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Commentary on“Association of accelerometer-measured sleep duration and different intensities of physical activity with incident type 2 diabetes in a population-based cohort study”
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作者 Barbara E.Ainsworth Haili Tian 《Journal of Sport and Health Science》 2025年第2期75-76,共2页
Type 2 diabetes(T2D)is a global public health issue.In 2021,537 million adults were diagnosed with T2D,corresponding to 10.5%of adults aged 20 and older.^(1)T2D increases the risks for morbidity,disability,and prematu... Type 2 diabetes(T2D)is a global public health issue.In 2021,537 million adults were diagnosed with T2D,corresponding to 10.5%of adults aged 20 and older.^(1)T2D increases the risks for morbidity,disability,and premature mortality,which increased by 3%between 2000 and 2019.2 Evidence is strong that maintaining a healthy diet,engaging in regular physical activity(PA),and preventing obesity can prevent or delay the incidence of T2D. 展开更多
关键词 public health issue population based cohort study ACCELEROMETER physical activity type diabetes t d preventing obesity sleep duration type diabetes
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Correction to: Improved thermoelectric properties of zone-melted p-type bismuth-telluride-based alloys for power generation
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作者 Ren-Shuang Zhai Tie-Jun Zhu 《Rare Metals》 2025年第4期2870-2870,共1页
In the original publication,mistakenly first and corresponding affiliation is given as:Thermoelectricity Technology Center,Hangzhou Dahe Thermo-Magnetics Co.Ltd,Hangzhou 310053,ChinaThe correct first and corresponding... In the original publication,mistakenly first and corresponding affiliation is given as:Thermoelectricity Technology Center,Hangzhou Dahe Thermo-Magnetics Co.Ltd,Hangzhou 310053,ChinaThe correct first and corresponding affiliation is:State Key Laboratory of Silicon Materials,School of Materials Science and Engineering,Zhejiang University,Hangzhou 310027,China. 展开更多
关键词 thermoelectric properties power generation silicon materialsschool p type bismuth telluride based alloys zone melting
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New Insights into the Depositional Environments of Ordovician Carbonate Formations in the Yubei Area of Tarim Basin Based on Standard Microfacies Types 被引量:6
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作者 HUANG Chenjun LIU Geyun +3 位作者 MA Yongsheng LIU Bo LIU Hongguang SHI Kaibo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第2期755-756,共2页
Objective The Yubei area is located in the mid-east Maigaiti slope of southwestern Tarim Basin, China, with an exploration history of several years. Recent exploration has preliminarily indicated that the Ordovician ... Objective The Yubei area is located in the mid-east Maigaiti slope of southwestern Tarim Basin, China, with an exploration history of several years. Recent exploration has preliminarily indicated that the Ordovician carbonate formations in this area have some oil and gas potential. Carbonate microfacies provides material basis for reservoir development, seal formation and hydrocarbon generation. Therefore, this work utilized the standard microfacies (SMF) types to study the microfacies of the Ordovician formations in the Yubei area in order to provide theoretical basis for the next exploration. 展开更多
关键词 In New Insights into the Depositional Environments of Ordovician Carbonate Formations in the Yubei Area of Tarim Basin based on Standard Microfacies Types
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GaN-based blue laser diodes with output power of 5 W and lifetime over 20000 h aged at 60℃
