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Soaking Induced Changes in Chemical Composition, Glycemic Index and Starch Characteristics of Basmati Rice 被引量:2
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作者 S.J.KALE S.K.JHA +2 位作者 G.K.JHA J.P.SINHA S.B.LAL 《Rice science》 SCIE CSCD 2015年第5期227-236,共10页
An attempt was made to determine the qualitative changes in basmati rice (Pusa Basmati 1121, PBl121) during soaking at 40 ℃ to 80 ℃. Soaking temperature had significant effect (a = 0.01) on chemical composition,... An attempt was made to determine the qualitative changes in basmati rice (Pusa Basmati 1121, PBl121) during soaking at 40 ℃ to 80 ℃. Soaking temperature had significant effect (a = 0.01) on chemical composition, glycemic index and starch characteristics of rice. Starch content, apparent amylose content, crude protein content and crude fat content in un-soaked rice were found to be 73.24%, 27.26%, 8.79% and 2.56%, respectively, but differences in these traits were observed after soaking. Amylose to amylopectin ratio (Am/Ap) decreased from 0.59 to 0.52 (soaked at 80 ℃). Crude fibre and crude ash contents increased after soaking. The mineral composition (K, P, S, Ca, Mg, Mn, Fe, Cu and Zn) in soaked rice was found to be 16.46% higher than un-soaked rice at the same degree of polishing. Glycemic index of un-soaked rice was found to be 58.41, but decreased to 54.31 after soaking at 80 ℃. Pasting properties, scanning electron microscope images, and X-ray diffractograms suggested partial gelatinization of starch in the temperature range of 60 ℃ to 80 ℃. Based on qualitative changes in rice (apparent amylose content, Am/Ap ratio and crystallinity rate), it was concluded that intermediate soakincl temperatures (60 ℃ to 70 ℃) would be useful for soaking of PB1121. 展开更多
关键词 basmati rice SOAKING glycemic index starch characteristic TEMPERATURE CHEMICALCOMPOSITION CRYSTALLINITY
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Characteristics and Warning Indexes of Rice Seeds Viability Loss During Storage at 45℃ Constant Temperature 被引量:2
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作者 LU Xin-xiong and CHEN Xiao-ling(Key Laboratory for Crop Germplasm and Biotechnology of Agricultural Ministry, Institute of Crop Germplasm Resources, Chinese Academy of Agricultural Sciences, Beijing 100081, P.R.China) 《Agricultural Sciences in China》 CAS CSCD 2002年第8期911-915,共5页
Seed aging characteristics of rice was investigated in this study. Seeds of 34 japonica rice (O-ryza sativa subsp. japonica) varieties were held at 451 constant temperature. Changes in seed viability and seed vigor du... Seed aging characteristics of rice was investigated in this study. Seeds of 34 japonica rice (O-ryza sativa subsp. japonica) varieties were held at 451 constant temperature. Changes in seed viability and seed vigor during aging process were measured to study seed viability-losing characteristic and to determine warning index for seed viability loss. As a result, seed viability survival curves were obtained across different rice accessions at 45℃ constant temperature. The curves appeared to be contra-sigmoid survival curves. The loss of seed viability in the aging process consisted of two phases. The first phase took a long duration, in which the viability of vigorous seeds declined slowly. In the second phase, seed viability declined rapidly. It was obvious that seed viability declined inconsistently during storage. It also showed that seed germination was prolonged and the seedling was significantly weakened before the coming of the rapid declining phase of seed viability. These two parameters could be used to indicate seed quality during storage. The rate of compatibility of tests (RCT), coefficient of variation (CV), vigor of seedling, the day the seeds start to germinate could be used as warning indexes to indicate overall quality of a mass of accessions. These warning indexes could also be used in monitoring the viability of seeds stored in the seed genebank. 展开更多
关键词 Seed viability-loss characteristics Warning indexes Seed viability monitoring Germplasm conservation
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Assessment of Surface Water Quality of King Abdullah Canal, Using Physico-Chemical Characteristics and Water Quality Index, Jordan 被引量:1
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作者 Atef Faleh Al-Mashagbah 《Journal of Water Resource and Protection》 2015年第4期339-352,共14页
The main aim of this research is to evaluate the water quality of King Abdullah Canal (KAC) using the water quality index method (WQI). For this purpose, nine different sampling sites were used in the calculation of W... The main aim of this research is to evaluate the water quality of King Abdullah Canal (KAC) using the water quality index method (WQI). For this purpose, nine different sampling sites were used in the calculation of WQI during the period of January to December 2012. The samples were analyzed for various physico-chemical parameters such as pH, electrical conductivity, total suspended solids, ions of Sodium, Potassium, Calcium, Magnesium, Fluorite, Chloride, Sulfate, Bicarbonate, and Nitrate in different seasons (winter, spring, summer and autumn). The analyzed results (by WQI method) have been used to suggest models for predicting water quality. The relative weight assigned to each parameter has a range from 1 to 5, based on the important parameters for drinking purposes. The computed WQI for the nine samples has a range from 46.66 to 542.08. The analysis reveals that the water quality status of the study area is varying from excellent to good in the upper part of the canal and from poor to very poor in the lower part of the canal. Comparing with the World Health Organization (WHO) and Jordan Standard (JS), the results indicate that the lower part of the canal is polluted. Therefore, the water is not safe for domestic use and needs further treatment, especially in the lower part of the canal. 展开更多
