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China is home to 56 ethnic groups. Chin Africa presents a regular introduction to these colorful cultural groups
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《ChinAfrica》 2015年第4期64-64,共1页
THE Hanis are an ethnic farming group living in the mountainous area between the Honghe and Lancangjiang rivers in the south of Yunnan Province. Their language had no characters of its own until the Chinese Government... THE Hanis are an ethnic farming group living in the mountainous area between the Honghe and Lancangjiang rivers in the south of Yunnan Province. Their language had no characters of its own until the Chinese Government helped to create a set of characters based on Latin in the 1950s. 展开更多
关键词 China is home to 56 ethnic groups.ChinAfrica presents a regular introduction to these colorful cultural groups
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China is home to 56 ethnic groups.ChinAfrica presents a regular introduction to these colorful cultural groups.
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《ChinAfrica》 2016年第12期64-64,共1页
Uzbek〉Region:Around the 16th century,Uzbek businessmen traveled along the Silk Road to sell their goods in China.Some of them settled down in northwest China and formed the Uzbek ethnic minority of China.Today,they ... Uzbek〉Region:Around the 16th century,Uzbek businessmen traveled along the Silk Road to sell their goods in China.Some of them settled down in northwest China and formed the Uzbek ethnic minority of China.Today,they mainly live in the Xinjiang Uygur Autonomous Region.〉Population:Around 14,000〉Language:The Uzbek language belongs to the Turkic branch of the Altaic family. 展开更多
关键词 China is home to 56 ethnic groups.ChinAfrica presents a regular introduction to these colorful cultural groups
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China is home to 56 ethnic groups.Chin Africa presents a regular introduction to these colorful cultural groups
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《ChinAfrica》 2014年第12期64-64,共1页
DongTHE Dong people live mainly in Guizhou and Hunan provinces though they can also be found in the Guangxi Zhuang Autonomous Region, as well as Jiangsu, Guangdong and Zhejiang provinces. In addition to agriculture, t... DongTHE Dong people live mainly in Guizhou and Hunan provinces though they can also be found in the Guangxi Zhuang Autonomous Region, as well as Jiangsu, Guangdong and Zhejiang provinces. In addition to agriculture, they make their living by growing timber trees, which are then logged and sold. Trees are so important in their lives that they have a unique custom of planting 18 fir trees when a child is born. When the child reaches the age of 18 and gets married, the matured fir trees are felled and used to build houses for the bride and groom 展开更多
关键词 China is home to 56 ethnic groups.Chin Africa presents a regular introduction to these colorful cultural groups
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China is home to 56 ethnic groups.ChinAfrica presents a regular introduction to these colorful cultural groups.
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《ChinAfrica》 2014年第11期64-64,共1页
Bouyei )) MOST of the Bouyei people live in south Guizhou Province in southwest China, with the rest living scattered in Yunnan and Sichuan provinces and Guangxi Zhuang Autonomous Region. As valley dwellers blessed ... Bouyei )) MOST of the Bouyei people live in south Guizhou Province in southwest China, with the rest living scattered in Yunnan and Sichuan provinces and Guangxi Zhuang Autonomous Region. As valley dwellers blessed with rivers, they enjoy a fertile land and mild climate, mak- ing their living from agriculture. 展开更多
关键词 China is home to 56 ethnic groups.ChinAfrica presents a regular introduction to these colorful cultural groups
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China is home to 56 ethnic groups.ChinAfrica presents a regular introduction to these colorful cultural groups.