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作者 Lei Hu Siyi Huang +6 位作者 Zhi Liu Tengfeng Duan Si Wu Dan Wang Hui Yang Jun Wang Jianping Liu 《Journal of Semiconductors》 2025年第4期9-11,共3页
Stimulated emission and lasing of GaN-based laser diodes(LDs)were reported at 1995[1]and 1996[2],right after the breakthrough of p-type doping[3−5],material quality[6]and the invention of high-brightness GaN-based LED... Stimulated emission and lasing of GaN-based laser diodes(LDs)were reported at 1995[1]and 1996[2],right after the breakthrough of p-type doping[3−5],material quality[6]and the invention of high-brightness GaN-based LEDs[7,8].However,it took much longer time for GaN-based LDs to achieve high power,high wall plug efficiency,and long lifetime.Until 2019,Nichia reported blue LDs with these performances[9],which open wide applications with GaN-based blue LDs. 展开更多
关键词 Blue laser diodes P type doping LIFETIME Output power Stimulated emission GAN based laser diodes stimulated emission lasing laser diodes lds
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Cost-benefit analysis of screening for diabetic retinopathy among Chinese type 2 diabetes: decision from different perspectives of a population-based study 被引量:2
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作者 Ching-Ching Peng Pesus Chou +6 位作者 Tao-Hsin Tung Wu-Hsiung Chien Fenq-Lih Lee Shih-Jen Chen Shih-Tzer Tsai Chi-Ming Liu Jorn-Hon Liu 《Health》 2009年第4期304-312,共9页
The purpose of this study is to explore whether it is worthwhile to launch a routine diabetic retinopathy (DR) screening for blindness pre-vention among Chinese type 2 diabetes from different perspective based on the ... The purpose of this study is to explore whether it is worthwhile to launch a routine diabetic retinopathy (DR) screening for blindness pre-vention among Chinese type 2 diabetes from different perspective based on the popula-tion-based study in Kinmen, Taiwan. A total of 971 community dwelling adults previously di-agnosed with type 2 diabetes in 1991-1993 un-derwent DR screening in 1999-2002 by a panel of ophthalmologists using on-site indirect oph-thalmoscopy and 45-degree color fundus retinal photographs. The cost-benefit analysis is used to evaluate the DR screening. In terms of bene-fit-cost ratio, the different screening programs for DR could save New Taiwan Dollars (NTD) from 14.38 to 36.83 in discounted costs for each dollar incurred in different screening years from the societal viewpoint for Taiwan and save NTD from 0.81 to 1.80 in different screening years from health care payer’s perspective. The av-erage estimate of willingness-to-pay to translate into benefit yields NTD from 937.8 to 4,689 be- nefits per case due to DR screening in different screening years during 10-year follow-up. The net present value of the DR screening were NTD from -167,318 to -307,251.2 in different screening years. In conclusion, it is worthwhile to initial a routine DR screening of Chinese type 2 diabetes for blindness prevention from the societal per-spective but not from consumer decision based on the willingness-to-pay perspective. 展开更多
关键词 Type 2 Diabetes DIABETIC RETINOPATHY COST-BENEFIT Analysis POPULATION-based Study
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Combined Influence of Insulin Resistance and Inflammatory Biomarkers on Type 2 Diabetes:A Population-based Prospective Cohort Study of Inner Mongolians in China 被引量:16
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作者 QIU Qiao Yan ZHANG Bei Lei +5 位作者 ZHANG Ming Zhi WU Jia Hui ZHOU Jing Wen LIANG Zhu ZHANG Yong Hong ZHANG Shao Yan 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2018年第4期300-305,共6页
This prospective study was designed to examine the combined influence of insulin resistance(IR)and inflammatory biomarker levels on type 2 diabetes mellitus(T2DM)among 1,903Inner Mongolians.