关键词 Water QUALITY index KING Abdullah CANAL PHYSICO-CHEMICAL characteristics JORDAN
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A study on characteristic indexesof railway ballast bed underhigh-frequency radar
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作者 Shilei Wang Zhan Peng +2 位作者 Guixian Liu Weile Qiang Chi Zhang 《Railway Sciences》 2023年第1期33-47,共15页
Purpose–In this paper,a high-frequency radar test system was used to collect the data of clean ballast bed and fouled ballast bed of ballasted tracks,respectively,for a quantitative evaluation of the condition of rai... Purpose–In this paper,a high-frequency radar test system was used to collect the data of clean ballast bed and fouled ballast bed of ballasted tracks,respectively,for a quantitative evaluation of the condition of railway ballast bed.Design/methodology/approach–Based on original radar signals,the time–frequency characteristics of radar signals were analyzed,five ballast bed condition characteristic indexes were proposed,including the frequency domain integral area,scanning area,number of intersections with the time axis,number of timedomain inflection points and amplitude envelope obtained by Hilbert transform,and the effectiveness and sensitivity of the indexes were analyzed.Findings–The thickness of ballast bed tested at the sleep bottom by high-frequency radar is up to 55 cm,which meets the requirements of ballast bed detection.Compared with clean ballast bed,the values of the five indexes of fouled ballast bed are larger,and the five indexes could effectively show the condition of the ballast bed.The computational efficiency of amplitude envelope obtained by Hilbert transform is 140 s$km1,and the computational efficiency of other indexes is 5 s$km1.The amplitude envelopes obtained by Hilbert transform in the subgrade sections and tunnel sections are the most sensitive,followed by scanning area.The number of intersections with the time axis in the bridge sections was the most sensitive,followed by the scanning area.The scanning area can adapt to different substructures such as subgrade,bridges and tunnels,with high comprehensive sensitivity.Originality/value–The research can provide appropriate characteristic indexes from the high-frequency radar original signal to quantitatively evaluate ballast bed condition under different substructures. 展开更多
关键词 Ballasted track Ballast bed High-frequency radar TEST Time–frequency characteristics characteristic indexes
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Thornthwaite moisture index and depth of suction change under current and future climate‒An Australian study
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作者 Md Rajibul Karim Bikash Devkota +1 位作者 Md Mizanur Rahman Hoang Bao Khoi Nguyen 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1761-1775,共15页
Climate change is one of the major global challenges and it can have a significant influence on the behaviour and resilience of geotechnical structures.The changes in moisture content in soil lead to effective stress ... Climate change is one of the major global challenges and it can have a significant influence on the behaviour and resilience of geotechnical structures.The changes in moisture content in soil lead to effective stress changes and can be accompanied by significant volume changes in reactive/expansive soils.The volume change leads to ground movement and can exert additional stresses on structures founded on or within a shallow depth of such soils.Climate change is likely to amplify the ground movement potential and the associated problems are likely to worsen.The effect of atmospheric boundary interaction on soil behaviour has often been correlated to Thornthwaite moisture index(TMI).In this study,the long-term weather data and anticipated future projections for various emission scenarios were used to generate a series of TMI maps for Australia.The changes in TMI were then correlated to the depth of suction change(H s),an important input in ground movement calculation.Under all climate scenarios considered,reductions in TMI and increases in H s values were observed.A hypothetical design scenario of a footing on expansive soil under current and future climate is discussed.It is observed that a design that might be considered adequate under the current climate scenario,may fail under future scenarios and accommodations should be made in the design for such events. 展开更多
关键词 Climate change Future prediction Thornthwaite moisture index(TMI) characteristic surface movement Infrastructure resilience
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INTENSITY INDEX OF SOUTH CHINA SEA MONSOON AND ITS VARIATION CHARACTERISTICS 被引量:2
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作者 吴尚森 梁建茵 《Journal of Tropical Meteorology》 SCIE 2002年第1期1-9,共9页
