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The Application of Visual Organization Principle in the Detection of Sleep Spindles
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作者 Xuemei Jin Junzhong Zou Jian Zhang 《Journal of Biomedical Science and Engineering》 2017年第5期1-9,共9页
In order to detect the sleep spindles simply and efficiently, a novel time-domain approach to detect sleep spindles based on the principles of visual organization is proposed. The code idea of the visual organization ... In order to detect the sleep spindles simply and efficiently, a novel time-domain approach to detect sleep spindles based on the principles of visual organization is proposed. The code idea of the visual organization is to organize the primary visual elements according to some rules of organization, and to form a more meaningful object of visual processing, as the input of next process. After the collected EEG is processed with the merging algorithm based on the principle of visual organization, it can extract the time-domain feature frequency and duration time better. Use these features with a simple algorithm to detect spindles achieving sensitivity of 92.5% and specificity of 98.1%, which verifies the validity of this method to detect the sleep spindles. 展开更多
关键词 SLEEP SPINDLES principle of VISUAL organization Time-Domain DETECTION
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Remarks on interpretations of the Eotvos experiment and misinterpretation of E=mc^2 被引量:1
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作者 鲁重贤 《Chinese Physics B》 SCIE EI CAS CSCD 2007年第3期635-639,共5页
The Eotvos experiment on the verification of equivalence between inertial mass and gravitational mass of a body is famous for its accuracy. A question is, however, can these experimental results be applied to the case... The Eotvos experiment on the verification of equivalence between inertial mass and gravitational mass of a body is famous for its accuracy. A question is, however, can these experimental results be applied to the case of a physical space in general relativity, where the space coordinates could be arbitrary? It is pointed out that it can be validly applied because it has been proven that Einstein's equivalence principle for a physical space must have a frame of reference with the Euclidean-like structure. Will claimed further that such an overall accuracy can be translated into an accuracy of the equivalence between inertial mass and each type of energy. It is shown that, according to general relativity, such a claim is incorrect. The root of this problem is due to an inadequate understanding of special relativity that produced the famous equation E=mc^2, which must be understood in terms of energy conservation. Concurrently, it is pointed out that this error is a problem in Will's book, ‘Theory and Experiment in Gravitational Physics'. 展开更多
关键词 Einstein's equivalence principle Einstein-Minkowski condition Euclidean-like structure Eotvos experiment weak equivalence principle E=MC^2
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Crop yields and soil organic carbon dynamics in a long-term fertilization experiment in an extremely arid region of northern Xinjiang, China 被引量:1
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作者 LYU Jinling LIU Hua +3 位作者 WANG Xihe Rodrigo OLAVE TIAN Changyan LIU Xuejun 《Journal of Arid Land》 SCIE CSCD 2017年第3期345-354,共10页
A long-term fertilization experiment was set up in northern Xinjiang, China to evaluate the dynamics of crop production and soil organic carbon (SOC) from 1990 to 2012 with seven fertilization treatments. The seven ... A long-term fertilization experiment was set up in northern Xinjiang, China to evaluate the dynamics of crop production and soil organic carbon (SOC) from 1990 to 2012 with seven fertilization treatments. The seven treatments included an unfertilized control (CK) and six different combinations of phosphorus (P), potassium (K), nitrogen (N), straw (S) and animal manure (M). The balanced fertilization treatments had significantly (P〈0.05) higher average yields than the unbalanced ones. The treatment with 2/3 N from potassium sulfate (NPK) and 1/3 N from farmyard manure (NPKM) had a higher average yield than the other treatments. The average yields (over the 23 years) in the treatments of NPK, and urea, calcium superphosphate (NP) did not differ significantly (P〉0.05) but were higher than that in the treatment with urea and potassium sulfate (NK; P〈0.05). The results also show that the highest increases in SOC (P〈0.05) occurred in NPKM with a potential increase of 1.2 t C/(hm2.a). The increase in SOC was only 0.31, 0.30 and 0.12 t C/(hm2.a) for NPKS (9/10 N from NPK and 1/10 N from straw), NPK and NP, respectively; and the SOC in the NP, NK and CK treatments were approaching equilibrium and so did not rise or fall significantly over the 23-year experiment. A complete NPK plus manure fertilization program is recommended for this extremely arid region to maximize both yields and carbon sequestration. 展开更多