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《ChinAfrica》 2014年第9期64-64,共1页
Mongolian AN ethnic group known for "growing up on horsebacks," the Mongolians live mostly in the In- ner Mongolia Autonomous Region in the northern part of China, which includes vast tracts of excel- lent natural... Mongolian AN ethnic group known for "growing up on horsebacks," the Mongolians live mostly in the In- ner Mongolia Autonomous Region in the northern part of China, which includes vast tracts of excel- lent natural pastureland with numerous herds of cattle, sheep, horses and camels. The rest are also distributed in Liaoning Jilin. Heilongjiang. Qinghai and Gansu provinces. Living on grasslands and relying on raising stock as their economic mainstay, the Mongolians have kept their nomadic living style for hundreds of years. Mongolian herdsmen used to live in yurts,which were usually seven to eight feet high and 10 feet in diameter, with an opening in the top of the umbrella-shaped roof. The structure can offer ideal ventilation and good protection against wind and cold. After the mid-20th century, as more and more herdsmen ended their nomadic life and settled down, they began to build yurt-like houses made of mud and wood. 展开更多
关键词 ChinAfrica presents a regular introduction to these colorful cultural groups China is home to 56 ethnic groups
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China is home to 56 ethnic groups. ChinAfrica presents a regular introduction to these colorful cultural groups.
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《ChinAfrica》 2015年第3期64-64,共1页
Korean THE Korean people mainly reside in northeast China, Their largest concentration is in the Yanbian Ko- rean Autonomous Prefecture in Jilin Province. They can also be found in Heilongjiang and Liaoning provinces ... Korean THE Korean people mainly reside in northeast China, Their largest concentration is in the Yanbian Ko- rean Autonomous Prefecture in Jilin Province. They can also be found in Heilongjiang and Liaoning provinces and the Inner Mongolia Autonomous Region, They have their own spoken and written language, Korean. which is also the official language of South and North Korea. The ancestors of the Korean ethnic group - mostly peasants fleeing their oppressive feudal landlords - migrated from the Korean Peninsula around the late 17th century. When they settled down in China they gradually formed unique customs, Today. 展开更多
关键词 ChinAfrica presents a regular introduction to these colorful cultural groups China is home to 56 ethnic groups
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China is home to 56 ethnic groups. ChinAfrica presents a regular introduction to these colorful cultural groups.
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《ChinAfrica》 2014年第10期64-64,共1页
Tibetan THE Tibetan ethnic minority mostly lives in the Tibet Autonomous Region,but there are also Tibetan communities in Qinghai,Gansu,Sichuan and Yunnan provinces.The places they live are mostly highlands and mounta... Tibetan THE Tibetan ethnic minority mostly lives in the Tibet Autonomous Region,but there are also Tibetan communities in Qinghai,Gansu,Sichuan and Yunnan provinces.The places they live are mostly highlands and mountainous areas studded with snow-capped peaks. 展开更多
关键词 ChinAfrica presents a regular introduction to these colorful cultural groups China is home to 56 ethnic groups
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China is home to 56 ethnic groups.ChinAfrica presents a regular introduction to these colorful cultural groups.
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《ChinAfrica》 2014年第7期64-64,共1页
MAINLY distributed over Yunnan. Sichuan. Guizhou provinces and the Guangxi Zhuang Autonomous Region, the Yi is an ethnic minority with a long history and splendid culture within southwest China.
关键词 ChinAfrica presents a regular introduction to these colorful cultural groups China is home to 56 ethnic groups
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China is home to 56 ethnic groups. ChinAfrica presents a regular introduction to these colorful cultural groups.