According to the basic characteristics of the activities of summer monsoon in the South China Sea, a standardized index, sI, has been designed that integrates a dynamic factor (southwesterly component) and a thermodyn... According to the basic characteristics of the activities of summer monsoon in the South China Sea, a standardized index, sI, has been designed that integrates a dynamic factor (southwesterly component) and a thermodynamic factor (OLR) for the indication of summer monsoon in the South China Sea. With the index determined for individual months of June, July and August and the entire summertime from 1975 to 1999, specific months and years are indicated that are either strong or weak in monsoon intensity. The variation is studied for the patterns and sI抯 relationship is revealed with the onset of summer monsoon and the precipitation in Guangdong province and China. The results show that there are quasi-10 and quasi-3-4 year cycles in the interannual variation of the monsoon over the past 25 years. When it has an early (late) onset, the summer monsoon is usually strong (weak). In the strong (weak) monsoon years, precipitation tends to be more (less) in the first raining season of the year but normal or less (normal) in the second, in the province, but it would be more (less) in northeastern China and most parts of the northern China and south of the lower reaches of the Changjiang River and less (more) in the middle and lower reaches of the river, western part of northern China and western China. 展开更多
关键词 南海 夏季风 强度指标 变化特征 热力学 六月 七月 八月 长江流域
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Relationships of Panicle Type Index with Subspecies Characteristics and Yield Traits in Filial Generation of Crosses between Indica and Japonica Rice
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作者 Xu Hai ZHU Chun-jie +7 位作者 Guo Yan-hua Xu Quan MAO Ting CHEN Kai WANG Jia-yu YANG Li ZHENG Jia-kui Xu Zheng-jin 《Rice science》 SCIE 2010年第2期149-155,共7页
Two recombinant inbred line (RIL) populations, one derived from a cross between Zhongyouzao 8 (indica) and Toyonishiki (japonica) and the other from a cross between Qishanzhan (indica) and Akihikari (japonica... Two recombinant inbred line (RIL) populations, one derived from a cross between Zhongyouzao 8 (indica) and Toyonishiki (japonica) and the other from a cross between Qishanzhan (indica) and Akihikari (japonica), were grown in Liaoning and Sichuan Provinces, China, to study the panicle type index (PTI, the ratio of a number of node position on panicle axis where the secondary branch with the most numerous secondary branch grains is located to the number of primary branches) and its relationships with subspecies characteristics and yield traits. With continuous distribution of PTI and numerous of lines with different PTIs in the progenies, indica-japonica hybridization could be a method for breeding cultivars with ideal panicle type. PTI was significantly influenced by environments, with a significant decrease from Liaoning to Sichuan A significantly negative correlation was found between PTI and most of subspecies characteristics. PTI varied remarkably with different subspecies types. As a whole, it showed a trend of indica (H)〉indicalinous (H')〉japonicalinous (K')〉japonica (K) However, it is not appropriate to regard PTI as a parameter for subspecies classification in rice because it was recombined in the filial generations of cross between indica and japonica rice. The negative correlations were found between PTI and most of panicle characteristics, as well as yield-related traits. Based on PTI, most of lines from the two populations were middle dominant panicle type (the number of grains on the secondary branch is numerous in middle position of the panicle) and lower dominant panicle type (the number of grains on the secondary branch is numerous in lower position of the panicle and becomes less towards the top of panicle) with significant yield advantages. 展开更多
关键词 RICE indica-japonica hybridization panicle type index subspecies characteristics yield trait RELATIONSHIP
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Children, Influenza, Encephalopathy, Clinical Characteristics, Laboratory Index
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作者 Qinglian Chen Tianxiang Qiu +2 位作者 Guangming Liu Peiqing Li Hui Lu 《Journal of Behavioral and Brain Science》 2021年第9期227-238,共12页
<i><b>Background:</b></i> To explore the early clinical features and laboratory findings of influenza-associated acute necrotizing encephalopathy (IANE). <i><b>Methods:</i><... <i><b>Background:</b></i> To explore the early clinical features and laboratory findings of influenza-associated acute necrotizing encephalopathy (IANE). <i><b>Methods:</i></b> The demographics data, clinical manifestations, and laboratory indicators of cases diagnosed with IANE and influenza with febrile convulsions (FS), respectively, admitted to Guangzhou Women and Children’s Medical Center from January 2016 to January 2020 were retrospectively analyzed. <i><b>Results:</i></b> Among the 25 cases of IANE, there were 9 males and 16 females, aged 3 to 6 years. The mortality rate was 40.00% (10/25). Influenza virus type A in 9 cases (36.00%) and influenza virus type B in 10 cases (40.00%). The main clinical manifestations of children with IANE were acute disorders of consciousness (64.00%, 16/25) and convulsions (72.00%, 18/25), which were statistically significant when compared with the FS group (P < 0.05). Typical changes on cranial MRI of IANE were cerebral edema, typically with symmetric necrosis of the thalamus and other brain structures. Significant differences (P < 0.05) existed between the IANE and FS groups in laboratory indicators for ALT, AST, CK-MB, LDH, cerebrospinal fluid (CSF) microprotein, CSF LDH, which were above the normal reference range. In addition, logistic regression analysis showed that LDH ≥ 348.5 U/L predicted a significantly higher risk of IANE. <i><b>Conclusions:</i></b> Children with influenza present early with acute impairment of consciousness or convulsive seizures, or with elevated AST, ALT, CK-MB, LDH, and CSF protein and CSF LDH, especially if blood LDH is ≥348.5 U/L, should be closely evaluated and alerted to the possibility of IANE. 展开更多