关键词 long-term fertilization experiment extremely arid conditions soil organic carbon organic C inputs XINJIANG
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Application and Practice of Knowledge Graph in Experimental Teaching in Colleges and Universities
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作者 Yongming YANG Yan YU +6 位作者 Dongfang TU Shengwei YAO Wei ZHANG Shuangyuan WANG Pengyun DUAN Weiyu NI Wencui LIU 《Asian Agricultural Research》 2024年第10期50-53,57,共5页
With the reform of experimental teaching in colleges and universities,the teaching mode of"experimental students as the main body,experimental teachers as the guide"needs to constantly explore new experiment... With the reform of experimental teaching in colleges and universities,the teaching mode of"experimental students as the main body,experimental teachers as the guide"needs to constantly explore new experimental teaching methods.In this paper,knowledge graph is integrated into the experiment of mechanical principle to guide undergraduates to use knowledge graph to analyze and summarize independently in experimental teaching activities,aiming at cultivating undergraduates interest in learning and innovative thinking,so as to improve the quality of experimental teaching.This study has a certain reference significance for experimental teaching in colleges and universities. 展开更多
关键词 experimental students as the main body and experimental teachers as the guide Knowledge graph Mechanical principle experiment
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Kolmogorov’s Probability Spaces for “Entangled” Data-Subsets of EPRB Experiments: No Violation of Einstein’s Separation Principle 被引量:1
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作者 Karl Hess 《Journal of Modern Physics》 2020年第5期683-702,共20页
It is demonstrated that the use of Kolmogorov’s probability theory to describe results of quantum probability for EPRB (Einstein-Podolsky-Rosen-Bohm) experiments requires extreme care when different subsets of measur... It is demonstrated that the use of Kolmogorov’s probability theory to describe results of quantum probability for EPRB (Einstein-Podolsky-Rosen-Bohm) experiments requires extreme care when different subsets of measurement outcomes are considered. J. S. Bell and his followers have committed critical inaccuracies related to spin-gauge and probability measures of such subsets, because they use exclusively a single probability space for all data sets and sub-sets of data. It is also shown that Bell and followers use far too stringent epistemological requirements for the consequences of space-like separation. Their requirements reach way beyond Einstein’s separation principle and cannot be met by the major existing physical theories including relativity and even classical mechanics. For example, the independent free will does not empower the experimenters to choose multiple independent spin-gauges in the two EPRB wings. It is demonstrated that the suggestion of instantaneous influences at a distance (supposedly “derived” from experiments with entangled quantum entities) is a consequence of said inaccuracies and takes back rank as soon as the Kolmogorov probability measures are related to a consistent global spin-gauge and permitted to be different for different data subsets: Using statistical interpretations and different probability spaces for certain subsets of outcomes instead of probability amplitudes related to single quantum entities, permits physical explanations without a violation of Einstein’s separation principle. 展开更多
关键词 Bell’s theorem Einstein’s Separation principle EPRB experiments
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Simulation Experiments and Kinetics for the Formation of Organic Sulfide in Marine Carbonate Reservoirs
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作者 Changtao Yue Shuyuan Li Yonghan Zhang 《Open Journal of Geology》 2012年第2期65-71,共7页
