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Malawi Opens Tourism Doors No visa’s needed for Chinese tourists and others,as Malawi makes visits more convenient
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作者 EDWIN NYIRONGO 《ChinAfrica》 2024年第5期42-43,共2页
When Malawian President Lazarus Chakwera delivered a State of the Nation Address at the 50th Parliamentary Session and Budget Meeting in February,tourism was top of mind.
关键词 law convenient Open
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Efficient and Convenient Procedures forthe Formation and cleavage of steroid acetals catalysed by montmorillonite aite K 10 被引量:87
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《Chinese Chemical Letters》 SCIE CAS CSCD 1996年第11期975-978,共4页
Acetalization of steroid ketones and cleavage of the acetals have ben carried out inexcellent yield under catalysis of montmorillonite K 10.
关键词 MONTMORILLONITE catalysed STEROID CLEAVAGE convenient
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A New Convenient Synthesis of Pyridine-N-oxides 被引量:3
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作者 Tao LU Xin Zhong SHI Yi Ming WU(Dept.of Organic Chemistry, China Pharmaceutical University,Nanjing, Jiangsu 210009) 《Chinese Chemical Letters》 SCIE CAS CSCD 1996年第10期907-908,共2页
This paper describes the direct oxidation of pyridines to pyridine-N-oxides by means of 30% H2O2 in aq media in the presence of Na2WO4.2H(2)O as catalyst instead of with per-acids or 30% H2O2 in acetic acid. Good yiel... This paper describes the direct oxidation of pyridines to pyridine-N-oxides by means of 30% H2O2 in aq media in the presence of Na2WO4.2H(2)O as catalyst instead of with per-acids or 30% H2O2 in acetic acid. Good yields were obtained. 展开更多
关键词 A New convenient Synthesis of Pyridine-N-oxides
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Evaluation of Control Effects against Sugarcane Pests:A New Sustained-release and Long-lasting Pesticide and Convenient and Efficient Pesticide Application Technology 被引量:1
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作者 Li Wenfeng Pu Chunhua +5 位作者 Zhang Rongyue Yin Jiong Luo Zhiming Shan Hongli Wang Xiaoyan Huang Yingkun 《Plant Diseases and Pests》 CAS 2017年第5期11-14,共4页
[Objective]The paper was to screen a new ideal sustained-release,long-lasting and low-toxic pesticide and convenient and efficient pesticide application technology for controlling Ceratovacuna lanigera and Baliathrips... [Objective]The paper was to screen a new ideal sustained-release,long-lasting and low-toxic pesticide and convenient and efficient pesticide application technology for controlling Ceratovacuna lanigera and Baliathrips serratus. [Method]2% Imidacloprid GR were selected and applied in the soil for field efficacy trial. [Result] The optimum dosage of 2% imidacloprid GR was 30 kg/hm^2( active ingredient 600 g),which can be mixed with fertilizer( 30 kg pesticide and 40-80 kg fertilizer per hm^2) once combined with sugarcane planting management or big ridging during February and June. The control effects against C. lanigera and B. serratus could be more than 98. 2% and 81. 1%,respectively. The actual yield and sugar content in various pesticide treatments were increased by 33 390 kg/hm^2 and 6. 6% respectively compared to blank control. [Conclusion]2% imidacloprid GR has good control effects on C. lanigera and B. serratus. It is a new pesticide with ideal sustained-release,long-lasting and low-toxin effects against C. lanigera and B. serratus. Therefore,it could be used alternatively with other pesticides,to delay production and development of drug resistance. 展开更多
关键词 Sustained-release and long-lasting pesticide convenient and efficient pesticide application Sugarcane pests Control effect evaluation
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A Convenient Method for the Synthesis of 1,3,2-Oxazaphospholidin-[3,2-a]-8-oxo-10-thio(or seleno)-[1,3,2]-benzodiazaphosphorines
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作者 Deng, SL Huang, JM Chen, RY 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第10期867-870,共4页