关键词 CHILDREN INFLUENZA ENCEPHALOPATHY Clinical characteristics Laboratory index
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Neuroelectrophysiological indexes and clinical characteristics of patients with peroneal muscular atrophy: Retrospective analysis of 24 cases
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作者 Changchun Su Qinbao Qin 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第9期821-824,共4页
BACKGROUND: Peroneal muscular atrophy (PMA) is characterized by insidious onset, gradually progressive course of disease, very mild disability degree and easily subjecting to missed diagnosis and misdiagnosis. Nerve c... BACKGROUND: Peroneal muscular atrophy (PMA) is characterized by insidious onset, gradually progressive course of disease, very mild disability degree and easily subjecting to missed diagnosis and misdiagnosis. Nerve conductive velocity is helpful in the diagnosis of atypical cases. OBJECTIVE: To retrospectively analyze the characteristics of clinical manifestation, electromyogram (EMG), motor and sensory nerve conduction velocity of patients with PMA. DESIGN: Retrospective case analysis. SETTING: Department of Neurology, Guangzhou First People's Hospital. PARTICIPANTS: Twenty-four patients with PMA, including 16 males and 8 females, aged 5-68 years old, admitted to Guangzhou First People's Hospital between March 1996 and January 2006 were recruited. Informed consents were obtained from all the patients. METHODS: All the patients subjected to EMG and detection of nerve conduction velocity at distal end of four extremities with a Keypoint evoked potential/ EMG instrument (Denmark). Sensory and motor conduction velocity, EMG changes of upper and lower extremities were observed, and relationship of neuroelectrophysiological characteristics and clinical symptoms was analyzed. MAIN OUTCOME MEASURES: Changes in sensory and motor conduction velocity, EMG and clinical manifestations of 24 patients. RESULTS: ① All the patients suffered from insidious onset and gradually progressive course of PMA. Muscular atrophy of lower extremity was found in 14 patients, and that of upper extremity in 5 patients. ②Routine nerve conduction study showed that sensory and motor conduction velocity were stepped down, especially in 16 patients with typeⅠPMA (demyelinating pattern, nerve conduction velocity below normal level 50%). Motor nerve conduction velocity of median nerve, ulnar nerve, common peroneal nerve and tibial nerve averaged 34.8 m/s, 37.2 m/s, 16.5 m/s and 17.4 m/s, respectively; Sensory nerve conduction velocity of median nerve, ulnar nerve and sural nerve averaged 27.9%, 24.6 m/s and 3.1 m/s, respectively. Slowing conduction velocity and muscular strength involvement were disproportionate, i.e. myasthenia was relatively lessened, sensory and motor conduction velocities were greatly decreased. Nerve conduction velocity in distal end of two lower extremities was not detected in 8 patients, but who could still walk. CONCLUSION: ①PMA of patients is characterized by insidious onset and gradually progressive course of disease. Clinical symptom is the base to diagnose PMA. ②Neuroelectrophysiological study is a simple and easy-to-operate means with good reproducibility in diagnosing PMA. Patients with abnormal myasthenia in lower extremity can be detected in the early stage. 展开更多
关键词 PMA Retrospective analysis of 24 cases Neuroelectrophysiological indexes and clinical characteristics of patients with peroneal muscular atrophy
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Prediction of Abdominal Visceral Obesity From Body Mass Index,Waist Circumference and Waist-hip Ratio in Chinese Adults:Receiver Operating Characteristic Curves Analysis 被引量:54
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作者 WEI-PINGJIA JUN-XILU +3 位作者 KUN-SANXIANG Yu-QIANBAO HUI-JUANLU ANDLEICHEN 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2003年第3期206-211,共6页
Objective To evaluate the sensitivity and specificity of body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR) measurements in diagnosing abdominal visceral obesity. Methods BMI, WC, and WHR wer... Objective To evaluate the sensitivity and specificity of body mass index (BMI), waist circumference (WC) and waist-to-hip ratio (WHR) measurements in diagnosing abdominal visceral obesity. Methods BMI, WC, and WHR were assessed in 690 Chinese adults (305 men and 385 women) and compared with magnetic resonance imaging (MRI) measurements of abdominal visceral adipose tissue (VA). Receiver operating characteristic (ROC) curves were generated and used to determine the threshold point for each anthropometric parameter. Results 1) MRI showed that 61.7% of overweight/obese individuals (BMI≥25 kg/m2) and 14.2% of normal weight (BMI<25 kg/m2) individuals had abdominal visceral obesity (VA≥100 cm2). 2) VA was positively correlated with each anthropometric variable, of which WC showed the highest correlation (r=0.73-0.77, P<0.001). 3) The best cut-off points for assessing abdominal visceral obesity were as followed: BMI of 26 kg/m2, WC of 90 cm, and WHR of 0.93, with WC being the most sensitive and specific factor. 4) Among subjects with BMI≥28 kg/m2 or WC≥95 cm, 95% of men and 90% of women appeared to have abdominal visceral obesity. Conclusion Measurements of BMI, WC, and WHR can be used in the prediction of abdominal visceral obesity, of which WC was the one with better accuracy. 展开更多