Thermal simulation experiments on the system of gasoline and magnesium sulfate were carried out using an autoclave operating at high temperature and high pressure in the presence of water. Properties of the gas-oil-so... Thermal simulation experiments on the system of gasoline and magnesium sulfate were carried out using an autoclave operating at high temperature and high pressure in the presence of water. Properties of the gas-oil-solid 3-phase products were analyzed by some advanced analytical methods including gas chromatography, microcoulometry, capillary gas chromatography in combination with a pulsed flame photometric detector, FT-IR and X-ray diffraction. The results showed that the reaction could proceed at 450℃ - 550℃ to produce MgO, S, C, H2S, CO2 and a series of organic sulfides such as mercaptans, sulfoethers and thiophenes as the main products. According to the reaction kinetics, the calculated activation energy of the reaction is 68.9 kJ·mol-1. 展开更多
关键词 Organic SULFIDE GASOLINE MAGNESIUM SULFATE Simulation experiment KINETICS
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Experimental Simulation Study of the Dominant Enrichment Area of Terrestrial Organic Matter in the Shallow-Delta Sedimentary System of the Yacheng Formation in the Qiongdongnan Basin
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作者 XU Xinde YANG Xibing +3 位作者 QU Tong GAO Gang LIANG Gang LI Xing 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2022年第5期1693-1703,共11页
Shallow-delta sedimentary systems receive both terrestrial and marine organic matter. As oil and gas exploration activities determine that the source rocks of the deep-water area of the Qiongdongnan Basin, northern So... Shallow-delta sedimentary systems receive both terrestrial and marine organic matter. As oil and gas exploration activities determine that the source rocks of the deep-water area of the Qiongdongnan Basin, northern South China Sea, are generally rich in and even dominated by terrestrial organic matter, this has led many researchers to examine the rules governing terrestrial organic matter enrichment in shallow-delta sea sedimentary systems. However, the deep burial of source rocks in deep-water areas and the relatively small amount of drilling undertaken have greatly restricted the study of these rules. In this study, the ‘forward modeling' research method was used to observe and analyze the deposition and preservation of terrestrial organic matter through flume experiments, where the depositional results were carefully depicted and sampled. The total organic carbon content of selected samples was measured and when combined with qualitative observations and quantitative comparison results, the dominant enrichment areas of terrestrial organic matter were identified. The experimental results show that the overbank parts of the delta front, the dune countercurrent surface, the low-lying parts, the delta front slope area and the shallow-prodelta sea area are where terrestrial organic matter is predominantly enriched. This provides an important basis and guidance for the prediction of the development areas of marine source rocks with terrestrial input in the deep-water areas of the Qiongdongnan Basin. 展开更多
关键词 shallow-delta sea sedimentary system deep water area terrestrial organic matter flume experiment enrichment area Qiongdongnan Basin
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Categories of Nonlocality in EPR Theories and the Validity of Einstein’s Separation Principle as Well as Bell’s Theorem
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作者 Karl Hess 《Journal of Modern Physics》 2019年第10期1209-1221,共13页
Work on quantum entanglement is currently emphasizing the nonlocal nature of theories that attempt to explain spatially separated Einstein-Podolsky-Rosen (EPR) correlation experiments. It is frequently claimed that no... Work on quantum entanglement is currently emphasizing the nonlocal nature of theories that attempt to explain spatially separated Einstein-Podolsky-Rosen (EPR) correlation experiments. It is frequently claimed that nonlocal instantaneous influences, or equivalently a breakdown of Einstein’s separation principle, are a signature property of (quantum) entanglement. This paper presents a categorization of the various forms of nonlocality in physical theories. It is shown that, even for Einstein’s theory of relativity, correlations of spatially separated measurements cannot be explained without the involvement of some nonlocal or global knowledge and facts. Instantaneous Influences at a distance are, however, in a special category of nonlocality and, as is well known, Einstein called them spooky. Following a separation of nonlocalities into four distinctly different categories 0, 1, 2, 3, with number 3 corresponding to theories containing instantaneous influences at a distance, I show that any theory of EPR experiments must be at least in category 1 or 2 and does not need to be in category 3. In particular, the Bell theorem, valid for category 0 theories, may be violated for categories 1 and 2 and does not require category 3 theories. Category 0 enforces Bell’s theorem. However, it does not apply to relativistic theories of space like separated measurements. 展开更多