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《ChinAfrica》 2015年第6期64-64,共1页
KazakTHE Kazak people, mainly living in the Xin- jiang Uygur Autonomous Region in northwest China, can also be found in Gansu and Qinghai provinces, where they live in small groups. The Kazak language is a fnember of... KazakTHE Kazak people, mainly living in the Xin- jiang Uygur Autonomous Region in northwest China, can also be found in Gansu and Qinghai provinces, where they live in small groups. The Kazak language is a fnember of the Turkic branch of the Altaic language family. The written language originally used the Arabic al- phabet. It is still in use but a new Latinized form was developed in 1954. 展开更多
关键词 Chin Africa presents a regular introduction to these colorful cultural groups China is home to 56 ethnic groups
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Local Characterizations of Results on the Normal Index of Subgroups in Finite Groups
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作者 Yubo LV Yangming LI Xiaoxia DONG 《Journal of Mathematical Research with Applications》 2026年第1期33-39,共7页
Let G be a finite group and H a subgroup of G.The normal index of H in G is defined as the order of K/H_(G),where K is a normal supplement of H in G such that|K|is minimal and H_(G)≤K■G.Let p be a prime which divide... Let G be a finite group and H a subgroup of G.The normal index of H in G is defined as the order of K/H_(G),where K is a normal supplement of H in G such that|K|is minimal and H_(G)≤K■G.Let p be a prime which divides the order of a group G.In this paper,some characterizations of G being p-solvable or p-supersolvable were obtained by analyzing the normal index of certain subgroups of G.These results can be viewed as local version of recent results in the literature. 展开更多
关键词 p-solvable group p-supersolvable group normal index maximal subgroup 2-maximal subgroup
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Interannual succession of phytoplankton community in a canyon-shaped drinking water reservoir during the initial impoundment period:Taxonomic versus functional groups 被引量:1
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作者 Yi Hou Ya Cheng +6 位作者 Kai Li Meng Yang Kangzhe Huang Gang Ji Ruikang Xue Tinglin Huang Gang Wen 《Journal of Environmental Sciences》 2025年第5期454-468,共15页
During the initial impoundment period of a canyon-shaped reservoir,the water body fluctuated violently regarding water level,hydrological condition,and thermal stratification.These variations may alter the structure o... During the initial impoundment period of a canyon-shaped reservoir,the water body fluctuated violently regarding water level,hydrological condition,and thermal stratification.These variations may alter the structure of phytoplankton community,resulting in algal blooms and seriously threatening the ecological security of the reservoir.It is of great significance to understand the continuous changes of phytoplankton in the initial impoundment period for the protection of reservoir water quality.Therefore,a two-year in-situ monitoring study was conducted on water quality and phytoplankton in a representative canyonshaped reservoir named Sanhekou and the interannual changes of phytoplankton community and its response to environmental changes during the initial impoundment period were discussed at taxonomic versus functional classification levels.The results showed that the total nitrogen and permanganate index levels were relatively high in the first year due to rapid water storage and heavy rainfall input,and the more stable hydrological conditions in the second year promoted the increase of algae density and the transformation of community,and the proportion of cyanobacteria increased significantly.The succession order of phytoplankton in the first year of the initial impoundment periodwas Chlorophyta-Bacillariophyta-Chlorophyta,or J/F/X1-P/MP/W1-A/X1/MP,respectively.And the succession order in the second year was Cyanobacteria/Chlorophyta-Bacillariophyta-Chlorophyta,or L_(M)/G/P-P/A/X1-X1/J/G.Water temperature,relativewater column stability,mixing depth,and pHwere crucial factors affecting phytoplankton community succession.This study revealed the interannual succession law and driving factors of phytoplankton in the initial impoundment period and provided an important reference for the operation management and ecological protection of canyon-shaped reservoirs. 展开更多
关键词 Canyon-shaped reservoir Functional groups Initial impoundment Interannual succession Water quality
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Tuning surface functional groups and crystallinity in activated carbon for high-voltage lithium-ion capacitors
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作者 AN Ya-bin SUN Yu +5 位作者 ZHANG Ke-liang LI Chen SUN Xian-zhong WANG Kai ZHANG Xiong MA Yan-wei 《新型炭材料(中英文)》 北大核心 2025年第5期1085-1097,I0019-I0021,共16页