A Convenient method for the synthesis of fused phosphorusheterocycle 1,3,2-oxazaphosphorin-[3.2-a]-8-oxo-10-thio(or seleno)-[1,3,2]-benzodiazaphosphorines was carried out in one pot by the reaction of Tris(diethylamin... A Convenient method for the synthesis of fused phosphorusheterocycle 1,3,2-oxazaphosphorin-[3.2-a]-8-oxo-10-thio(or seleno)-[1,3,2]-benzodiazaphosphorines was carried out in one pot by the reaction of Tris(diethylamino)phosphine with multifunctional compounds 2-(N-(beta or gamma-hydroxyl) alkylene) amino-benzamides 1. When PCL3 was used, only chlorinated product was obtained. 展开更多
关键词 convenient method synthesis multifunctional compounds fused phosphorus heterocycle one-pot
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A CONVENIENT ASYMMETRIC SYNTHESIS OF 1-AMINOALKYLPHOSPHONIC ACIDS^+
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作者 Cheng Ye YUAN Shu Sen LI Guo Quan WANG Hao WU Shanghai Institute of Organic Chemistry,Academia Sinica,345 Lingling Lu,Shanghai 200032 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第9期753-756,共4页
A convenient method for the asymmetric synthesis of 1-amino- alkylphosphonic acids was described.It involved the diastereoselctive alkylation of bicyclic chloromethylphosphonamide derived from(S)-2-ani- linomethylpyrr... A convenient method for the asymmetric synthesis of 1-amino- alkylphosphonic acids was described.It involved the diastereoselctive alkylation of bicyclic chloromethylphosphonamide derived from(S)-2-ani- linomethylpyrrolidine followed by subsequent conversions leading to amino compounds by Staudinger method.Acid hydrolysis afforded the target molecule in good yield. 展开更多
关键词 CDC cm PPM A convenient ASYMMETRIC SYNTHESIS OF 1-AMINOALKYLPHOSPHONIC ACIDS MHz HRMS
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A NEW CONVENIENT METHOD FOR THE SYNTHESIS OF PERFLUOROALKYL 2H-PYRROLE
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作者 Wei Yuan HUANG Wu Ping MA Shanghai Institute of Organic Chemistry, The Chinese Academy of Sciences, 345 Lingling Lu, Shanghai, 200032. 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第10期755-756,共2页
The reaction between 2,5-Dimethylpyrrole (1) and R_FI (2)(R_F: a, Cl(CF_2)_4; b, Cl(CF_2)_6; c, Cl(CF_2)_8; d, n-C_6F_(13); e, n-C_8F_(17)) in the presence of Na_2S_2O_4-NaHCO_3 in acetonitrile resulted in the formati... The reaction between 2,5-Dimethylpyrrole (1) and R_FI (2)(R_F: a, Cl(CF_2)_4; b, Cl(CF_2)_6; c, Cl(CF_2)_8; d, n-C_6F_(13); e, n-C_8F_(17)) in the presence of Na_2S_2O_4-NaHCO_3 in acetonitrile resulted in the formation of 2-perfluoroalkyl-2,5-dimethyl-2H-pyrrole (3) as a major product in good yield. 展开更多
关键词 Cl A NEW convenient METHOD FOR THE SYNTHESIS OF PERFLUOROALKYL 2H-PYRROLE CF CHEN WANG
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A SIMPLE AND CONVENIENT ROUTE FOR PREPARATION OF OPTICALLY ACTIVE BICYCLOLACTONES
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作者 Hui Jun WU Qi WEI Hai Jian SHI Liang CHEN Shou Yuan LIN Department of Chemistry,East China Normal University,Shanghai 200062 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第6期493-494,共2页
Optically active bicyclolactones 4 were prepared via a new simple route.
关键词 IR CM CCI A SIMPLE AND convenient ROUTE FOR PREPARATION OF OPTICALLY ACTIVE BICYCLOLACTONES
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STUDIES ON THE REACTION OF SULFUR,SELENIUM AND TELLURIUM WITH SODIUM HYDROXIDE UNDER PHASE TRANSFER CATALYSIS(Ⅱ).A CONVENIENT METHOD FOR THE SYNTHESIS OF BI(ACYL)DISULFIDES
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作者 Jin-Xian WANG(Chin-Hsien WANG) Wenfeng CUI Yulai HU Kai ZHAO Institute of Chemistry,Department of Chemistry,Northwest Normal University,Lanzhou,730070 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第3期193-196,共4页
A simple and general method for the synthesis of bi(acyl)disulfides is reported.Sulfur is allowed to react with sodium hydroxide to give sodium disulfide at 65℃ under PTC,which can react with acyl halides to afford b... A simple and general method for the synthesis of bi(acyl)disulfides is reported.Sulfur is allowed to react with sodium hydroxide to give sodium disulfide at 65℃ under PTC,which can react with acyl halides to afford bi(acyl)disulfides in good to excellent isolated yields.The effects of solvents and phase transfer catalysts are discussed. 展开更多