关键词 Bell’s theOREM Einstein’s Separation principle EPRB experiments
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Developing Integrated Collective Bargaining System in a Bi National Organization:The Case of the Tanzania Zambia Railway Authority(TAZARA)
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作者 Mwansa Kamukwamba 《Chinese Business Review》 2020年第4期120-130,共11页
The Tanzania Zambia Railway stretches 1,860 kilometers from the East African Indian Ocean port of Dar es Salaam in Tanzania to New Kapiri-Mposhi in land locked Zambia.It is defined as a bi-national organization as opp... The Tanzania Zambia Railway stretches 1,860 kilometers from the East African Indian Ocean port of Dar es Salaam in Tanzania to New Kapiri-Mposhi in land locked Zambia.It is defined as a bi-national organization as opposed to either transnational or multinational because it is jointly owned and managed by the Governments of Tanzania and Zambia.Its construction was made possible by Chinese interest-free loan to the two Governments.Few development projects in Africa have been charged with as much political and ideological dynamite as Tanzania Zambia Railway.To the Western powers,angry that the Chinese had entered territory which they considered their own preserve,it was a Red Railway intended to thrust communism into the very heart of Africa.For the white regimes in Southern Africa,grimly attempting to hold back demands for majority rule,it was seen as Africa’s Ho Chi Minh Trail,carrying guerrilla further,armed with Chinese thoughts and weapons to the banks of the Zambezi River.The Chinese regarded the project as a Friendship Route to strengthen the new African states against the forces of imperialism and for Tanzania and Zambia it was a Freedom Railway,which should prove an instrument in increasing their independence.These reactions underpin not only the complexity of the establishment and management of a bi-national organization but also present challenges to the two national trade unions on how best they can represent their members.Industrial relations literature has cited differences in countries’historical,social,political,economic,and ideological background as the main obstacles in the development of collective bargaining machinery in transnational or multinational organizations.A study in Tanzania Zambia Railway Authority has attempted to develop an integrated bi-national collective bargaining machinery whose collective agreements are likely to be legally enforceable in their respective countries.This paper explores the development of trade unions in both Tanzania and Zambia which can be divided in three phases:first,the construction phase;second,the consolidation phase;and the third and final phase,trade union liberalization and political pluralism which covers the development of a bi national collective bargaining model with its Joint Industrial Council structure and negotiation procedures.The paper compares and contrasts trade union development in the two contracting states and critically examines how each phase has influenced trade union development.It provides a brief historical outline of collective bargaining process and spells out advantages and limitations of bi-national collective bargaining machinery.The paper concludes by observing that one of the main objectives of regional groupings is economic integration and suggests that integrated collective bargaining machinery be adopted as an ideal industrial relations model for regional groupings such as the African Union(AU),Southern African Development Community(SADC),Common Market for Eastern and Southern Africa(COMESA),Economic Community for West African States(ECOWAS),Eastern African Community,and other regional groupings around the world since it localizes industrial relations function in general and collective bargaining in particular. 展开更多
关键词 Bi-national organization Interest free loan British imperial experience Unilateral declaration of independence Integrated collective bargaining ideological dynamite Contracting states economic exploitation
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Generativity of Self-Organizing Processes and Their Correlative Description in Terms of a Formal Language of Meta-Ordinal Generative Nature, in the Light of the Maximum Ordinality Principle and the Explicit Solution to the “Three-Body Problem”