关键词 CRP DM Combined Influence of Insulin Resistance and Inflammatory Biomarkers on Type 2 Diabetes A Population-based Prospective Cohort Study of Inner Mongolians in China IR
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Optimizing the atom types of proteins through iterative knowledge-based potentials
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作者 汪心享 黄胜友 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第2期43-50,共8页
Knowledge-based scoring functions have been widely used for protein structure prediction, protein-small molecule, and protein-nucleic acid interactions, in which one critical step is to find an appropriate representat... Knowledge-based scoring functions have been widely used for protein structure prediction, protein-small molecule, and protein-nucleic acid interactions, in which one critical step is to find an appropriate representation of protein structures. A key issue is to determine the minimal protein representations, which is important not only for developing of scoring func- tions but also for understanding the physics of protein folding. Despite significant progresses in simplifying residues into alphabets, few studies have been done to address the optimal number of atom types for proteins. Here, we have investigated the atom typing issue by classifying the 167 heavy atoms of proteins through 11 schemes with 1 to 20 atom types based on their physicochemical and functional environments. For each atom typing scheme, a statistical mechanics-based iterative method was used to extract atomic distance-dependent potentials from protein structures. The atomic distance-dependent pair potentials for different schemes were illustrated by several typical atom pairs with different physicochemical proper- ties. The derived potentials were also evaluated on a high-resolution test set of 148 diverse proteins for native structure recognition. It was found that there was a crossover around the scheme of four atom types in terms of the success rate as a function of the number of atom types, which means that four atom types may be used when investigating the basic folding mechanism of proteins. However, it was revealed by a close examination of typical potentials that 14 atom types were needed to describe the protein interactions at atomic level. The present study will be beneficial for the development of protein related scoring functions and the understanding of folding mechanisms. 展开更多
关键词 atom types knowledge-based potentials statistical mechanics ITERATION
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Design of Zr-based AB_2 type hydrogen storage alloys
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作者 文明芬 王秋萍 +2 位作者 王兴海 翟玉春 陈廉 《中国有色金属学会会刊:英文版》 CSCD 2003年第6期1472-1474,共3页
The influences of the ratio of the radius of atom A(rA) to radius of atom B(rB), electronegativity and electron number were discussed on the Laves phase formation and the characteristics of Zr-based AB2 type hydro... The influences of the ratio of the radius of atom A(rA) to radius of atom B(rB), electronegativity and electron number were discussed on the Laves phase formation and the characteristics of Zr-based AB2 type hydrogen storage alloy. An enthalpy model of Zr-based AB2 alloy was obtained from known data and twelve Zr-based alloys were designed to test the model. The results show that the predicted values are in good agreement with the experimental values. The model can be used for predicting enthalpy values of Zr-based hydrogen storage alloys and settles a foundation for experiments. 展开更多
关键词 锆合金 储氢合金 AB2型 化学成分 设计
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Specific primers design based on the superoxide dismutase b gene for Trypanosoma cruzi as a screening tool:Validation method using strains from Colombia classified according to their discrete typing unit
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作者 Francisco Olmo Javier Escobedo-Ortegón +4 位作者 Patricia Palma Manuel Sánchez-Moreno Ana Mejía-Jaramillo Omar Triana Clotilde Marín 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2014年第11期854-859,共6页
