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不老“中国流”
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作者 邵炜刚 《围棋天地》 2002年第5期71-72,共2页
中国流布局历经四十年风雨.依然魅力不减.层出不穷的新手新型是其长盛不衰秘诀。本文向您介绍的就是最新的一种变化。
关键词 “中国流” 新手 秘诀 布局 魅力 变化 风雨
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激扬“中国流”:初越“天王山”
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作者 王磊 《围棋天地》 2002年第10期8-14,共7页
“忽如一夜春风来,干树万树梨花开”。春风远度,自韩国大田劲吹而至。第7届三星杯,六位国手进入了八强。环顾身周,只剩下日薄西山的曹薰铉和难成大器的崔明勋。中国围棋一只手巳抚在了三星杯耳之上。
关键词 三星杯 “中国流” 崔明勋 曹薰铉 围棋 韩国 天王 梨花
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“韩流”走了“中国流”来了!
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《消费》 2009年第9期32-34,共3页
似乎在一夜之间,那些韩流的拥趸们发现了,国产剧占据了荧幕的大半壁江山。《纸醉金迷》在热播,《潜伏》在热播,《走西口》在热播,《北风那个吹》在热播。 于是,时尚嗅觉本就灵敏、情商和智商都不断调整的白领们发现了,一股国产... 似乎在一夜之间,那些韩流的拥趸们发现了,国产剧占据了荧幕的大半壁江山。《纸醉金迷》在热播,《潜伏》在热播,《走西口》在热播,《北风那个吹》在热播。 于是,时尚嗅觉本就灵敏、情商和智商都不断调整的白领们发现了,一股国产影视剧的旋风正在刮起,和当年风靡一时的“韩流”相对的“中国流”开始潜入了我们的生活。 展开更多
关键词 “中国流” “韩流” 《走西口》 国产剧 热播 影视剧
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计算与感觉(65):又见“中国流”
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《围棋天地》 2011年第15期81-82,共2页
最近一段时间,中国流布局在世界棋坛又掀起了热潮。有棋手曾说,中国流布局善守又善攻,因此,职业高手中也不乏它的忠实拥趸。本期精选了十局最近高手下出的实战谱,您会和他们的选点相同吗?
关键词 “中国流” 感觉 棋手
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世界优秀羽毛球女单选手戴资颖发接发阶段技战术特征分析 被引量:4
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作者 王怡 戴劲 《青少年体育》 2019年第2期77-78,共2页
回顾羽毛球女单打法,以控制底线为主的“拉吊突击”打法在2012 年以前最少20 年里都占据着主导地位,也可以称之为世界女单的“中国流”时代。现在,以戴资颖为代表的女单打法,可以说完全颠覆了传统打法观念,逢高必压的意识和能力,已经迫... 回顾羽毛球女单打法,以控制底线为主的“拉吊突击”打法在2012 年以前最少20 年里都占据着主导地位,也可以称之为世界女单的“中国流”时代。现在,以戴资颖为代表的女单打法,可以说完全颠覆了传统打法观念,逢高必压的意识和能力,已经迫使当今女单的制胜能力超越传统相对单一的控制底线能力,向着更难、更深的层面推进,如网前技术的限制能力和底线进攻的连贯能力等。 展开更多
关键词 羽毛球 技战术特征 女单 世界 选手 “中国流” 能力 打法
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Analysis of anthropogenic aluminum cycle in China 被引量:4
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作者 岳强 王鹤鸣 +1 位作者 陆钟武 智升科 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第4期1134-1144,共11页
Anthropogenic aluminum cycle in China was analyzed by the aluminum flow diagram based on the life cycle of aluminum products. The whole anthropogenic aluminum cycle consists of four stages: alumina and aluminum produ... Anthropogenic aluminum cycle in China was analyzed by the aluminum flow diagram based on the life cycle of aluminum products. The whole anthropogenic aluminum cycle consists of four stages: alumina and aluminum production, fabrication and manufacture, use and reclamation. Based on the investigation on the 2003-2007 aluminum cycles in China, a number of changes can be found. For instance, resources self-support ratio (RSR) in alumina production dropped from 95.42%to 55.50%, while RSR in the aluminum production increased from 52.45%to 79.25%. However, RSR in the Chinese aluminum industry leveled off at 50%in the period of 2003-2007. The respective use ratios of domestic and imported aluminum scrap in the aluminum industry of 2007 were 5.38% and 9.40%. In contrast, both the net imported Al-containing resources and the lost quantity of Al-containing materials in aluminum cycle increased during the same period, as well as the net increased quantity of Al-containing materials in social stock and recycled Al-scrap. Proposals for promoting aluminum cycle were put forward. The import/export policy and reducing the loss of Al-containing materials for the aluminum industry in China in the future were discussed. 展开更多
关键词 ANTHROPOGENIC aluminum cycle in China SFA weighted average method average use life
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中国流:术语
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《围棋天地》 2011年第21期111-111,共1页
当代一大布局门类,几十年盛行不衰。中国流原型如图一所示,为上世纪六十年代日本安永一创案,第5手不按当时常规缔角而占边兼顾上下是其别出心裁之处。以陈祖德为代表的中国棋手加以研究,1963年开始试用,并于1965年中国棋手访日比... 当代一大布局门类,几十年盛行不衰。中国流原型如图一所示,为上世纪六十年代日本安永一创案,第5手不按当时常规缔角而占边兼顾上下是其别出心裁之处。以陈祖德为代表的中国棋手加以研究,1963年开始试用,并于1965年中国棋手访日比赛中全面使用。1965年,日本棋手岛村俊广九段访华后接触到这种布局,返日后大量使用,胜率颇高,日本棋界遂将此布局命名为“中国流”。 展开更多
关键词 “中国流” 中国棋手 术语 六十年代 日本 陈祖德 赛中 胜率