关键词 In Wang ACYL)DISULFIDES STUDIES ON THE REACTION OF SULFUR SELENIUM AND TELLURIUM WITH SODIUM HYDROXIDE UNDER PHASE TRANSFER CATALYSIS A convenient METHOD FOR THE SYNTHESIS OF BI PEG OC Ph
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A CONVENIENT SYNTHESIS OF AROMANTIC ACID-2-HYDRAZONE-1,3-DITHIOLAN-4-ONE AS POSSIBLE ANTIFUNGAL AGENTS
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《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第S1期434-434,共1页
关键词 ACID AS A convenient SYNTHESIS OF AROMANTIC ACID-2-HYDRAZONE-1 3-DITHIOLAN-4-ONE AS POSSIBLE ANTIFUNGAL AGENTS
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Malaysia Promotes Various Convenient Measures to Attract More Chinese Tourists——Interview with Zalizam Zakaria, Tourism Minister of Malaysia Embassy
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作者 Guo Yan 《China's Foreign Trade》 2019年第3期17-19,共3页
Malaysia has many worldclass tourist spots,like Kuala Lumpur,Malacca,Pulau Langkawi and Sabah.Malaysia’s musang king is the top delicious’food for world gourmets.According to the recent data released by Malaysia’s ... Malaysia has many worldclass tourist spots,like Kuala Lumpur,Malacca,Pulau Langkawi and Sabah.Malaysia’s musang king is the top delicious’food for world gourmets.According to the recent data released by Malaysia’s Ministry of Tourism,China ranked the third in terms of number of tourists visiting Malaysia in 2018,with about 2.94 million tourists in all.This year marks the 45th anniversary of the establishment of diplomatic relations between China and Malaysia. 展开更多
关键词 INTERVIEW with Zalizam Zakaria MALAYSIA Promotes Various convenient Measures to Attract More Chinese Tourists TOURISM MINISTER of MALAYSIA EMBASSY
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A CONVENIENT SYNTHESIS OF CYCLOOCTANE DERIVATIVES
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作者 Yu Jin HUANG Xi YanLU Shanghai Institute of Organic Chemistry,Academia Sinica,345 Lingling Lu,Shanghai 200032,China 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第1期31-32,共2页
1,5-Bismethylene cyclooctane derivatives were synthesized by the palladium catalyzed annulation reaction of 2-methylene propane-1,3-diol diacetate with compounds containing active methylene groups in the presence of BSA.
关键词 HRMS A convenient SYNTHESIS OF CYCLOOCTANE DERIVATIVES
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A NEW CONVENIENT SYNTHESIS OF S-ALKYL N,N-DIALKYL THIOPHOSPHORAMIDIC ACID DERIVATIVES
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作者 Chu Chi TANG Gui Ping WU Institute of Elemento-Organic Chemistry,Nankai University,Tianjin 300071 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第8期593-594,共2页
The chlorination of O,O-dialkyl N,N-dialkyl thiophosphoramidates with phosphorus oxychloride proceeds with isomerization to give S-alkyl N,N-dialkyl thiophosphoramidochloridates,which react further with various nucleo... The chlorination of O,O-dialkyl N,N-dialkyl thiophosphoramidates with phosphorus oxychloride proceeds with isomerization to give S-alkyl N,N-dialkyl thiophosphoramidochloridates,which react further with various nucleophiles in the presence of base to give the title compounds. 展开更多
关键词 ACID A NEW convenient SYNTHESIS OF S-ALKYL N N-DIALKYL THIOPHOSPHORAMIDIC ACID DERIVATIVES
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A Convenient Method for Dehydrogenation of Symmetric Hydrazo Compounds
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《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第S1期318-318,共1页
关键词 A convenient Method for Dehydrogenation of Symmetric Hydrazo Compounds
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A CONVENIENT SYNTHESIS OF FLUORINE-CONTAINING QUINOLINES
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作者 Wei Yuan HUANG Yan Song LIU Long Lü,Shanghai Institute of Organic Chemistry,The Chinese Academy of Sciences,345 Lingling Lu,Shanghai,200032 《Chinese Chemical Letters》 SCIE CAS CSCD 1992年第8期583-584,共2页
2-Fluoroalkyl-4-hydroxy-quinolines were easily obtained from the reactions of 2-(F-alkyl)acetates with aromatic amines in the presence of Et_3N,followed by cyclization of the intermediates with PPA.