Objective:To classify 21 new isolates of Trypanosoma cruai(T.cruzi) according to the Discrete Typing Unit(DTU) which they belong to,as well as tune up a new pair of primers designed to detect the parasite in biologica... Objective:To classify 21 new isolates of Trypanosoma cruai(T.cruzi) according to the Discrete Typing Unit(DTU) which they belong to,as well as tune up a new pair of primers designed to detect the parasite in biological samples.Methods:Strains were isolated,DNA extracted,and classified by using three Polymerase Chain Reactions(PCR).Subsequently this DNA was used along with other isolates of various biological samples,for a new PCR using primers designed.Finally,the amplified fragments were sequenced.Results:It was observed the predominance of DTU i in Colombia,as well as the specificity of our primers for detection of T.cruzi,while no band was obtained when other species were used.Conclusions:This work reveals the genetic variability of 21 new isolates of T.cruzi in Colombia.Our primers confirmed their specificity for detecting the presence of T.cruzi. 展开更多
关键词 TRYPANOSOMA CRUZI Polymerase chain reaction Colombia Superoxide dismutase GENE b-based primers DISCRETE typing UNIT
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Magnetic Field Induced Entropy Change for La-Fe Based NaZn_(13)-Typed Compounds
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作者 Zhang Hongwei Sun Jirong Hu Fengxia Wang Fang Shen Baogen 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第4期I0011-I0011,共1页
Magnetic field induced entropy change was investigated for La-Fe based NaZn13-type compounds with magnetic first-order phase transition. In view of magnetic refrigeration at room temperature, the developing of the mat... Magnetic field induced entropy change was investigated for La-Fe based NaZn13-type compounds with magnetic first-order phase transition. In view of magnetic refrigeration at room temperature, the developing of the materials and the understanding of the entropy change were., reviewed. For La-Fe-Si compounds, the entropy change about 29 J·kg^- 1·K^-1 was obtained at 190 K under the magnetic field of 5 T.While a large entropy change of about 15 J·kg^-1·K^-1 near room temperature under 5 T can be obtained by the substitution of Co for Fe in the compounds. It is found that the entropy change is mainly composed of that contributed from magnetic ordering and crystal lattice. The large entropy change consumed by lattice contribution is mainly due to the magnetic ordering one. 展开更多
关键词 La-Fe based NaZn13-typed compounds entropy change magnetic first-order phase transition rare earths
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Ring-opening Copolymerization of Cyclohexene Oxide and Maleic Anhydride Catalyzed by Mononuclear [Zn(L)(H_2O)] or Binuclear [Zn_2(L)(OAc)_2(H_2O)] Complex Based on the Salen-type Schiff-base Ligand 被引量:1
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作者 Li-ying Wu Dai-di Fan +1 位作者 吕兴强 卢荣 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2014年第6期768-777,共10页
From the self-assembly of the typical Salen-type Schiff-base ligand H2L and Zn(OAc)2.2H20 in the molar ratio of 1:1 or 1:2, the mononuclear [Zn(L)(H2O)] (1) or binuclear [Zn2(L)(OAc)2(H2O)] (2) are o... From the self-assembly of the typical Salen-type Schiff-base ligand H2L and Zn(OAc)2.2H20 in the molar ratio of 1:1 or 1:2, the mononuclear [Zn(L)(H2O)] (1) or binuclear [Zn2(L)(OAc)2(H2O)] (2) are obtained, respectively. For both complexes 1 and 2, the unsaturated five-coordinate coordination environment to the catalytic active centers (Zn2+ ions) permits the monomer insertion for the effective solution copolymerization of cyclohexene oxide and maleic anhydride. All the solution copolymerizations afford poly(ester-co-ether)s, while lower catalyst and co-catalyst concentrations are helpful for the formation of alternating polyester. Of the three co-catalysts, 4-(dimethylamino)pyridine is found to be the most efficient, while an excess thereof is detrimental for chain growth of the copolymers. 展开更多
关键词 Mononuclear [Zn(L)(H2O)] (1) or binuclear [Znz(L)(OAc)z(H2O)] (2) based on Salen-type Schiffobase ligandHzL Ring-opening copolymerization from CHO and MA Poly(ester-co-ether) and polyester.