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作者 Corrado Giannantoni 《Journal of Applied Mathematics and Physics》 2023年第10期3159-3202,共44页
The main objective of this paper is to demonstrate that the internal processes of Self-Organizing Systems represent a unique and singular process, characterized by their specific generativity. This process can be mode... The main objective of this paper is to demonstrate that the internal processes of Self-Organizing Systems represent a unique and singular process, characterized by their specific generativity. This process can be modeled using the Maximum Ordinality Principle and its associated formal language, known as the “Incipient” Differential Calculus (IDC). 展开更多
关键词 Maximum Ordinality principle Solution to the “Three-Body Problem” Generativity of Self-Organizing Processes Formal Language of Ordinal Generativity Formal Language of Meta-Ordinal Generativity
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Changes of Organic Matter, N, P and K Content of Soils in Red Soil Areas Under Long-Term Experiment 被引量:9
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作者 JIANG Duan-sheng ZENG Xi-bai +1 位作者 GAO Ju-sheng LI Lian-fang 《Agricultural Sciences in China》 CAS CSCD 2008年第7期853-859,共7页
The content of organic matter (OM), nitrogen (N), phosphorus (P), and potassium (K) in the three selected soils, including Calcaric Purpli-Orthic Primosols (purple sand-shale parent material), Dystric Turbi-... The content of organic matter (OM), nitrogen (N), phosphorus (P), and potassium (K) in the three selected soils, including Calcaric Purpli-Orthic Primosols (purple sand-shale parent material), Dystric Turbi-Anthric Primosols (quaternary red clay parent material) and Typic Udi-Sandic Primosols (granite parent material) were studied under a long-term experiment by using crop straw and inorganic fertilizers at the Hunan Red Soil Experiment Station of Chinese Academy of Agricultural Sciences. The results showed that the contents of OM, N, P and K in the three selected soils increased after 23 years application of crop straw and inorganic fertilizers, but the contents increased much less when crop straw or inorganic fertilizers was applied alone. The nutrient contents in the three soils developed from granite changed more remarkably than those in the soil derived from quaternary red clay and purple sand-shale. It was also found that the contents of OM, N, and P increased slightly in the treatments without applying fertilizers or returning the crop straw to the root bed. Combined application of inorganic fertilizers and crop straw could remarkably increase the contents of OM, alkalihydrolyzable N and available K, the positive correlation between application of organic fertilizers and increase of OM in soil did not always happened, it provided evidence for the relation between appropriate C/N ratio and accumulation of OM in soil. The increase of nutrient content was influenced by the soil properties. By comparing the contents of nutrient in 0-20 cm depth in the three different soils, it was concluded that the most increases of OM, alkali-hydrolyzable N, and available P were observed in Typic Udi-Sandic Primosols with the average increase by 3.03, 27.38, and 21.73 mg kg^-1, respectively. The available K increased in Dystric Turbi-Anthric Primosols with the average increase by 25.82 mg kg^-1, while it decreased in Calcaric Purpli-Orthic Primosols and Typic Udi-Sandic Primosols. It was concluded that the application of inorganic fertilizer and crop straw was important to improve the soil fertility for all of three selected soils. The straw return to the field had played a significant role for enhancement of the soil quality in the study areas. The application of inorganic fertilizer combined with the straw return to the fields could remarkably improve the soil fertility. 展开更多
关键词 organic matter inorganic fertilizers NUTRIENT crop straw long-term experiment
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Effects of long-term fertilization on soil gross N transformation rates and their implications 被引量:3
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作者 DAI Shen-yan WANG Jing +2 位作者 CHENG Yi ZHANG Jin-bo CAI Zu-cong 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第12期2863-2870,共8页