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中国围棋驱散"韩流"
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作者 谢锐 《新体育》 2013年第11期63-65,共3页
进入2013年后的世界围棋大赛进程大抵是这样的:16强中,中国棋手占据10个以上的席位,韩国2至5个,日本1至2个;八强中,中国棋手差不多要占据六席,最终包揽决赛甚至四强。昔日强大的“韩流”而今在“中国流”的倒逼之下,由攻势转为... 进入2013年后的世界围棋大赛进程大抵是这样的:16强中,中国棋手占据10个以上的席位,韩国2至5个,日本1至2个;八强中,中国棋手差不多要占据六席,最终包揽决赛甚至四强。昔日强大的“韩流”而今在“中国流”的倒逼之下,由攻势转为守势。乃至放弃抵抗。 展开更多
关键词 中国围棋 “韩流” 中国棋手 “中国流” 攻势
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林泰辅与唐兰:中日古文字学现代理论初次建构——以新发现《中国文字源流》稿本(1907)为核心
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作者 李无未 魏小燕 《古汉语研究》 CSSCI 北大核心 2023年第2期112-125,128,共15页
日本林泰辅东京大学博士学位论文《中国文字源流》稿本(1907)的发现,带来了人们对中日古文字学现代理论体系形成过程的新认识。中国唐兰的《古文字学导论》(1934)是中国古文字现代理论体系的标志性成果之一。比较二者之间创新性观点,比... 日本林泰辅东京大学博士学位论文《中国文字源流》稿本(1907)的发现,带来了人们对中日古文字学现代理论体系形成过程的新认识。中国唐兰的《古文字学导论》(1934)是中国古文字现代理论体系的标志性成果之一。比较二者之间创新性观点,比如林泰辅将中国文字分为篆体时代与隶楷时代、提出象形、指事两大造字“纲领”说、古文字变迁三期说、“字形比较法”、从地域差异角度研究古文字等,与唐兰一起代表了20世纪初的中日两国中国古文字学理论研究的最新成果,意义非凡。 展开更多
关键词 林泰辅 唐兰 中国文字源 《古文字学导论》
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The HIV epidemic in China: history, response, and challenge 被引量:17
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作者 Na HE Roger DETELS 《Cell Research》 SCIE CAS CSCD 2005年第11期825-832,共8页
The first case of AIDS was reported in 1985 in China, but by the early 21st century, the government estimated that there were 840,000 citizens living with HIV/AIDS. The number is increasing rapidly. The major risk gro... The first case of AIDS was reported in 1985 in China, but by the early 21st century, the government estimated that there were 840,000 citizens living with HIV/AIDS. The number is increasing rapidly. The major risk groups are injection drug users (IDUSs; 43%) and former plasma donors (27%), but rates among heterosexual groups are rising rapidly. Sentinel surveillance was initiated in 1986, and now includes IDUs, men-who-have-sex-with-men, sexually transmitted disease clinic attendees, antenatal women, long-distance truck drivers, and sex workers. Although the government was slow to respond to the epidemic in the late 20th century, it has made a vigorous response in the early 21st century. Components of that response include implementation and evaluation of harm reduction programs for IDUs, education to increase knowledge and reduce stigma, treatment and social support for rural and poor HIV/AIDS patients, widespread testing, and increased funding for HIV/AIDS programs. International agencies have been generous in their support of the government initiatives. To successfully combat the epidemic, China needs to develop and train the necessary infra- structure to implement its intervention programs, particularly in the rural areas, to vigorously combat stigma and discrimination, support research especially in the universities and research institutions other than the China Centers for Disease Control, develop a system for efficient exchange of research and program information, and update legislation to reflect the current situation. 展开更多
关键词 HIV/AIDS China EPIDEMIC
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Landslide susceptibility mapping using an integrated model of information value method and logistic regression in the Bailongjiang watershed,Gansu Province,China 被引量:20
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作者 DU Guo-liang ZHANG Yong-shuang +2 位作者 IQBAL Javed YANG Zhi-hua YAO Xin 《Journal of Mountain Science》 SCIE CSCD 2017年第2期249-268,共20页