关键词 A convenient SYNTHESIS OF FLUORINE-CONTAINING QUINOLINES
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A CONVENIENT SYNTHESIS OF PERFLUOROALRYLBENZO CROWN ETHERS
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作者 Wei Yuan HUANG Jin Tao LIU 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第5期347-348,共2页
Perfluoroalkylbenzo crown ethers were readily prepared from the reaction of benzo crown ethers with sodium perfluoroalkanesulfinates in the presence of an oxidizing agent such as Ce(SO_4)_2 or Mn(OAC)_3.2H_2O in good ... Perfluoroalkylbenzo crown ethers were readily prepared from the reaction of benzo crown ethers with sodium perfluoroalkanesulfinates in the presence of an oxidizing agent such as Ce(SO_4)_2 or Mn(OAC)_3.2H_2O in good yields through a radical process. 展开更多
关键词 A convenient SYNTHESIS OF PERFLUOROALRYLBENZO CROWN ETHERS
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Three-dimensional Construction of Convenient Travel System for the Elderly
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作者 赵树坤 HU Liang(译) 《The Journal of Human Rights》 2022年第4期737-758,共22页
Population aging brings a severe challenge to all social systems.In recent years,laws and policies at the central and local levels have provided many norms and guidelines to ensure accessible travel for elderly people... Population aging brings a severe challenge to all social systems.In recent years,laws and policies at the central and local levels have provided many norms and guidelines to ensure accessible travel for elderly people.However,there are still some challenges in practice,such as vague standards for a barrier-free environment,uneven satisfaction with barrier-free public transport,the unbalanced supply of public services,and the gap in information intelligence.The three dimensions of concept,system,and multiple social subjects should be highlighted in order to strengthen the protection of convenient travel for the elderly.We should consolidate“inclusiveness,”“positivity,”and“mainstreaming”as the internal nutrients of the system,keep polishing the system and improving the system effect,and give full play to market forces and stimulate the functions of industrial and commercial enterprises. 展开更多
关键词 the elderly convenient travel CONCEPT SYSTEM MARKET
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ITMA ASIA + CITME 2010 Exhibition Space Sold Out Visitors offered convenient online registration and badge printing service
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《China Textile》 2010年第5期22-22,共1页
The reputation of ITMA ASIA+ClTME 2010 as Asia’s premier textile industry platform has been given a further boost following an announcement from the show organizers that all exhibition space has now been sold. Over 1... The reputation of ITMA ASIA+ClTME 2010 as Asia’s premier textile industry platform has been given a further boost following an announcement from the show organizers that all exhibition space has now been sold. Over 1,100 textile and garment machinery manufacturers have applied successfully to exhibit at the second combined show,taking up 100,000 square meters of Shanghai New International Expo Centre. 展开更多
关键词 ITMA ASIA ASIA CITME 2010 Exhibition Space Sold Out Visitors offered convenient online registration and badge printing service 2010
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Knowledge and the Attitude on the Use of Mouthwash among Two Selected Senior High Schools in Kumasi
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作者 Ama Agyeibea Amuasi Kwame A. Koranteng Joseph Abu-Sakyi 《Open Journal of Stomatology》 2024年第5期218-234,共17页
BACKGROUND: The route of most systemic diseases begins in the oral cavity. Oral health knowledge of mouthwashes and their uses is indispensable for the general population and especially adolescents. The use of mouthwa... BACKGROUND: The route of most systemic diseases begins in the oral cavity. Oral health knowledge of mouthwashes and their uses is indispensable for the general population and especially adolescents. The use of mouthwash by adolescents can be a beneficial adjunct to their oral hygiene routine, providing additional protection against dental diseases and promoting fresher breath. Overuse or misuse of mouthwash, particularly those containing alcohol or other potentially irritating ingredients, may lead to adverse effects such as oral mucosal irritation, dry mouth, or alteration of the oral microbiome. OBJECTIVES: To determine the knowledge, attitude, and use of mouthwash among senior high school students in Kumasi. METHODOLOGY: 120 students responded to a standard questionnaire by a convenient sample technique. The Statistical Package for Social Sciences (SPSS) 22.0 and MS Excel were used for data management and analysis. The results of the study were presented using tables, bar charts, and pie chart. RESULTS: The ages of the respondents ranged from 14 to 20 years. Out of the 120 participants, 71 students that represent 59.2% of the total, used mouthwash. Majority of the participants (63%) utilized a mouthwash after brushing their teeth. 49% of the participants reported using mouthwash to address halitosis, 37% used it to combat periodontal disease, and 10% used it for relief from a sore throat. CONCLUSION: In general, most of the participants who use mouthwash had excellent knowledge and a positive attitude toward the use of mouthwash. 展开更多
关键词 Oral Cavity MOUTHWASH Plaque Biofilm GINGIVITIS convenient Sampling
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China’s Low-Altitude Economy is Ready for Takeoff
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作者 Zhang Shasha 《China Report ASEAN》 2024年第2期30-31,共2页
On Shenzhen,Guangdong Province,a city known for its tech innovation,residents have recently adopted helicopters as“air taxis”alongside buses,cabs and the subway.On board these air taxis,passengers are treated to pan... On Shenzhen,Guangdong Province,a city known for its tech innovation,residents have recently adopted helicopters as“air taxis”alongside buses,cabs and the subway.On board these air taxis,passengers are treated to panoramic views of the city’s picturesque landscapes,making their journeys both convenient and alluring. 展开更多
关键词 RESIDENTS landscape convenient
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