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Formability of Rare Earth-Containing Solid Solution Based on Compounds with Scheelite-Type Structure
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作者 Luo Yunyun Bao Xinhua +2 位作者 Lu Wencong Chen Nianyi Xia Yiben 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第4期I0010-I0010,共1页
The regularities of the solid solutions between the scheelite-type compounds and rare earth molybdates or tungstates were investigated by the atomic parameter-support vector machine method and the intelligent database... The regularities of the solid solutions between the scheelite-type compounds and rare earth molybdates or tungstates were investigated by the atomic parameter-support vector machine method and the intelligent database of phase diagrams of molten salt systems. The crystal structure of scheelite-type compounds having M^1M^′Ⅲ (XO4)2(X = Mo, W) as common formula and the formability of the continuous solid solution between these compounds and rare earth molybdates or tungstates were also investigated. Besides, the cell constants of these compounds can be calculated by some semi-empirical equations. Based on the obtained relationships, the results of computerized prediction of the solid solubility of T1Pr (MoO4)2-Pr2 (MoO4)3 system have good agreement with experimental results. 展开更多
关键词 scheelite-type structure solid solution support vector machine (SVM) intelligent data base of phase diagrams rare earth materials design
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Identification of Question and Non-Question Segments in Arabic Monologues Using Prosodic Features: Novel Type-2 Fuzzy Logic and Sensitivity-Based Linear Learning Approaches
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作者 Sunday Olusanya Olatunji Lahouari Cheded +1 位作者 Wasfi G. Al-Khatib Omair Khan 《Journal of Intelligent Learning Systems and Applications》 2013年第3期165-175,共11页
In this paper, we extend our previous study of addressing the important problem of automatically identifying question and non-question segments in Arabic monologues using prosodic features. We propose here two novel c... In this paper, we extend our previous study of addressing the important problem of automatically identifying question and non-question segments in Arabic monologues using prosodic features. We propose here two novel classification approaches to this problem: one based on the use of the powerful type-2 fuzzy logic systems (type-2 FLS) and the other on the use of the discriminative sensitivity-based linear learning method (SBLLM). The use of prosodic features has been used in a plethora of practical applications, including speech-related applications, such as speaker and word recognition, emotion and accent identification, topic and sentence segmentation, and text-to-speech applications. In this paper, we continue to specifically focus on the Arabic language, as other languages have received a lot of attention in this regard. Moreover, we aim to improve the performance of our previously-used techniques, of which the support vector machine (SVM) method was the best performing, by applying the two above-mentioned powerful classification approaches. The recorded continuous speech is first segmented into sentences using both energy and time duration parameters. The prosodic features are then extracted from each sentence and fed into each of the two proposed classifiers so as to classify each sentence as a Question or a Non-Question sentence. Our extensive simulation work, based on a moderately-sized database, showed the two proposed classifiers outperform SVM in all of the experiments carried out, with the type-2 FLS classifier consistently exhibiting the best performance, because of its ability to handle all forms of uncertainties. 展开更多
关键词 ARABIC Monologues Prosodic Features Type-2 FUZZY LOGIC Systems Sensitivity based LINEAR LearningMethod Support Vector Machines
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Type 2 Diabetes Wellness Program in a Faith-Based Organization
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作者 Frenzy Papas Kiamco 《Journal of Diabetes Mellitus》 2016年第4期291-300,共11页
In this practicum, the program objective is to improve the health of Joseph’s Storehouse food bank recipients’ community in the Blessing Center (New Hope Free Clinic and Joseph’s food bank), Redlands, California. T... In this practicum, the program objective is to improve the health of Joseph’s Storehouse food bank recipients’ community in the Blessing Center (New Hope Free Clinic and Joseph’s food bank), Redlands, California. The approach is to implement primary prevention and secondary prevention activity to increase knowledge and skills of the clients and their families of how to prevent and control type 2 diabetes through a wellness program in the clinic. The practicum began January 2015 and ended April 2015. 53 food bank recipients (non-diabetic and diabetic) were recruited. A quasi-experimental study design, pre-test/posttest, was used for the study. The impact of the program targeted diverse audience, high risk ethnic groups, and improved knowledge, awareness, management, and positive behavioral change. The study implication for public health promotion specialists is to narrow venues targeting the most vulnerable populations to promote and reduce type 2 diabetes. 展开更多