Application of fertilizer has been found to significantly affect soil N cycling. However, a comprehensive understanding of the effects of long-term fertilization on soil gross N transformation rates is still lacking. ... Application of fertilizer has been found to significantly affect soil N cycling. However, a comprehensive understanding of the effects of long-term fertilization on soil gross N transformation rates is still lacking. We compiled data of observations from 10 long-term fertilization experiments and conducted a meta-analysis of the effects of long-term fertilization on soil gross N transformation rates. The results showed that if chemical fertilizers of N, P and K were applied in balance, soil p H decreased very slightly. There was a significantly positive effect of long-term fertilization, either chemical or organic fertilizers or their combinations, on gross N mineralization rate compared to the control treatment(the mean effect size ranged from 1.21 to 1.25 at 95% confidence intervals(CI) with a mean of 1.23), mainly due to the increasing soil total N content. The long-term application of organic fertilizer alone and combining organic and chemical fertilizer could increase the mineralization-immobilization turnover, thus enhance available N for plant while reduce N losses potential compared to the control treatment. However, long-term chemical fertilizer application did not significantly affect the gross NH4+ immobilization rate, but accelerated gross nitrification rate(1.19; 95% CI: 1.08 to 1.31). Thus, long-term chemical fertilizer alone would probably induce higher N losses potential through NO3– leaching and runoff than organic fertilizer application compared to the control treatment. Therefore, in the view of the effects of long-term fertilization on gross N transformation rates, it also supports that organic fertilizer alone or combination of organic and chemical fertilizer could not only improve crop yield, but also increase soil fertility and reduce the N losses potential. 展开更多
关键词 chemical fertilizer organic fertilizer gross N transformation rate long-term fertilization experiment META-ANALYSIS
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Second organic aerosol formation from the ozonolysis of α-pinene in the presence of dry submicron ammonium sulfate aerosol 被引量:2
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作者 ZHAO Zhe HAO Jiming +1 位作者 LI Junhua WU Shan 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第10期1183-1188,共6页
An indoor chamber facility is described for investigation of atmospheric aerosol chemistry. Two sets of α-pinene ozonolysis experiments were conducted in the presence of dry ammonium sulfate seed particle: ozone limi... An indoor chamber facility is described for investigation of atmospheric aerosol chemistry. Two sets of α-pinene ozonolysis experiments were conducted in the presence of dry ammonium sulfate seed particle: ozone limited experiments and α-pinene limited experiments. The concentration of gas phase and particle phase species was monitored continuously by on-line instruments and recorded automatically by data sampling system. The evolution of size distribution was measured by a scanning mobility particle sizer ... 展开更多
关键词 α-pinene ozonolysis secondary organic aerosol (SOA) chamber experiment seed particles
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An Efficient Grid Service Discovery Mechanism Based on the Locality Principle 被引量:2
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作者 KOU Yue YU Ge SHEN De-rong NIE Tie-zheng LIU Jian CAO Yu 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第1期83-87,共5页
With the explosion of services in grid environment, it's necessary to develop a mechanism which has the ability of discovering suitable grid services efficiently. This paper attempts to establish a layered resource m... With the explosion of services in grid environment, it's necessary to develop a mechanism which has the ability of discovering suitable grid services efficiently. This paper attempts to establish a layered resource management model based on the locality principle which classifies services into different domains and virtual organizations (VOs) according to their shared purposes. We propose an ontologybased search method applying the ontology theory for characterizing semantic information. In addition, we extend the UD- D1 in querying, storing, and so on. Simulation experiments have shown that our mechanism achieves higher performance in precision, recall and query response time. 展开更多
关键词 grid service discovery locality principle virtual organization ontology semantic information UDDI(universal description discovery and integration)
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Effects of Organic Enrichment on Sandy Beach Meiofauna:A Laboratory Microcosm Experiment 被引量:2