关键词 Body mass index (BMI) Abdominal visceral fat Anthropometric parameters Receiver operating characteristic (ROC) curves
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Spatiotemporal variation of drought characteristics in the Huang- Huai-Hai Plain, China under the climate change scenario 被引量:6
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作者 LI Xiang-xiang JU Hui +3 位作者 Sarah Garré YAN Chang-rong William D.Batchelor LIU Qin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2017年第10期2308-2322,共15页
Understanding the potential drought characteristics under climate change is essential to reduce vulnerability and establish adaptation strategies, especially in the Huang-Huai-Hai Plain (3H Plain), which is a major ... Understanding the potential drought characteristics under climate change is essential to reduce vulnerability and establish adaptation strategies, especially in the Huang-Huai-Hai Plain (3H Plain), which is a major grain production area in China. In this paper, we investigated the variations in drought characteristics (drought event frequency, duration, severity, and intensity) for the past 50 years (1961-2010) and under future scenarios (2010-2099), based on the observed meteorological data and the Representative Concentration Pathway (RCP) 8.5 scenario, respectively. First, we compared the applicability of three climatic drought indices: the standardized precipitation index (SPI), the standardized precipitation evapotranspiration index based on the Penman-Monteith equation (SPEI-PM) and the same index based on the Thornthwaite equation (SPEI-TH) to correlate the recorded agricultural drought areas. Then, we analyzed the drought characteristics using 'run theory' for both historical and the future RCP 8.5 scenario based on the best performing index. Correlation analyses between drought indices and agricultural drought areas showed that SPEI-PM performed better than SPI and SPEI-TH in the 3H Plain. Based on the results of SPEI-PM, drought risks including duration, severity and intensity during 1961-2010 showed an decreasing trend. However, under the RCP 8.5 scenario, drought is expected to rise in frequency, duration, severity, and intensity from 2010-2099, although drought components during the 2010-2039 are predicted to be milder compared with historical conditions. This study highlights that the estimations for atmospheric evaporative demand would create differences in the prediction of long-term drought trends by different drought indices. The results of this study can help inform researchers and local policy makers to establish drought management strategies. 展开更多
关键词 climate change drought index drought characteristics Huang-Huai-Hai Plain
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DYNAMIC RESPONSE OF ROLLER GEAR INDEXING CAM SYSTEM CONSIDERING CLEARANCE AND MOTOR CHARACTERISTIC 被引量:4
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作者 Chang Zongyu Civil Aviation College,Nanjing University of Aeronautics and Astronautics Zhang Ce Yang Yuhu Wang Yuxin Tianjin University 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2001年第2期189-192,共4页
The dynamic responses of roller gear indexing cam mechanism are investigated .With applying Lagarange equation and Gear method,motion equations of this mechanism including clearance,motor characteristic,torsion flexib... The dynamic responses of roller gear indexing cam mechanism are investigated .With applying Lagarange equation and Gear method,motion equations of this mechanism including clearance,motor characteristic,torsion flexibility are developed and solved.The results show that clearance affects primarily the response on turret,and has little effects on the responses on rotary table.At the same time,the velocity fluctuation of motor shaft is not serious for the existence of inertia of reducer,and the high frequency of velocity fluctuation of camshaft is related with the torsion stiffness of shaft and the clearance between pairs. 展开更多
关键词 Roller gear indexing cam mechanism CLEARANCE Motor characteristic Dynamic response
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Remote Sensing Monitoring of Surface Characteristics in the Badain Jaran, Tengger, and Ulan Buh Deserts of China 被引量:2
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作者 LIU Qingsheng LIU Gaohuan +1 位作者 HUANG Chong LI He 《Chinese Geographical Science》 SCIE CSCD 2019年第1期151-165,共15页