Bailongjiang watershed in southern Gansu province, China, is one of the most landslide-prone regions in China, characterized by very high frequency of landslide occurrence. In order to predict the landslide occurrence... Bailongjiang watershed in southern Gansu province, China, is one of the most landslide-prone regions in China, characterized by very high frequency of landslide occurrence. In order to predict the landslide occurrence, a comprehensive map of landslide susceptibility is required which may be significantly helpful in reducing loss of property and human life. In this study, an integrated model of information value method and logistic regression is proposed by using their merits at maximum and overcoming their weaknesses, which may enhance precision and accuracy of landslide susceptibility assessment. A detailed and reliable landslide inventory with 1587 landslides was prepared and randomly divided into two groups,(i) training dataset and(ii) testing dataset. Eight distinct landslide conditioning factors including lithology, slope gradient, aspect, elevation, distance to drainages,distance to faults, distance to roads and vegetation coverage were selected for landslide susceptibility mapping. The produced landslide susceptibility maps were validated by the success rate and prediction rate curves. The validation results show that the success rate and the prediction rate of the integrated model are 81.7 % and 84.6 %, respectively, which indicate that the proposed integrated method is reliable to produce an accurate landslide susceptibility map and the results may be used for landslides management and mitigation. 展开更多
关键词 Landslide susceptibility Integrated model Information value method Logistic regression Bailongjiang watershed
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Energy Balance-Based SWAT Model to Simulate the Mountain Snowmelt and Runoff——Taking the Application in Juntanghu Watershed(China) as an Example 被引量:10
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作者 MENG Xian-Yong YU Dan-Lin LIU Zhi-Hui 《Journal of Mountain Science》 SCIE CSCD 2015年第2期368-381,共14页
In order to predict long-term flooding under extreme weather conditions in central Asia, an energy balance-based distributed snowmelt runoff model was developed and coupled with the Soil and Water Assessment Tool(SWAT... In order to predict long-term flooding under extreme weather conditions in central Asia, an energy balance-based distributed snowmelt runoff model was developed and coupled with the Soil and Water Assessment Tool(SWAT) model. The model was tested at the Juntanghu watershed on the northern slope of the Tian Shan Mountains, Xinjiang,China. We compared the performances of temperature-index method and energy balanced method in SWAT model by taking Juntanghu river basin as an application example(as the simulation experiment was conducted in Juntanghu River, we call the energy balanced method as SWAT-JTH). The results suggest that the SWAT snowmelt model had overall Nash-Sutcliffe efficiency(NSE) coefficients ranging from 0.61 to 0.85 while the physical based approach had NSE coefficients ranging from 0.58 to0.69. Overall, on monthly scale, the SWAT model provides better results than that from the SWAT-JTH model. However, results generated from both methods seem to be fairly close at a daily scale. Thestructure of the temperature-index method is simple and produces reasonable simulation results if the parameters are well within empirical ranges. Although the data requirement for the energy balance method in current observation is difficult to meet and the existence of uncertainty is associated with the experimental approaches of physical processes, the SWAT-JTH model still produced a reasonably high NSE. We conclude that using temperature-index methods to simulate the snowmelt process is sufficient, but the energy balance-based model is still a good choice to simulate extreme weather conditions especially when the required data input for the model is acquired. 展开更多
关键词 SWAT Snowmelt model The physical process Energy balance Temperature-index Water balance
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Spatial and Temporal Changes of Floating Population in China Between 1990 and 2000 被引量:6
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作者 LIU Chen Kuninori OTSUBO +2 位作者 WANG Qinxue Toshiaki ICHINOSE Sadao ISHIMURA 《Chinese Geographical Science》 SCIE CSCD 2007年第2期99-109,共11页