Lithium-ion capacitors(LICs)combine the high power dens-ity of electrical double-layer capacitors with the high energy density of lithium-ion batteries.However,they face practical limitations due to the narrow operati... Lithium-ion capacitors(LICs)combine the high power dens-ity of electrical double-layer capacitors with the high energy density of lithium-ion batteries.However,they face practical limitations due to the narrow operating voltage window of their activated carbon(AC)cathodes.We report a scalable thermal treatment strategy to develop high-voltage-tolerant AC cathodes.Through controlled thermal treatment of commer-cial activated carbon(Raw-AC)under a H_(2)/Ar atmosphere at 400-800℃,the targeted reduction of degradation-prone functional groups can be achieved while preserving the critical pore structure and increasing graph-itic microcrystalline ordering.The AC treated at 400℃(HAC-400)had a significant increase in specific capacity(96.0 vs.75.1 mAh/g at 0.05 A/g)and better rate capability(61.1 vs.36.1 mAh/g at 5 A/g)in half-cell LICs,along with an 83.5%capacity retention over 7400 cycles within an extended voltage range of 2.0-4.2 V in full-cell LICs.Scalability was demonstrated by a 120 g batch production,enabling fabrication of pouch-type LICs with commercial hard carbon anodes that delivered a higher energy density of 28.3 Wh/kg at 1 C,and a peak power density of 12.1 kW/kg compared to devices using raw AC.This simple,industry-compatible approach may be used for producing ad-vanced cathode materials for practical high-performance LICs. 展开更多
关键词 Activated carbon Lithium-ion capacitors Surface functional groups Microcrystalline domains High-voltage cathod
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Synthesis and Properties of Novel A-D-A Type Molecules with Non-Fused Azacyclic End Groups
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作者 Liu Wenrui Yin Zhengchun +3 位作者 Ye Shiqi Xu Zhiwei Chen Long Wang Guanwu 《有机化学》 北大核心 2025年第4期1325-1333,共9页
Acceptor-donor-acceptor(A-D-A)type molecules,of which the novel non-fused azacyclic end-group pyrazoli-nones were modified with chlorine substitution on the phenyl ring,were synthesized.The non-fused azacyclic end-gro... Acceptor-donor-acceptor(A-D-A)type molecules,of which the novel non-fused azacyclic end-group pyrazoli-nones were modified with chlorine substitution on the phenyl ring,were synthesized.The non-fused azacyclic end-group py-razolinones have the advantages of simple synthesis steps,low cost and environmental friendliness,compared to the classical end-group dicyanomethyleneindianone.The properties of the synthesized A-D-A type molecules with non-fused azacyclic end groups were characterized by theoretical calculation,UV-vis absorption,cyclic voltammetry,X-ray diffraction and space charge limited current.It is shown that the strong UV-vis absorptions of the synthesized A-D-A type molecules are located in the wavelength range of 500~700 nm,with a moderate band gap of nearly 1.7 eV.At the same time,the influence of end-group chlorination on the properties of A-D-A type molecules was compared and explored.It is proven that this kind of A-D-A type molecule with non-fused azacyclic end groups has the potential to be applied as interfacial modified layer of the active layer in perovskite solar cell devices. 展开更多
关键词 A-D-A type molecule n-type semiconductor Non-fused end groups Medium bandgap
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PBW-bases of split affineı-quantum groups
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作者 LU Ming YANG Rui-Qi 《四川大学学报(自然科学版)》 北大核心 2025年第5期1085-1094,共10页
ı-quantum groups,arising from quantum symmetric pairs,are coideal subalgebras of quantum groups.ı-quantum groups are a vast generalization of quantum groups,as quantum groups can be viewed asıquantum groups of diagona... ı-quantum groups,arising from quantum symmetric pairs,are coideal subalgebras of quantum groups.ı-quantum groups are a vast generalization of quantum groups,as quantum groups can be viewed asıquantum groups of diagonal type.Recently,the braid group symmetries and Drinfeld new presentations of quantum groups have been generalized to affineı-quantum groups.In this paper,we construct PBW type bases for splitı-quantum groups of type ADE,based on their braid group symmetries and Drinfeld new presentations.This can be viewed as anı-analogue of the PBW-basis for affine quantum groups,and it generalizes the PBW-basis ofı-quantum groups of finite type. 展开更多
关键词 Quantum group Quantum symmetric pair PBW-base
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On σ-c-propermutable Subgroups of Finite Groups
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作者 MA Xiaojian MAO Yuemei 《数学进展》 北大核心 2025年第3期509-517,共9页