Deserts and sandy land in northern China are very susceptible to sandy desertification and are the main source of sand-dust storms of Asian dust. However, because of the complex factors involved, descriptions of the r... Deserts and sandy land in northern China are very susceptible to sandy desertification and are the main source of sand-dust storms of Asian dust. However, because of the complex factors involved, descriptions of the relationship between sandy desertification and surface characteristics in these regions are lacking. We monitored the surface characteristics and their changes in time using information about soil, vegetation, and landforms in the Badain Jaran Desert(BJD), Tengger Desert(TD), and Ulan Buh Desert(UBD) in the northern China. The monitoring was done using tasseled cap angle(TCA), disturbance index(DI), and topsoil grain size index(TGSI) from Moderate Resolution Imaging Spectroradiometer(MODIS) images combined with a decision tree classification. Results showed that the TD had higher topsoil fine sand content, and the ratio of non-vegetated to vegetated areas was similar with that in the UBD. Northeast-southwest coarse sand dunes with thin interdune(NECTI) dominated the BD, fine sand dunes(FSD) dominated the TD, and a combination of northeast-southwest coarse sand dunes with wide interdune(NECWI) and northwest-southeast coarse sand dunes with wide interdune(NWCWI) dominated the UBD. From 2000 to 2015, in the BJD the area of the NECTI, non-sand dune(Non) and potential sand sources(PSS) increased, whereas the area of the NECWI, FSD and NWCWI decreased, indicating a improve process in the BJD. In the TD, the area covered by Non increased, whereas the area covered by PSS, NECWI, NECTI, FSD, and NWCWI decreased from 2000 to 2015. The area covered by the various surface characteristic types fluctuated annually in the UBD from 2000 to 2015. Changes in surface characteristics reflect the combined effects of natural conditions and human activity. The findings of our study will assist scientists and policy makers in proposing different management techniques to combat sandy desertification for the different surface characteristics of these regions. 展开更多
关键词 surface characteristics MODIS DESERT tasseled CAP angle DISTURBANCE index TOPSOIL GRAIN size index
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Relationship between Environmental Pollution of Coal Mine and Spectral Characteristics of Nearby Plants 被引量:3
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作者 Liqing Lei Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China 《Journal of University of Science and Technology Beijing》 CSCD 2001年第1期10-14,共5页
Remote sensing technology, as the most advanced method for collecting data, along with the common ways often used in the past on research of environmental science, was integrated to study the relationship between envi... Remote sensing technology, as the most advanced method for collecting data, along with the common ways often used in the past on research of environmental science, was integrated to study the relationship between environmental pollution of coal mine and spectral characteristics of nearby plants. With compositive index and mean reflectivity at near infrared, a regression equation was established, and a conclusion was made that spectral reflectivity can be used to distinguish regions with different pollution degree. Through testing with real status of the research region, it is verified that this kind of integration and conclusion not only are helpful for human being in controlling the movement law of pollutants and the corresponding change of coal mine environmental quality but also bring a new way for the research of environment problems of coal mine. 展开更多
关键词 remote sensing spectral characteristics REFLECTIVITY pollution index compositive index atmospheric pollution
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Urban Spatial Expansion Characteristics in China’s Rapid Urbanization Region—A Case Study of SXC Region 被引量:3
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作者 Min Qian Lijie Pu +1 位作者 Jing Zhang Meng Zhang 《International Journal of Geosciences》 2013年第10期1365-1375,共11页
Urban spatial expansion characteristics are the responses of urbanization acts on the geographical space. Analyzing the characteristics can reveal the process of urban expansion and mechanism which is one of useful me... Urban spatial expansion characteristics are the responses of urbanization acts on the geographical space. Analyzing the characteristics can reveal the process of urban expansion and mechanism which is one of useful methods to find out the sustainable land use strategy balancing development and protection. In this paper, two main methods have been deployed in analyzing the spatial expansion characteristics of rapid urbanization region. One is the expansion index method and the other is fractal dimension method. And the results show that town-level urban sprawl has increased in a non-linear way since 1985, and even the increments of the urban expansion intensity are fluctuated. Morphology transformation from scatter to concentration is common phenomenon in the process of urbanization in the towns. From the morphology point of view, downtowns are more homogenous than towns with less variation. The concentration is the leading development trend in downtowns. And the more distance from the downtown is, the more spatial pattern morphology will be observed. These characteristics indicate that macro-scale policies of economic development and land use management have great impacts on the formation and characteristics of spatial patterns of urban dynamic patterns. 展开更多
关键词 Spatial EXPANSION characteristics EXPANSION index FRACTAL Dimension Town-Level Rapid URBANIZATION REGION
