synthesized by reacting ZnX2.nH2O (X = Cl^-, NO3^-) and a Schiff base ligand 2-[(4-methylphenylimino)methyl]-6-methoxyphenol (C15HIsNO2, L) which was obtained by the condensation of o-vanillin (2-hydroxy-3-methoxybenzaldehyde) with p-toluidine. Both 1 and 2 were characterized by single-crystal X-ray diffraction technique, elemental analysis, molar conductance, FT-IR, UV-Vis, IH-NMR spectra and thermogravimetrie analysis. The Schiff base ligand and its zinc(Ⅱ) complexes have been tested in vitro to evaluate their antibacterial activity against bacteria, viz., Escherichia Coli, Staphylococcus aureus and Bacillus Subtilis. The results show that these complexes have higher activity than the corresponding free Schiff base ligand against the same bacteria. 展开更多
关键词 O-VANILLIN P-TOLUIDINE Schiff base zinc(Ⅱ) complex crystal structure antibacterial activities
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Syntheses, Crystal Structures and Antibacterial Activities of Two Heterocyclic Schiff Base Compounds 被引量:2
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作者 杨高山 刘崇波 +3 位作者 李恒农 陈园 黄得和 温辉梁 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2014年第4期528-534,共7页
Two heterocyclic Schiff bases were synthesized via the condensation reactions of primary amines with carbonyl compounds. 2-[(4-pyridylmethylene)-amino] phenol (compound 1) was synthesized by the interaction of 4-p... Two heterocyclic Schiff bases were synthesized via the condensation reactions of primary amines with carbonyl compounds. 2-[(4-pyridylmethylene)-amino] phenol (compound 1) was synthesized by the interaction of 4-pyridinecarboxaldehyde with o-aminophenol in ethanol solvent; N,N'-bis(3-(furan-2-yl)allylidene)benzene-1,4-diamin (compound 2) was synthesized by the interaction of 3-(2-furyl)acrolein with p-phenylenediamine in ethanol medium. The compounds were characterized by elemental analysis, IR, MS and single-crystal X-ray diffraction. Compound 1 (C12H10N2O) crystallizes in the monoclinic system, space group P21/c with α = 7.0771(7), b = 7.2820(7), c = 19.849(2), b = 96.3390(10)°, V = 1016.66(17) ?3, Z = 4, Mr = 198.22, Dc = 1.295 g/cm3, F(000) = 416, GOOF = 1.060, m = 0.085 mm-1, the final R = 0.0371 and wR = 0.0929 for 1497 observed reflections with I 〉 2σ(I). Compound 2 (C20H16N2O2) crystallizes in the orthorhombic system, space group Fdd2 with α = 26.344(15), b = 48.50(3), c = 5.293(3), V = 6764(7) ?3, Z = 16, Mr = 316.35, Dc = 1.243 g/cm3, F(000) = 2656, GOOF = 1.043, m = 0.081 mm-1, the final R = 0.0526 and wR = 0.1267 for 2059 observed reflections with I 〉 2σ(I). 1 and 2 molecules are connected through hydrogen bonds to generate a 2D network and a 1D chain structure, respectively. The preliminary antibacterial activity results showed that the title compounds display excellent antibacterial activities to Escherichia coli, Staphylococcus aureus and Bacillus subtilis. 展开更多
关键词 HETEROCYCLIC Schiff bases synthesis crystal structure antibacterial activity
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Synthesis, Structure and Antibacterial Activities of 4-BBTS Schiff Base and Its Complexes 被引量:2
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作者 LI Pei-Fan LIU Bin WANG Jin-Ling 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第2期224-228,共5页
4-Bromobenzaldehyde thiosemicarbazone Schiff base (4-BBTS) and its Cu(Ⅱ), Zn(Ⅱ), Co(Ⅱ) and Ni(Ⅱ) complexes were synthesized and characterized by elemental analysis, UV, IR, MS, ^1H NMR, and molar conduct... 4-Bromobenzaldehyde thiosemicarbazone Schiff base (4-BBTS) and its Cu(Ⅱ), Zn(Ⅱ), Co(Ⅱ) and Ni(Ⅱ) complexes were synthesized and characterized by elemental analysis, UV, IR, MS, ^1H NMR, and molar conductivity. Using disc diffusion method, the antibacterial activity tests were conducted. The results revealed that the ligand as well as all the complexes exhibits good antibacterial activities against E. Coli. and S. Aureus. Moreover, Cu(Ⅱ) complex shows the best antibacterial activity, which provides beneficial reference for studying the relationship between the structures and performances. 展开更多
关键词 4-BBTS Schiff base SYNTHESIS STRUCTURE antibacterial activity
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Synthesis, Characterization and Biological Activity Evaluation of Schiff Bases Derived from 1,8-Diaminonaphtalène
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作者 Niameke Jean Baptiste Kangah Nanou Tiéba Tuo +4 位作者 Daouda Ballo Ahmont Landry Claude Kablan N’goran Etienne Kouame Charles Guillaume Kodjo Nahossé Ziao 《Open Journal of Physical Chemistry》 CAS 2023年第2期29-37,共9页
The compounds have been synthesized and characterized by routine MS, IR and NMR spectrometry methods. The compounds are all active on bacterial strains with the exception of Salmonella typhimirium, with a MIC value of... The compounds have been synthesized and characterized by routine MS, IR and NMR spectrometry methods. The compounds are all active on bacterial strains with the exception of Salmonella typhimirium, with a MIC value of 7.5 mg/mL. They show a percentage of anti-radical activity of 75.476 ± 5.070 for the compound DAN-S and of 68.142 ± 6.539 for the compound DAN-OV. The compounds are sensitive to the two champions used. DAN-S compound is then the most active. 展开更多