关键词 Type 2 Diabetes California Faith-based Organization Diabetes Mellitus Public Health Wellness Program PRACTICUM Primary Prevention Secondary Prevention Diabetes in California Diabetes Disparity Diabetes Education Food Bank
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Design,synthesis and evaluation of novel cis-p-menthane type Schiff base compounds as effective herbicides 被引量:6
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作者 Shi-Chao Xu Shou-Ji Zhu +5 位作者 Jing Wang Liang-Wu Bi Yu-Xiang Chen Yan-Ju Lu Yan Gu Zhen-Dong Zhao 《Chinese Chemical Letters》 SCIE CAS CSCD 2017年第7期1509-1513,共5页
p-Menthane type monoterpene derivatives were identified as bio-based compounds with high herbicidal activities. In order to search novel p-menthane type monoterpene derivatives in good performance, a series of novel c... p-Menthane type monoterpene derivatives were identified as bio-based compounds with high herbicidal activities. In order to search novel p-menthane type monoterpene derivatives in good performance, a series of novel cis-p-menthane type Schiff base derivatives were designed and synthesized. All target products were easily available novel compounds and characterized by FT-IR,^1H NMR,^13 C NMR and ESI+-MS. Their pre-emergence herbicidal activities against annual ryegrass were evaluated. The bioassays indicated that most of the target compounds displayed excellent herbicidal activities in pre-emergence treatment. 展开更多
关键词 Turpentine derivatives Bio-based herbicides p-Menthane type compounds Schiff base derivatives Herbicidal activity
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Developing high-efficiency base editors by combining optimized synergistic core components with new types of nuclear localization signal peptide 被引量:3
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作者 Feipeng Wang Chengwei Zhang +5 位作者 Wen Xu Shuang Yuan Jinling Song Lu Li Jiuran Zhao Jinxiao Yang 《The Crop Journal》 SCIE CAS CSCD 2020年第3期408-417,共10页
The clustered regularly interspaced short palindromic repeats(CRISPR)–CRISPR-associated protein(Cas) system has been widely used for genome editing. In this system, the cytosine base editor(CBE) and adenine base edit... The clustered regularly interspaced short palindromic repeats(CRISPR)–CRISPR-associated protein(Cas) system has been widely used for genome editing. In this system, the cytosine base editor(CBE) and adenine base editor(ABE) allow generating precise and irreversible base mutations in a programmable manner and have been used in many different types of cells and organisms. However, their applications are limited by low editing efficiency at certain genomic target sites or at specific target cytosine(C) or adenine(A) residues. Using a strategy of combining optimized synergistic core components, we developed a new multiplex super-assembled ABE(sABE) in rice that showed higher base-editing efficiency than previously developed ABEs. We also designed a new type of nuclear localization signal(NLS) comprising a FLAG epitope tag with four copies of a codon-optimized NLS(F4NLS^(r2)) to generate another ABE named F4NLS-sABE. This new NLS increased editing efficiency or edited additional A at several target sites. A new multiplex super-assembled CBE(sCBE) and F4NLS^(r2) involved F4NLS-sCBE were also created using the same strategy. F4NLS-sCBE was proven to be much more efficient than sCBE in rice. These optimized base editors will serve as powerful genome-editing tools for basic research or molecular breeding in rice and will provide a reference for the development of superior editing tools for other plants or animals. 展开更多
关键词 CBE ABE NLS Developing high-efficiency base editors by combining optimized synergistic core components with new types of nuclear localization signal peptide
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Synthesis of Schiff Base Type Macrocycles Containing Naphthalene Ring 被引量:1
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作者 Chang Rong NIU Hai Ning ZHANG Cheng Tai WU(Department of Chemistry, Wuhan University, Wuhan 430072) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第7期569-572,共4页