By studying the county-level census data of 1990 and 2000, we analyzed the spatial and temporal changes in the floating population in China between 1990 and 2000. The results of the analysis revealed the following cha... By studying the county-level census data of 1990 and 2000, we analyzed the spatial and temporal changes in the floating population in China between 1990 and 2000. The results of the analysis revealed the following characteris- tics. First, the spatial distribution of the migrants (referred to as 'floaters' in this paper) became increasingly concentrated in the cities during the 1990s. Second, the number of floaters increased rapidly during this period, and the area in which the floaters settled expanded quickly into four population explosion belts: the coast, the Changjiang River Delta, the Beijing-Guangzhou Railway and national border belts. Third, the number of inter-province floaters increased rapidly and exceeded that of intra-province floaters in the 1990s. In addition, to obtain a quantitative relationship between the number of floaters and 10 socio-economic variables by using statistical methods and also to find the chiefly important pulling factors of the migration destination, the authors selected approximately 100 cities with the largest population of floaters. Consequently, we found that four factors-GDP, passenger trips per 10,000 persons, per capita GDP and foreign direct investment-could provide an explanation for 83.7% of the number of floaters in 2000. The GDP showed the highest correlation with the number of floaters, suggesting that a highly developed economy is the most important factor that attracts floaters. Furthermore, a fairly close relationship between the number of floaters and the GDP was also found in 2000 for all the counties. 展开更多
关键词 floating population county-level census spatial and temporal changes China
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Ammonia Volatilization and Nitrogen Utilization Efficiency in Response to Urea Application in Rice Fields of the Taihu Lake Region,China 被引量:66
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作者 LIN De-Xi FAN Xiao-Hui +2 位作者 HU Feng ZHAO Hong-Tao LUO Jia-Fa 《Pedosphere》 SCIE CAS CSCD 2007年第5期639-645,共7页
Ammonia volatilization losses, nitrogen utilization efficiency, and rice yields in response to urea application to a rice field were investigated in Wangzhuang Town, Changshu City, Jiangsu Province, China. The N ferti... Ammonia volatilization losses, nitrogen utilization efficiency, and rice yields in response to urea application to a rice field were investigated in Wangzhuang Town, Changshu City, Jiangsu Province, China. The N fertilizer treatments, applied in triplicate, were 0 (control), 100, 200, 300, or 350 kg N ha^-1. After urea was applied to the surface water, a continuous airflow enclosure method was used to measure ammonia volatilization in the paddy field. Total N losses through ammonia volatilization generally increased with the N application rate, and the two higher N application rates (300 and 350 kg N ha^-1) showed a higher ratio of N lost through ammonia volatilization to applied N. Total ammonia loss by ammonia volatilization during the entire rice growth stage ranged from 9.0% to 16.7% of the applied N. Increasing the application rate generally decreased the ratio of N in the seed to N in the plant. For all N treatments, the nitrogen fertilizer utilization efficiency ranged from 30.9% to 45.9%. Surplus N with the highest N rate resulted in lodging of rice plants, a decreased rate of nitrogen fertilizer utilization, and reduced rice yields. Calculated from this experiment, the most economical N fertilizer application rate was 227 kg ha^-1 for the type of paddy soil in the Taihu Lake region. However, recommending an appropriate N fertilizer application rate such that the plant growth is enhanced and ammonia loss is reduced could improve the N utilization efficiency of rice. 展开更多