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Time-Series Characteristics of Wind Power and Its Impact on Jilin Power Grid 被引量:2
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作者 Yanping Xu Yong Sun +3 位作者 Taiyi Zheng Hongyi Cai Peng Li Shuo Ma 《Journal of Power and Energy Engineering》 2014年第4期203-212,共10页
With the rapid development of wind power, the large-scale wind power integration brings a new range of issues in dispatching operation. In order to gain a better grasp of the influence caused by wind power combined to... With the rapid development of wind power, the large-scale wind power integration brings a new range of issues in dispatching operation. In order to gain a better grasp of the influence caused by wind power combined to the grid, the paper first establishes the impact characteristic indexes, and then analyzes the regularity of wind power time series in different spatial and temporal scales. At last, according to the analysis results, this paper assesses the impact of time-series characteristics of wind power on power grid, such as the frequency regulation, peak load regulation, which can provide the reference for wind power optimal dispatching of Jilin Power Grid. 展开更多
关键词 characteristIC index Time-Series characteristics Frequency REGULATION PEAK LOAD REGULATION
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ANALYSIS OF “BIMODAL PATTERN” STORM ACTIVITY CHARACTERISTICS OF THE BAY OF BENGAL 被引量:1
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作者 段旭 段玮 林志强 《Journal of Tropical Meteorology》 SCIE 2017年第2期191-201,共11页
Storms that occur at the Bay of Bengal(Bo B) are of a bimodal pattern, which is different from that of the other sea areas. By using the NCEP, SST and JTWC data, the causes of the bimodal pattern storm activity of the... Storms that occur at the Bay of Bengal(Bo B) are of a bimodal pattern, which is different from that of the other sea areas. By using the NCEP, SST and JTWC data, the causes of the bimodal pattern storm activity of the Bo B are diagnosed and analyzed in this paper. The result shows that the seasonal variation of general atmosphere circulation in East Asia has a regulating and controlling impact on the Bo B storm activity, and the "bimodal period" of the storm activity corresponds exactly to the seasonal conversion period of atmospheric circulation. The minor wind speed of shear spring and autumn contributed to the storm, which was a crucial factor for the generation and occurrence of the"bimodal pattern"storm activity in the Bo B. The analysis on sea surface temperature(SST) shows that the SSTs of all the year around in the Bo B area meet the conditions required for the generation of tropical cyclones(TCs). However,the SSTs in the central area of the bay are higher than that of the surrounding areas in spring and autumn, which facilitates the occurrence of a "two-peak"storm activity pattern. The genesis potential index(GPI) quantifies and reflects the environmental conditions for the generation of the Bo B storms. For GPI, the intense low-level vortex disturbance in the troposphere and high-humidity atmosphere are the sufficient conditions for storms, while large maximum wind velocity of the ground vortex radius and small vertical wind shear are the necessary conditions of storms. 展开更多
关键词 storm of BoB "bimodal pattern" activity characteristics cause analysis environmental conditions GPI index
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Effects of Copper-based Nutritional Foliar Fertilizers on Photosynthetic Characteristics,Yield and Disease Control Efficiency of Cotton 被引量:1
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作者 Qiang MA Wei WANG +5 位作者 Hongjie LI Xiangjun WANG Zishuang LI Tongkai ZHAO Xianhe ZHENG Yanxiao TAN 《Agricultural Biotechnology》 CAS 2019年第1期140-149,共10页
[Objectives] The effects of copper-based nutrient foliar fertilizer on photosynthetic characteristics,yield,accumulation and distribution of trace elements in various organs,disease prevention effect and soil enzyme a... [Objectives] The effects of copper-based nutrient foliar fertilizer on photosynthetic characteristics,yield,accumulation and distribution of trace elements in various organs,disease prevention effect and soil enzyme activity were studied,so as to provide a theoretical basis for the application of foliar fertilizers in cotton production. [Methods]Through two years of field experiments,six treatments were set in total,namely spraying water( CK),traditional Bordeaux mixture( BDM),Kocide 2000( KCD),copper-based nutrient foliar fertilizer( CF),iron-copper-based nutrient foliar fertilizer( CFFe),and zinc-boron-copper-based nutrient foliar fertilizer( CFZnB). Randomized block arrangement was adopted. Chlorophyll content in leaves was measured at each growth stage of the cotton. Photosynthetic characteristics of leaves were measured at the peak bolling stage. Plants were sampled at initial boll opening stage. The whole plant was divided into root,stem,leaf and cotton boll parts,in which the total copper,total zinc,total iron contents and accumulations were determined. Soil samples were collected from each plot,followed by the determination of soil enzyme activity. Disease index was investigated at bud,flowering and boll-forming and boll opening stage. [Results]( 1) Spraying CFFe,CFZnB,CF and KCD could significantly improve chlorophyll content of cotton leaves,and the CFFe treatment had the highest increase up to13. 