A series of new Schiff base type macrocyclic crown ethers containing naphthalene ring were synthesized from 2,2'-di(o-formylnaphthoxy) ethyl ether or 1,2-di(o-formylnaphthoxy) ethane and four appropriate diamines.... A series of new Schiff base type macrocyclic crown ethers containing naphthalene ring were synthesized from 2,2'-di(o-formylnaphthoxy) ethyl ether or 1,2-di(o-formylnaphthoxy) ethane and four appropriate diamines. The chemical structures of the new compounds were characterized by elemental analysis, infrared spectra, nuclear magnetic resonance spectra and mass spectrometry. 展开更多
关键词 OCH IR CM KBR HNMR Synthesis of Schiff base Type Macrocycles Containing Naphthalene Ring
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Nickel/cobalt based materials for supercapacitors 被引量:5
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作者 Chenggang Wang Pengxiao Sun +2 位作者 Guangmeng Qu Jiangmei Yin Xijin Xu 《Chinese Chemical Letters》 SCIE CAS CSCD 2018年第12期1731-1740,共10页
The electrode materials as the key component of supercapacitors have attracted considerable research interests, especially for nickel/cobalt based materials by virtue of their superior electrochemical performance with... The electrode materials as the key component of supercapacitors have attracted considerable research interests, especially for nickel/cobalt based materials by virtue of their superior electrochemical performance with multiple oxidation states for richer redox reactions, abundant natural resources, lower prices and toxicity. There are many advanced electrodes based on the nickel/cobalt materials exploited for the application of supercapacitors, however, some controversial statements have induced some confusion. Herein, we refine the mechanism of energy storage for the nickel/cobalt based materials for supercapacitors and reclassify them into battery-type materials with the corresponding devices named as hybrid supercapacitors. 展开更多
关键词 Nickel/cobalt based materials Battery-type materials Pseudocapacitors EDLCs Hybrid supercapacitors
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Thermal Decomposition of Mg-PTFE Based Pyrolant in Nitrogen and Air Environments 被引量:3
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作者 Changjin Lin Hao Wang +1 位作者 Shuyuan Jiang Chenguang Zhu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2017年第3期76-80,共5页
In order to analyze the thermal decomposition of MT based pyrolant in nitrogen and air environments,the thermal analysis experiments of MT and MTV pyrolants were carried out by TG-DTA and DSC.The results show that,in ... In order to analyze the thermal decomposition of MT based pyrolant in nitrogen and air environments,the thermal analysis experiments of MT and MTV pyrolants were carried out by TG-DTA and DSC.The results show that,in nitrogen environment,the spectrum result of Grignard-type reaction~[6] is verified by the decomposition characteristics of MT and MTV pyrolants.8.71% of Mg is consumed in the intermediate reaction of MT at 500-596 ℃ and the heat release of reaction is 31.93 k J/g.The endothermic decomposition of the intermediate product is at 684-740 ℃.In MTV,the intermediate reaction is at 435-595 ℃ and the heat release of reaction are increased by the addition of fluororubber.The intermediate product degrades at 677-745 ℃.In air environment,the decomposition of MT and MTV show the different reaction mechanism from the nitrogen environment.The presence of oxygen is involved in the reaction of Mg,and inhibits the intermediate reaction process of Mg and PTFE. 展开更多
关键词 MT based pyrolant thermal decomposition Grignard-type reaction NITROGEN air
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THE EFFECT OF SUBSTITUENT ON THE THERMAL PROPERTIES OF POLYESTERS CONSISTING OF AROMATIC TYPE SCHIFF BASE MESOGENIC UNITS AND POLYMETHYLENE SPACERS
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作者 Amar H.Al-Dujaili Iman F.Mustafa Amir T.Atto 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1995年第1期51-58,共8页
Polyesters consisting of substituted aromatic type Schiff base mesogenic unit andpolymethylene spacers were synthesized and their thermal transitions and liquid crystallineproperties were studied. The liquid crystalli... Polyesters consisting of substituted aromatic type Schiff base mesogenic unit andpolymethylene spacers were synthesized and their thermal transitions and liquid crystallineproperties were studied. The liquid crystalline behaviour has been characterized by differentialscanning calorimetry (DSC) and optical polarizing microscopy. Structural broadening bysubstitution of methoxy group in 2, 2' positions of the mesogenic core produce polymers withlower transition temperatures. Polymers synthesized from ortho and meta substituted phenylenediamine did not form a liquid crystal phase. 展开更多
关键词 Liquid crystal polymer Polyesters Aromatic type schiff base Mesogenic units SPACERS
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