关键词 ammonia volatilization N application rate N utilization efficiency paddy soil rice yield
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The Form and Comparison of Value between China and Western Countries 被引量:3
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作者 明虹 《Sino-US English Teaching》 2007年第3期70-72,共3页
Value is a criterion which can help people to distinguish good and bad, beauty and ugliness, fight and wrong and true and false. Value varies from different counties, which is the main cause of the conflict and misund... Value is a criterion which can help people to distinguish good and bad, beauty and ugliness, fight and wrong and true and false. Value varies from different counties, which is the main cause of the conflict and misunderstanding in communication between China and western countries. It is first introduced in this paper about how these differences are formed and then explain them in several ways. It is of great significance to know and learn the cultural differences in cross-cultural communication. 展开更多
关键词 CULTURE VALUE DIFFERENCE
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Climate Change and Its Effects on Runoff of Kaidu River, Xinjiang, China:A Multiple Time-scale Analysis 被引量:33
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作者 XU Jianhua CHEN Yaning +1 位作者 JI Minhe LU Feng 《Chinese Geographical Science》 SCIE CSCD 2008年第4期331-339,共9页
This paper applied an integrated method combining grey relation analysis, wavelet analysis and statistical analysis to study climate change and its effects on runoff of the Kaidu River at multi-time scales. Major find... This paper applied an integrated method combining grey relation analysis, wavelet analysis and statistical analysis to study climate change and its effects on runoff of the Kaidu River at multi-time scales. Major findings are as follows: 1) Climatic factors were ranked in the order of importance to annual runoff as average annual temperature, average temperature in autumn, average temperature in winter, annual precipitation, precipitation in flood season, average temperature in summer, and average temperature in spring. The average annual temperature and annual precipi- tation were selected as the two representative factors that impact the annual runoff. 2) From the 32-year time scale, the annual runoff and the average annual temperature presented a significantly rising trend, whereas the annual precipita- tion showed little increase over the period of 1957-2002. By changing the time scale from 32-year to 4-year, we ob- served nonlinear trends with increasingly obvious oscillations for annual runoff, average annual temperature, and annual precipitation. 3) The changes of the runoff and the regional climate are closely related, indicating that the runoff change is the result of the regional climate changes. With time scales ranging from 32-year, 16-year, 8-year and to 4-year, there are highly significant linear correlations between the annual runoff and the average annual temperature and the annual precipitation. 展开更多
关键词 RUNOFF temperature PRECIPITATION nonlinear trend time scale Kaidu River
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A community-based epidemiological study of elevated serum alanine aminotransferase levels in Kinmen, Taiwan 被引量:3
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作者 Chi-MingLiu Tao-HsinTung +4 位作者 Jorn-HonLiu VictorTze-KaiChen Ching-HengLin Chung-TeHsu PesusChou 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第11期1616-1622,共7页