Let G be a finite group.A subgroup H of G is said to be σ-c-propermutable in G if G has a subgroup B such that G=N_(G)(H)B and for every Hall σ_(i)-subgroup B_(i) of B,there exists an element x∈B such that HB_(i)^(... Let G be a finite group.A subgroup H of G is said to be σ-c-propermutable in G if G has a subgroup B such that G=N_(G)(H)B and for every Hall σ_(i)-subgroup B_(i) of B,there exists an element x∈B such that HB_(i)^(x)=B_(i)^(x) H.In this paper,the influence of σ-c-propermutable subgroups on the structure of finite groups is investigated,and some criteria for a normal subgroup of G to be hypercyclically embedded in G are derived. 展开更多
关键词 complete Hallσ-set σ-c-propermutable subgroup supersoluble group hypercyclically embedded
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Grothendieck Groups of Finite 2-Calabi-Yau Triangulated Categories with Maximal Rigid Objects
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作者 CHANG Huimin 《数学进展》 北大核心 2025年第3期479-488,共10页
In this work,we compute the Grothendieck groups of finite 2-Calabi-Yau triangulated categories with maximal rigid objects which are not cluster tilting.These finite 2-Calabi-Yau triangulated categories are divided int... In this work,we compute the Grothendieck groups of finite 2-Calabi-Yau triangulated categories with maximal rigid objects which are not cluster tilting.These finite 2-Calabi-Yau triangulated categories are divided into,by the work of Amiot[Bull.Soc.Math.France,2007,135(3):435-474](see also[Adv.Math.,2008,217(6):2443-2484]and[J.Algebra,2016,446:426-449]),three classes:type A,type D and type E. 展开更多
关键词 finite 2-Calabi-Yau triangulated category Grothendieck group Dynkin quiver
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Carbon nitride quantum dots decorated with cyano groups for boosting photocatalytic hydrogen peroxide production
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作者 Ke Kong Hong Zhong +3 位作者 Dejian Chen Fushuai Zhang Xiaoju Li Ruihu Wang 《Green Energy & Environment》 2025年第7期1551-1558,共8页
The photocatalytic hydrogen peroxide(H_(2)O_(2))production by graphitic carbon nitride is a sustainable and environment-benign alternative approach of conventional anthraquinone autoxidation technology,but it is great... The photocatalytic hydrogen peroxide(H_(2)O_(2))production by graphitic carbon nitride is a sustainable and environment-benign alternative approach of conventional anthraquinone autoxidation technology,but it is great challenges to promote two-electron O_(2)reduction and water oxidation.Herein,we present the well-dispersed graphitic carbon nitride quantum dots decorated with cyano groups(Na-CNQD and K-CNQD)by thermal polymerization of melamine in the presence of metal fluoride.The quantum confinement and edge effect have endowed the photocatalysts with rich active sites,wide light absorption range and the inhibited charge recombination.The cyano moieties function as O_(2)reduction centers to accept the photogenerated electrons and facilitate their rapid transfer to O_(2)molecules.This process enables the selective two-electron reduction of O_(2),leading to the production of H_(2)O_(2).Concurrently,the valence band holes on the heptazine moiety oxidize water into H_(2)O_(2).These synergistic effects promote photocatalytic H_(2)O_(2)production from O_(2)and H_(2)O without the need for additional photosensitizers,organic scavengers and co-catalysts.In contrast,pristine carbon nitride nanosheets remain inactive under the same conditions.This study offers new strategies for rational design of carbon-based materials for solar-to-chemical energy conversion. 展开更多
关键词 PHOTOCATALYSIS Carbon nitride Hydrogen peroxide Quantum dots Cyano groups
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Grounded in the Municipal Industry-Education Consortium: Organizational Logic and Construction Pathways for Art and Design Specialty Groups
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作者 Dong Ye Junzhu Nie 《Journal of Contemporary Educational Research》 2025年第11期115-125,共11页
With the transformation and upgrading of industries,along with the rapid advancement of artificial intelligence(AI)technologies,higher vocational education in art and design is facing new developmental challenges.As a... With the transformation and upgrading of industries,along with the rapid advancement of artificial intelligence(AI)technologies,higher vocational education in art and design is facing new developmental challenges.As an emerging integrative ecosystem,the municipal industry-education consortium offers a strategic pathway to address these challenges by deepening collaboration between education and industry and fostering the coordinated development of both sectors.Grounded in the framework of the municipal