关键词 Schiff base SPECTROMETRY ANTIOXIDANT Antimicrobial activity INHIBITION 1 8-Diaminonaphthalene
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Carbon‐based metal‐free catalysts for electrochemical CO2 reduction: Activity, selectivity, and stability 被引量:10
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作者 Israr Masood ul Hasan Luwei Peng +5 位作者 Jianfeng Mao Ruiman He Yongxia Wang Jing Fu Nengneng Xu Jinli Qiao 《Carbon Energy》 CAS 2021年第1期24-49,共26页
Zero or negative emissions of carbon dioxide(CO2)is the need of the times,as inexorable rising and alarming levels of CO2 in the atmosphere lead to global warming and severe climate change.The electrochemical CO2 redu... Zero or negative emissions of carbon dioxide(CO2)is the need of the times,as inexorable rising and alarming levels of CO2 in the atmosphere lead to global warming and severe climate change.The electrochemical CO2 reduction(eCO2R)to value‐added fuels and chemicals by using renewable electricity provides a cleaner and more sustainable route with economic benefits,in which the key is to develop clean and economical electrocatalysts.Carbon‐based catalyst materials possess desirable properties such as high offset potential for H2 evolution and chemical stability at the negative applied potential.Although it is still challenging to achieve highly efficient carbon‐based catalysts,considerable efforts have been devoted to overcoming the low selectivity,activity,and stability.Here,we summarize and discuss the recent progress in carbon‐based metal‐free catalysts including carbon nanotubes,carbon nanofibers,carbon nanoribbons,graphene,carbon nitride,and diamonds with an emphasis on their activity,product selectivity,and stability.In addition,the key challenges and future potential approaches for efficient eCO2R to low carbon‐based fuels are highlighted.For a good understanding of the whole history of the development of eCO2R,the CO2 reduction reactions,principles,and techniques including the role of electrolytes,electrochemical cell design and evaluation,product selectivity,and structural composition are also discussed.The metal/metal oxides decorated with carbon‐based electrocatalysts are also summarized.We aim to provide insights for further development of carbon‐based metal‐free electrocatalysts for CO2 reduction from the perspective of both fundamental understanding and technological applications in the future. 展开更多
关键词 activITY carbon‐based catalyst CO2 electrochemical reduction SELECTIVITY STABILITY
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Electrochemical Performance of Nickel Hydroxide/Activated Carbon Supercapacitors Using a Modified Polyvinyl Alcohol Based Alkaline Polymer Electrolyte 被引量:3
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作者 孙紫红 袁安保 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2009年第1期150-155,共6页
Polyvinyl alcohol (PVA)-sodium polyacrylate (PAAS)-KOH-H2O alkaline polymer electrolyte film with high ionic conductivity was prepared by a solution-casting method. Polymer Ni(OH)2/activated carbon (AC) hybrid... Polyvinyl alcohol (PVA)-sodium polyacrylate (PAAS)-KOH-H2O alkaline polymer electrolyte film with high ionic conductivity was prepared by a solution-casting method. Polymer Ni(OH)2/activated carbon (AC) hybrid supercapacitors with different electrode active material mass ratios (positive to negative) were fabricated using this alkaline polymer electrolyte, nickel hydroxide positive electrodes, and AC negative electrodes. Galvanostatic charge/ discharge and electrochemical impedance spectroscopy (EIS) methods were used to study the electrochemical performance of the capacitors, such as charge/discharge specific capacitance, rate charge/discharge ability, and charge/discharge cyclic stability. Experimental results showed that with the decreasing of active material mass ratio m(Ni(OH)2)/m(AC), the charge/discharge specific capacitance increases, but the rate charge/discharge ability and the charge/discharge cyclic stability decrease. 展开更多
关键词 PVA based alkaline polymer electrolyte Ni(OH)2/AC supercapacitor electrode active material mass ratio electrochemical performance
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Biological Activities of Schiff Bases and Their Complexes: A Review of Recent Works 被引量:1
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作者 Wail Al Zoubi 《International Journal of Organic Chemistry》 2013年第3期73-95,共23页
Schiff bases are the most widely used organic compounds. They have been shown to exhibit a broad range of biological activities, including antifungal, antibacterial, antimalarial, antiproliferative, anti-inflammatory,... Schiff bases are the most widely used organic compounds. They have been shown to exhibit a broad range of biological activities, including antifungal, antibacterial, antimalarial, antiproliferative, anti-inflammatory, antiviral, and antipyretic properties. This review summarizes the synthesis and biological activities of Schiff bases and their complexes. 展开更多
关键词 SCHIFF baseS Metal COMPLEXES ANTIBACTERIAL BIOLOGICAL activities
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