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Analysis on Variation of Rainfall Trend and Agriculture Dryness in Benxi City of Liaoning Province 被引量:4
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作者 李志静 李西平 《Meteorological and Environmental Research》 CAS 2010年第7期82-85,共4页
Linear regression,climate trend rate,integral humidity indicator and dry-wet index were adopted to analyze the precipitation change,drought or waterlogging frequency and occurrence period in Benxi of Liaoning.The resu... Linear regression,climate trend rate,integral humidity indicator and dry-wet index were adopted to analyze the precipitation change,drought or waterlogging frequency and occurrence period in Benxi of Liaoning.The results showed that in recent 55 years,the tendency rate of annual precipitation in Benxi was-30.749 mm/10 a,reducing 165 mm in trend;the precipitation tendency rate during the growing season of plants was-31.371/10 a,reducing 173 mm in trend.The climate type was changed from light flood 20 a ago to wet type.The satisfaction of agriculture-required water was above 150% and annual average precipitation surplus was 290 mm.Benxi was hit by the medium floods to heavy floods in 10 years,about once in five years.The occurrence period of mild drought was 5 a,about once in ten years.The drought in spring below the medium degree occurred twice in a decade while the waterlogging above the medium degree occurred once in a decade.The waterlogging in summer above the medium degree occurred once in two years.The waterlogging in autumn above the medium degree occurred twice in a decade while the drought below the medium degree occurred four times in a decade.The occurrence frequency of heavy waterlogging in July and August was 54.5%.May and September were the period of time with a strikingly higher prevalence in drought. 展开更多
关键词 PRECIPITATION Variation trend dryness AGRICULTURE Benxi China
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Radiative dryness index and potential productivity of vegetation in China 被引量:2
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作者 Zhang Xinshi (Chang Hsin-shih) and Yang DiananInstitute of Botany,Chinese Academy of Sciences,Beijing 100044,China 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1990年第4期95-109,共15页
The Chikugo Model is used to estimate radiative dryness indexes (RDI) and net primary productivity (NPP) of vegetation zones in China by calculating cli-matic parameters. That provides the water-heat equilibrium condi... The Chikugo Model is used to estimate radiative dryness indexes (RDI) and net primary productivity (NPP) of vegetation zones in China by calculating cli-matic parameters. That provides the water-heat equilibrium condition, potential primary production for natural vegetation in various vegetation zones, and their geographical distribution pattern. That could be used as the basis for study the effect of global climate change on ecosystems. 展开更多
关键词 Chikugo Model radiative dryness index net primary productivity.
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Dynamic Drought Monitoring in Guangxi Using Revised Temperature Vegetation Dryness Index 被引量:4
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作者 LU Yuan TAO Heping WU Hua 《Wuhan University Journal of Natural Sciences》 CAS 2007年第4期663-668,共6页
Moderate resolution imaging spectroradiometer (MODIS) data are very suitable for vast extent, long term and dynamic drought monitoring for its high temporal resolution, high spectral resolution and moderate spatial ... Moderate resolution imaging spectroradiometer (MODIS) data are very suitable for vast extent, long term and dynamic drought monitoring for its high temporal resolution, high spectral resolution and moderate spatial resolution. The composite Enhanced Vegetation Index (EVI) and composite land surface temperature (Ts) obtained from MODIS data MOD11A2 and MOD13A2 were used to construct the EVI-Ts space. And Temperature Vegetation Dryness Index (TVDI) was calculated to evaluate the agriculture drought in Guangxi province, China in October of 2006. The results showed that the drought area in Guangxi was evidently increasing and continuously deteriorating from the middle of September to the middle of November. The TVDI, coming from the EVI-Ts space, could effectively indicate the spatial distribution and temporal evolution of drought, so that it could provide a strong technical support for the forecasting agricultural drought in south China. 展开更多
关键词 moderate resolution imaging spectroradiometer (MODIS) enhanced vegetation index land surface temperature temperature vegetation dryness index
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A Modified Temperature-Vegetation Dryness Index(MTVDI)for Assessment of Surface Soil Moisture Based on MODIS Data 被引量:1
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作者 WANG Hao LI Zongshan +2 位作者 ZHANG Weijuan YE Xin LIU Xianfeng 《Chinese Geographical Science》 SCIE CSCD 2022年第4期592-605,共14页