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作者 WANG Jianing ZHOU Hong ZHANG Zhinan CONG Bingqing XU Shuhui 《Journal of Ocean University of China》 SCIE CAS 2011年第3期246-254,共9页
Meiofauna samples from intertidal sediments of Qingdao No.2 Bathing Beach, China, were collected for field study, and subjected to organic enrichment in a laboratory microcosm experiment for 21 d. There were three dif... Meiofauna samples from intertidal sediments of Qingdao No.2 Bathing Beach, China, were collected for field study, and subjected to organic enrichment in a laboratory microcosm experiment for 21 d. There were three different treatments including non-organic addition as the control, low-organic enrichment (2 g DW green algae per 150 mL) and high-organic enrichment (10 g DW green algae per 150 mL). After 21 d, the meiofauna richness decreased in both organic enrichment treatments. Among the three treatments, total meiofauna abundance was significantly different, and the control groups had higher abundance than the other two treatment groups. However, the responses of the meiofauna abundance in the two organic enrichment treatments were non-significantly different. The relationship of meiofaunal abundance and nematode/copepod ratios to organic matter and oxygen level in the microcosm experiments were discussed. 展开更多
关键词 organic enrichment MEIofAUNA NEMATODE ABUNDANCE microcosm experiment
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The efficiency of long-term straw return to sequester organic carbon in Northeast China's cropland 被引量:23
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作者 WANG Shi-chao ZHAO Ya-wen +5 位作者 WANG Jin-zhou ZHU Ping CUI Xian HAN Xiao-zeng XU Ming-gang LU Chang-ai 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2018年第2期436-448,共13页
Black soil is one of the most precious soil resources on earth because it has abundant carbon stocks and a relatively high production capacity. However, decreasing organic matter after land reclamation, and the effect... Black soil is one of the most precious soil resources on earth because it has abundant carbon stocks and a relatively high production capacity. However, decreasing organic matter after land reclamation, and the effects of long-term inputs of organic carbon have made it less fertile black soil in Northeast China. Straw return could be an effective method for improving soil organic carbon(SOC) sequestration in black soils. The objective of this study was to evaluate whether straw return effectively increases SOC sequestration. Long-term field experiments were conducted at three sites in Northeast China with varying latitudes and SOC densities. Study plots were subjected to three treatments: no fertilization(CK); inorganic fertilization(NPK); and NPK plus straw return(NPKS). The results showed that the SOC stocks resulting from NPKS treatment were 4.0 and 5.7% higher than those from NPK treatment at two sites, but straw return did not significantly affect the SOC stocks at the third site. Furthermore, at higher SOC densities, the NPKS treatment resulted in significantly higher soil carbon sequestration rates(CSR) than the NPK treatment. The equilibrium value of the CSR for the NPKS treatment equated to cultivation times of 17, 11, and 8 years at the different sites. Straw return did not significantly increase the SOC stocks in regions with low SOC densities, but did enhance the C pool in regions with high SOC densities. These results show that there is strong regional variation in the effects of straw return on the SOC stocks in black soil in Northeast China. Additional cultivations and fertilization practices should be used when straw return is considered as an approach for the long-term improvement of the soil organic carbon pool. 展开更多
关键词 soil organic carbon(SOC) SOC stock straw return soil sequestration rate straw-C sequestration efficiency black soil long-term experiments
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锆基MOF光催化制过氧化氢的综合化学实验设计
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作者 任颜卫 翟祺祥 《广东化工》 CAS 2024年第11期176-178,共3页
为了加强科研成果向实验教学转化和培养学生科研创新能力,设计基于金属有机框架(MOF)材料的光催化制过氧化氢(H_(2)O_(2))综合化学实验。以双氨基功能化联苯二甲酸为配体,四氯化锆为金属盐,苯甲酸为调节剂,通过溶剂热法合成锆基MOF催化... 为了加强科研成果向实验教学转化和培养学生科研创新能力,设计基于金属有机框架(MOF)材料的光催化制过氧化氢(H_(2)O_(2))综合化学实验。以双氨基功能化联苯二甲酸为配体,四氯化锆为金属盐,苯甲酸为调节剂,通过溶剂热法合成锆基MOF催化剂UiO-67-(NH_(2))_(2)。利用PXRD和UV-DRS对样品结构和可见光吸收性能进行表征。以蓝光LED为光源,探究光源功率、催化剂浓度和反应时间对光催化制H_(2)O_(2)效率的影响。采用罗丹明B为模拟污染物,验证所制H_(2)O_(2)溶液的降解污染物性能。该综合实验涉及MOF合成及表征、仪器测试、数据分析等多个环节,不仅加深学生对化学、材料和环境等多学科基础知识的综合理解,还能激发学生的学习积极性和培养学生的创新能力。 展开更多
关键词 综合化学实验 金属有机框架 光催化 过氧化氢 污染物降解