AIM: To explore any gender-related differences in prevalence of and condition-associated factors related to an elevated serum alanine aminotransferase (ALT) level amongst residents of Kinmen, Taiwan. METHODS: A total ... AIM: To explore any gender-related differences in prevalence of and condition-associated factors related to an elevated serum alanine aminotransferase (ALT) level amongst residents of Kinmen, Taiwan. METHODS: A total of 11 898 of a potential 20 112 regional residents aged 30 years or more completed a related questionnaire that was carried out by the Yang-Ming Crusade between 1991 and 1994 inclusively, with blood samples being collected by public nurses. The overall questionnaire response rate was 59.3% (52.4% for males and 66.0% for females). RESULTS: The prevalence of an elevated serum ALT level for this sub-population was found to be 7.2%, the prevalence revealing a statistically significant decrease with increasing population age (P<0.0001). Males exhibited a greater prevalence of elevated serum ALT level than did females (9.4% vs 5.3%, P<0.0001). Using multiple logistic regression analysis, in addition to male gender, a younger age, greater waist circumference, presence of type-2 diabetes and hyperuricemia were the significant factors associated with an elevated serum ALT level for both males and females. Gender-related differences as regards associated factors were also revealed. For males, obesity was significantly related to an elevated serum ALT level (OR = 1.28, 95%CI: 1.00-1.66) but this was not so for females (OR = 1.09, 95%CI: 0.84-1.42). Hypertriglyceridemia (OR = 1.80, 95%CI: 1.36-2.39) and hyperuricemia (OR = 1.61, 95%CI: 1.03-2.52) were significantly related to elevated serum ALT levels only for females. CONCLUSION: Several gender-related differences were noted pertaining to the prevalence of and relationship between obesity, hypertriglyceridemia and hyperuricemia and elevated serum ALT level in the present study. 展开更多
关键词 Alanine aminotransferase PREVALENCE Community-based study Gender difference
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Multiple Time Scale Analysis of River Runoff Using Wavelet Transform for Dagujia River Basin, Yantai, China 被引量:10
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作者 LIU Delin LILT Xianzhao +2 位作者 LI Bicheng ZHAO Shiwei LI Xiguo 《Chinese Geographical Science》 SCIE CSCD 2009年第2期158-167,共10页
Based on monthly river runoff and meteorological data, a method of Morlet wavelet transform was used to analyze the multiple time scale characteristics of river runoff in the Dagujia River Basin, Yantai City, Shandong... Based on monthly river runoff and meteorological data, a method of Morlet wavelet transform was used to analyze the multiple time scale characteristics of river runoff in the Dagujia River Basin, Yantai City, Shandong Province. The results showed that the total annual river runoffin the Dagujia River Basin decreased significantly from 1966 to 2004, and the rate of decrease was 48× 10^6ma/10yr, which was higher than the mean value of most rivers in China. Multiple time scale characteristics existed, which accounted for different aspects of the changes in annual river runoff, and the major periods of the runofftime series were identified as about 28 years, 14 years and 4 years with decreasing levels of fluctuation. The river runoff evolution process was controlled by changes in precipitation to a certain extent, but it was also greatly influenced by human activities. Also, for different time periods and scales, the impacts of climate changes and human activities on annual river runoff evolution occurred at the same time. Changes in the annual river runoffwere mainly associated with climate change before the 1980s and with human activities after 1981. 展开更多
关键词 multiple time scale river runoff climate change Morlet wavelet transform Dagujia River
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A Modified Groundwater Module in SWAT for Improved Streamflow Simulation in a Large, Arid Endorheic River Watershed in Northwest China 被引量:6
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作者 JIN Xin HE Chansheng +1 位作者 ZHANG Lanhui ZHANG Baoqing 《Chinese Geographical Science》 SCIE CSCD 2018年第1期47-60,共14页