Spatio-temporal dynamic monitoring of soil moisture is highly important to management of agricultural and vegetation eco-systems.The temperature-vegetation dryness index based on the triangle or trapezoid method has b... Spatio-temporal dynamic monitoring of soil moisture is highly important to management of agricultural and vegetation eco-systems.The temperature-vegetation dryness index based on the triangle or trapezoid method has been used widely in previous studies.However,most existing studies simply used linear regression to construct empirical models to fit the edges of the feature space.This requires extensive data from a vast study area,and may lead to subjective results.In this study,a Modified Temperature-Vegetation Dryness Index(MTVDI)was used to monitor surface soil moisture status using MODIS(Moderate-resolution Imaging Spectroradiometer)remote sensing data,in which the dry edge conditions were determined at the pixel scale based on surface energy balance.The MTVDI was validated by field measurements at 30 sites for 10 d and compared with the Temperature-Vegetation Dryness Index(TVDI).The results showed that the R^(2) for MTVDI and soil moisture obviously improved(0.45 for TVDI,0.69 for MTVDI).As for spatial changes,MTVDI can also better reflect the actual soil moisture condition than TVDI.As a result,MTVDI can be considered an effective method to monitor the spatio-temporal changes in surface soil moisture on a regional scale. 展开更多
关键词 surface soil moisture Temperature-Vegetation dryness Index(TVDI) vegetation index MODIS Modified Temperature-Vegetation dryness Index(MTVDI)
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FEATURES OF DRYNESS AND WETNESS IN GUANGDONG PROVINCEOVER THE PAST FOUR DECADES
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作者 贺海晏 《Journal of Tropical Meteorology》 SCIE 1999年第1期33-42,共10页
Precipitation data from 86 observing Stations for the past four decades (from the first operational use to 1994) are used to study and discuss the character of annually mean distribution in Guangdong. Grades of drynes... Precipitation data from 86 observing Stations for the past four decades (from the first operational use to 1994) are used to study and discuss the character of annually mean distribution in Guangdong. Grades of dryness and wetness on a year-to-year basis are determined and preliminary features of dryness and wetness are discussed for the whole of the province and individual regions according to a 5-grade standard of division. The result has shown that there is on an average a rainfall of 1748 mm per year across the province, with four major centers of maxima (of annual rainfall over 2000 mm) at Enping, Qingyuan, Haifeng and Longmen. For the mean across the province, the years 1959. 1 961. 1973.1975, 1991 are anomalously wet and the years 1956, 1963, 1977 and 1991 are anomalously dry. of them, 1973 is the unusually wet year (with the absolute value of precipitation anomaly over twice as large as the standard deviation) and 1956 and 1963 are the usual dry years. For the occurrence frequency of unusually wetness and dryness over individual river valleys in the province, there are more years of dryness in the valleys of the Xijiang and Dongjiang Rivers. More years of wetness in that of the Jianjiang River, and only years of wetness instead of years of dryness in the valleys of Beijiang and Hanjiang Rivers. 展开更多
关键词 GUANGDONG PRECIPITATION dryness and wetness
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EVOLUTION LAW OF DRYNESS AND WETNESS IN KUNMING IN RECENT 300 YEARS
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作者 严华生 谢应齐 +3 位作者 赵筱青 曹杰 周传喜 罗兰仙 《Journal of Tropical Meteorology》 SCIE 1998年第2期208-214,共7页
Using indexes of dryness and wetness in historical record over the recent recent years and rainfall data over the tatest century, the work involves itself with the study of climatological evolution of dryness and wetn... Using indexes of dryness and wetness in historical record over the recent recent years and rainfall data over the tatest century, the work involves itself with the study of climatological evolution of dryness and wetness. periodic variations of climate and interannual laws of variation. The discussion also covers the subjects of effects of El Nino. sunspot, predictors of general circulation on climatic variation of dryness and wetness. There arc main conclusions as follows: (1) The main cyclic variations of climate are 40 and 11 years in Kunming. the former being subject to that of El Nino and the latter to that of sunspots. They are two principal factors for periodic variations of dryness and wetness in Kunming. (2) A close relationship exists between interannual variations and general circulation factors for Kunming. The comprehensive influence as imposed by ENSO and allocations of W.C.E. patterns of circulation in the westerly are ma.tor weather and climate causes for the interannual variations of precipitation in Kunming. 展开更多
关键词 DISASTERS by dryness and wetness CLIMATIC variation FACTORS of influence
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Serum 17β-estradiol and oral dryness feeling in menopause
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作者 Farzaneh Agha-Hosseini Iraj Mirzaii-Dizgah 《Health》 2011年第5期258-262,共5页