30%,followed by the CFZnB treatment,which was 11. 40% higher than the CK; and photosynthetic rate,stomata conductance and transpiration rate could be improved significantly,and the CFFe treatment showed the highest photosynthetic rate,which increased by 26. 35% compared with the CK,followed by the CFZnB treatment,which increased by 17. 96% compared with CK; and intercellular CO2 concentration was significantly reduced.( 2) Spraying BDM,KCD,CF,CFFe and CFZnB can significantly increase total copper content and accumulation in various cotton organs( except the total copper content in the stem part of the CFZnB treatment; the CFZnB and CFFe treatments can significantly increase total zinc content and accumulation in various cotton organs; and spraying CFFe,CFZnB and CF can significantly increase total iron content and accumulation in various cotton organs( except the total iron content in the stem part of the CF treatment).( 3)Spraying CFFe,CFZnB,CF,KCD and BDM greatly reduced the disease index at flowering and boll-forming and boll opening stages.( 4) The CFZnB and CFFe treatments had the highest soil urease activity,which was 7. 14% higher than that of the CK,but the difference from the CK was not significant; the catalase activity of each treatment was significantly higher than that of the BDM treatment; and the sucrase activity of each treatment was significantly higher than that of the CK.( 5) Spraying CFFe,CFZnB,CF and KCD significantly improved lint yield of cotton,and the CFZnB treatment showed the highest yield increase up to 12. 34%,followed by the CFFe treatment,with an increase in the range of 8. 77%-10. 20%. [Conclusions]Copper-based nutrient foliar fertilizers have dual functions of disease control and prevention and plant nutrition and health care,and not only can significantly increase cotton yield,but also has certain disease prevention effect.It is recommended to use copper-based nutrient foliar fertilizers. 展开更多
关键词 COPPER-BASED nutrient FOLIAR fertilizer COTTON PHOTOSYNTHETIC characteristics YIELD Disease index Trace elements Soil enzyme activity
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Acidolysis hydrocarbon characteristics and significance of sediment samples from the ODP drilling legs of gas hydrate 被引量:1
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作者 Xun Sun Chunyan Sun +3 位作者 Jiangyun Xiang Jihui Jia Panfeng Li Zhibin Zhang 《Geoscience Frontiers》 SCIE CAS 2012年第4期515-521,共7页
To study on the significance and basis of acidolysis index to China marine gas hydrate exploring, since 2006, 111 samples derived from Leg 164 and 204 of the Ocean Drilling Program (ODP) were analyzed in the experim... To study on the significance and basis of acidolysis index to China marine gas hydrate exploring, since 2006, 111 samples derived from Leg 164 and 204 of the Ocean Drilling Program (ODP) were analyzed in the experiment center of China Petroleum Exploration Research Institute to obtain data on acidolysis hydrocarbon index and methane carbon isotopes by the gas chromatography (GC) of PE AutoSystem XL and isotope mass spectrometer (IRMS) of Finnigan MAT25 I. Through these, we study the reliability of the acidolysis method and characterize the gas hydrate potential. The results show that the acidolysis hydrocarbon index has a stable correspondence with the Gas Hydrate Stability Zone (GHSZ) in the ODE and that there are clear abnormal signs in shallow samples that might reliably reflect the existence of authigenic carbonate caused by hydrocarbon migration from bottom hydrate. We therefore propose that the ability to characterize the acidolysis hydrocarbon is crucial to submarine gas hydrate exploration in China. 展开更多
关键词 Ocean Drilling Program (ODP) Gas Hydrate Stability Zone (OHSZ) Acidolysis hydrocarbon index Acidolysis hydrocarbon methane carbon isotopes Geochemical characteristics
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Evaluation Indices of Interaction Ability of Asphalt and Aggregate Based on Rheological Characteristics 被引量:2
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作者 谭忆秋 李晓琳 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2012年第5期979-985,共7页
In order to find a parameter as the evaluation index that can capture the effect of the interaction between asphalt and aggregate, the rheological properties of asphalt mastics using two kinds of asphalts and four kin... In order to find a parameter as the evaluation index that can capture the effect of the interaction between asphalt and aggregate, the rheological properties of asphalt mastics using two kinds of asphalts and four kinds of aggregates under different filler-asphalt ratios were measured by a dynamic shear rheometer (DSR). Moreover, four rheological parameters of K.Ziegel-B, Luis Ibrarra-A, complex shear modulus ΔG*and complex viscosity Δη* for evaluating the interaction ability were studied. Results indicate that all the four parameters can characterize the interaction ability of asphalt and aggregate correctly and feasibly. Through the comparison of sensitivities and physical meanings of the four parameters, K.Ziegel-B with high sensitivity and exact physical meaning is finally selected as the evaluation index for interaction ability of asphalt and aggregate. 展开更多
关键词 asphalt mastic interface interactions evaluation index rheological characteristic
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