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气态碘在COF-103上吸附的理论研究 被引量:1
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作者 童大银 赵耀林 +4 位作者 王禹齐 韩子彤 王杰 张俊 喻晨曦 《高等学校化学学报》 SCIE EI CSCD 北大核心 2024年第1期84-93,共10页
采用第一性原理和巨正则蒙特卡罗方法,模拟研究了气态碘分子(I2)在共价有机框架材料(COF-103)中的吸附行为,并讨论了气态氧化物、氯化物和挥发性有机化合物(VOCs)等杂质气体的竞争吸附影响.结果表明,I2偏向以垂直方式吸附于COF-103苯环... 采用第一性原理和巨正则蒙特卡罗方法,模拟研究了气态碘分子(I2)在共价有机框架材料(COF-103)中的吸附行为,并讨论了气态氧化物、氯化物和挥发性有机化合物(VOCs)等杂质气体的竞争吸附影响.结果表明,I2偏向以垂直方式吸附于COF-103苯环的碳原子位,其中,长程色散相互作用具有重要的贡献,色散能在吸附能中的占比最多可达46%.I2与COF-103之间存在少量电荷转移,且可能形成具有弱共价相互作用的次级键.杂质气体中苯分子(C6H6)的吸附能和等量吸附热最大,与COF-103的亲和性最强,并且可以占据I2的吸附位点,从而引起I2吸附量的显著降低. 展开更多
关键词 气态碘吸附 共价有机框架 第一性原理 巨正则蒙特卡罗
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Risk assessment of and targeted intervention for falls in the elderly based on the relationship between physical function levels and risk factors for falls
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作者 Susumu Sato Shinichi Demura Masanobu Uchiyama 《Advances in Aging Research》 2013年第3期87-93,共7页
Although fall experience is an important predictor of future falls, clinicians place too much emphasis on this factor during risk assessment of falls. This study aimed to determine individuals with high and low fall r... Although fall experience is an important predictor of future falls, clinicians place too much emphasis on this factor during risk assessment of falls. This study aimed to determine individuals with high and low fall risk on the basis of the relationship between physical function levels [competence in performing activities of daily living (ADL)] and risk factors for falls (fall experience, locomotive organ impairment, and potential for falling). Participants were 1057 independent community-dwelling elderly individuals. ADL competence and the status of risk factors for falls were evaluated using a questionnaire and the relationship between the two was determined. We calculated the cumulative relative frequency curves for ADL scores after categorizing the participants into several groups according to combinations of risk factors and analyzed those combinations that showed wide individual differences in the cumulative relative frequency curves. Intergroup differences when the participants were categorized on the basis of fall experience alone were small;however, those when the participants were categorized on the basis of locomotive impairment and potential for falling were much greater. On classifying the participants into eight groups on the basis of locomotive organ health, fall risk, and fall experience, we found that fallers with locomotive impairment and a high fall risk exhibited the lowest ADL scores while fallers without locomotive impairment and with a low fall risk exhibited the highest ADL scores. Fall risk assessments that are overtly dependent on fall experience are fundamentally limited. Grouping key risk factors can help in determining target groups, including highrisk fallers, low-risk fallers, and high-risk nonfallers, which require primary preventive measures among the community-dwelling elderly. 展开更多
关键词 LOCOMOTIVE ORGAN IMPAIRMENT FALL Experience ADL Competence
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THEORY OF THICK-WALLED SHELLS AND ITS APPLICATION IN CYLINDRICAL SHELL
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作者 房营光 潘纪浩 陈维新 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1992年第11期1055-1065,共11页
In this paper, a theory of thick-walled shells is established by means of Hellinger-Reissner's variational principle, with displacement and stress assumptions. The displacements are expanded into power series of t... In this paper, a theory of thick-walled shells is established by means of Hellinger-Reissner's variational principle, with displacement and stress assumptions. The displacements are expanded into power series of the thickness coordinate. Only the first four and the first three terms are used for the displacements parallel and normal to the middle surface respectively. The normal extruding and transverse shear stresses are assumed to be cubic polynomials and to satisfy the boundary stress conditions on the outer and inner surfaces of the shell. The governing equations and boundary conditions are derived by means of variational principle. As an example, a thick-walled cylindrical shell is disscussed with the theory proposed. Furthermore, a photoelastic experiment has been carried out, and the results are in fair agreement with the computations. 展开更多
关键词 thick-walled shell cylindrical shell normal extruding stress variational principle photoelastic experiment
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