Interactions between surface water and groundwater are dynamic and complex in large endorheic river watersheds in Northwest China due to the influence of both irrigation practices and the local terrain. These interact... Interactions between surface water and groundwater are dynamic and complex in large endorheic river watersheds in Northwest China due to the influence of both irrigation practices and the local terrain. These interactions interchange numerous times throughout the middle reaches, making streamflow simulation a challenge in endorheic river watersheds. In this study, we modified the linear-reservoir groundwater module in SWAT(Soil and Water Assessment Tools, a widely used hydrological model) with a new nonlinear relationship to better represent groundwater processes; we then applied the original SWAT and modified SWAT to the Heihe River Watershed, the second largest endorheic river watershed in Northwest China, to simulate streamflow. After calibrating both the original SWAT model and the modified SWAT model, we analyzed model performance during two periods: an irrigation period and a non-irrigation period. Our results show that the modified SWAT model with the nonlinear groundwater module performed significantly better during both the irrigation and non-irrigation periods. Moreover, after comparing different runoff components simulated by the two models, the results show that, after the implementation of the new nonlinear groundwater module in SWAT, proportions of runoff components changed-and the groundwater flow had significantly increased, dominating the discharge season. Therefore, SWAT coupled with the non-linear groundwater module represents the complex hydrological process in the study area more realistically. Moreover, the results for various runoff components simulated by the modified SWAT models can be used to describe the hydrological characteristics of lowland areas. This indicates that the modified SWAT model is applicable to simulate complex hydrological process of arid endorheic rivers. 展开更多
关键词 Soil and Water Assessment Tools (SWAT) GROUNDWATER irrigation streamflow Heihe River
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Effect of Oxalic Acid on Potassium Release from Typical Chinese Soils and Minerals 被引量:4
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作者 TU Shu-Xin GUO Zhi-Fen SUN Jin-He 《Pedosphere》 SCIE CAS CSCD 2007年第4期457-466,共10页
Oxalic acid plays an important role in improving the bioavailability of soil nutrients. Batch experiments were employed to examine the influences of oxalic acid on extraction and release kinetics of potassium (K) fr... Oxalic acid plays an important role in improving the bioavailability of soil nutrients. Batch experiments were employed to examine the influences of oxalic acid on extraction and release kinetics of potassium (K) from soils and minerals along with the adsorption and desorption of soil K^+. The soils and minerals used were three typical Chinese soils, black soil (Mollisol), red soil (Ultisol), and calcareous alluvial soil (Entisol), and four K-bearing minerals, biotite, phlogopite, muscovite, and microcline. The results showed that soil K extracted using 0.2 mol L^-1 oxalic acid was similar to that using 1 mol L^-1 boiling HNO3. The relation between K release (y) and concentrations of oxalic acid (c) could be best described logarithmically as y = a + blogc, while the best-fit kinetic equation of K release was y = a + b√t, where a and b are the constants and t is the elapsed time. The K release for minerals was ranked as biotite 〉 phlogopite 〉〉 muscovite 〉 microcline and for soils it was in the order: black soil 〉 calcareous alluvial soil 〉 red soil. An oxalic acid solution with low pH was able to release more K from weathered minerals and alkaline soils. Oxalic acid decreased the soil K^+ adsorption and increased the soil K^+ desorption, the effect of which tended to be greater at lower solution pH, especially in the red soil. 展开更多
关键词 Chinese soils K^+ adsorption and desorption K-bearing minerals K release oxalic acid
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