industry-education consortium,this study proposes a top-level organizational model for art and design specialty groups characterized by industry-chain-driven development,interdisciplinary integration,and growth-employment orientation.It further explores multiple development pathways,including innovations in consortium council governance,dynamic talent cultivation models,shared curriculum systems,dual-track teaching teams,and multi-tiered practice bases.Collectively,these pathways establish a comprehensive specialty group system in which core specialties drive development,supporting specialties ensure interdependence,and extended specialties foster mutual advancement.The findings provide theoretical insights and practical guidance for advancing the modernization and high-quality transformation of vocational art and design education,contributing to the cultivation of innovative and application-oriented professionals aligned with industrial restructuring and the development of new productive forces. 展开更多
关键词 Municipal industry-education consortium Art and design specialty groups Organizational logic of specialty groups Construction pathway
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Charged functional groups modified porous spherical hollow carbon material as CDI electrode for salty water desalination
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作者 Yushan Ni Yunlong Pu +3 位作者 Jie Zhang Weiyan Cui Mingjun Gao Dongjiang You 《Journal of Environmental Sciences》 2025年第3期254-267,共14页
As a new electrochemical technology,capacitive deionization(CDI)has been increasingly applied in environmental water treatment and seawater desalination.In this study,functional groups modified porous hollow carbon(HC... As a new electrochemical technology,capacitive deionization(CDI)has been increasingly applied in environmental water treatment and seawater desalination.In this study,functional groups modified porous hollow carbon(HC)were synthesized as CDI electrode material for removing Na^(+)and Cl^(−)in salty water.Results showed that the average diameter of HC was approximately 180 nm,and the infrared spectrum showed that its surface was successfully modified with sulfonic and amino groups,respectively.The sulfonic acid functionalized HC(HC-S)showed better electrochemical and desalting performance than the amino-functionalized HC(HC–N),with a maximum Faradic capacity of 287.4 F/g and an adsorptive capacity of 112.97 mg/g for NaCl.Additionally,92.63%capacity retention after 100 adsorption/desorption cycles demonstrates the excellent stability of HC-S.The main findings prove that HC-S is viable as an electrodematerial for desalination by high-performance CDI applications. 展开更多
关键词 Hollow carbon Functional groups DESALINATION Capacitive deionization
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Groups 3 and 4 single-site catalysts for olefin-polar monomer copolymerization
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作者 Chengkai Li Guoqiang Fan +2 位作者 Gang Zheng Rong Gao Li Liu 《Chinese Chemical Letters》 2025年第9期34-45,共12页
Introducing functional polar groups into polyolefins can significantly improve the material properties,but there are still challenges in achieving this goal,with the core difficulty being that polar groups are prone t... Introducing functional polar groups into polyolefins can significantly improve the material properties,but there are still challenges in achieving this goal,with the core difficulty being that polar groups are prone to interact with metal active species,affecting the efficiency of the copolymerization.With the rapid advancement in catalyst,a variety of copolymerization strategies are developed aimed at producing more versatile polyolefin materials.Although early transition metal catalysts play an indispensable role in the traditional polyolefin industry,their inherent strong oxophilicity becomes a significant constraint in copolymerization involving polar olefins,limiting their application scope.This review summarizes the progress made in recent years in the efficient copolymerization of non-polar olefins with polar comonomers catalyzed by groups 3 and 4 single-site catalysts.We classify the catalysts into four categories,Sc-,Ti-,Zr-,Hf-,based on the type of metal centers,and provide insights into the influence of catalyst structures and the type of comonomers on the copolymerization behavior.The introduction of polar monomers fundamentally improves the comprehensive performance of the products,greatly broadens the application scope of polyolefin materials,and meets the growing market demand for multifunctional and high-performance materials. 展开更多
关键词 Single-site catalysts groups 3 and 4 metal Polar monomers COPOLYMERIZATION Physical properties
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