The aim of this study was to compare serum 17β-estradiol of menopausal women with/without Oral Dryness (OD) feeling, and evaluate the re-lationship between serum 17β-estradiol and severity of OD feeling. A case-cont... The aim of this study was to compare serum 17β-estradiol of menopausal women with/without Oral Dryness (OD) feeling, and evaluate the re-lationship between serum 17β-estradiol and severity of OD feeling. A case-control study was carried out on 70 selected menopausal women aged 40 - 77 years with or without OD feeling (35 as case, 35 as control) conducted at the Clinic of Oral Medicine, Tehran University of Medical Sciences. Xerostomia inventory (XI) score was used as an index of OD feeling severity. The serum 17β-estradiol concentration was measured by an enzyme immunoassay kit (ELISA). Statistical analysis of Student’s t-test and Spearman correlation coefficient was used. The mean serum concentration of 17β-estradiol was significantly lower in case than control. There was a significant negative correlation between XI score and concentration of 17β-estradiol in menopausal women (r = –0.311, P = 0.004). It seems that there is a negatively slight correlation between OD feeling severity and serum 17β-estradiol in menopausal women. 展开更多
关键词 MENOPAUSE ORAL dryness FEELING 17Β-ESTRADIOL SERUM
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Molecular Cloning and Sequence Analysis of a Tonoplast Aquaporin Gene TIP1 Associated with Tapping Panel Dryness in Hevea brasiliensis
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作者 Zhi ZOU Danhua WANG +2 位作者 Yeyong MO Feng AN Lifu YANG 《Agricultural Biotechnology》 CAS 2014年第3期14-17,共4页
[Objective]To address the role of aquaporins(AQPs)in the occurrence of Tapping Panel Dryness(TPD),a phenomenon with tapping incision blocked partly or entirely during latex exploiting in the rubber tree(Hevea bra... [Objective]To address the role of aquaporins(AQPs)in the occurrence of Tapping Panel Dryness(TPD),a phenomenon with tapping incision blocked partly or entirely during latex exploiting in the rubber tree(Hevea brasiliensis)that causes great losses on rubber production,a tonoplast aquaporin gene associated with TPD occurence was cloned and analyzed.[Method]Based on an EST down-regulated in TPD-affected rubber trees,a 774 bp cDNA designated HbTIP1 was isolated from the bark tissue of Hevea brasiliensis with a combination of in silico cloning and RT-PCR.And the gene structure and sequence characteristics were analyzed using bioinformatics tools.[Result]The cDNA includes a 759 bp ORF,8 bp 5’UTR and 7 bp 3’UTR.Sequence analysis indicated that HbTIP1putatively encodes 252 amino acids with a theoretical molecular weight(Mw)of 25.88 kDa and isolectric point(pI)of 4.96.Bioinformatics analysis suggested that the deduced protein is predicted to have six transmembrane helices located to the vacuolar membrane and to harbor one conserved MIP domain that can be grouped into the tonoplast intrinsic proteins(TIPs)of aquaporin family.Homology search revealed that the protein shares a similarity of more than 90%with the homologues in Theobroma cacao,Prunus persica,Citrus sinensis and Ricinus communis,supporting a highly conserved evolution.[Conclusion]This study provided basis for further revealing the regulatory role of AQPs in the TPD occurrence. 展开更多
关键词 Hevea brasiliensis Tapping panel dryness AQUAPORIN
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Perceived Efficacy of Vaginal Dryness Relief: A Comparative Clinical Study between <i>Sodium hyaluronate vaginal gel</i><sup>1</sup><i>vs. Promestriene cream</i><sup>2</sup>
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作者 Eduardo de Oliveira Duque-Estrada Vivian Pessoto Rosa +1 位作者 Mariane Martins Mosca Heliara Lopes do Nascimento 《Advances in Sexual Medicine》 2017年第1期34-43,共10页
In the study, we report the comparative efficacy of the sodium hyaluronate gel vaginal application and promestriene cream which were tested to treat the gynecological symptoms of people who suffered from vaginal dryne... In the study, we report the comparative efficacy of the sodium hyaluronate gel vaginal application and promestriene cream which were tested to treat the gynecological symptoms of people who suffered from vaginal dryness. Method: 35 patients applied sodium hyaluronate vaginal gel one time a day for a period of two times a week during three weeks and other 33 patients using promestriene cream applied it every day for a period of three weeks also. Results: No significant difference was observed between vaginal application of sodium hyaluronate gel and promestriene cream, regarding both, as regarding the dryness of the intimate mucosa (p = 0.786), the attribute of moisturizing properties to the intimate mucosa (p = 0.142), the comfort sensation (p = 0.528), and no significant difference was observed regarding the fragrance of the product (p = 0.088). Conclusion: The similar results between vaginal application of both products support the use of sodium hyaluronate vaginal gel (Lubrinat&reg;) in the initial approach of symptoms of vaginal dryness. 展开更多
关键词 VAGINAL dryness MENOPAUSE Sodium HYALURONATE Promestriene
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Retrieving Soil Moisture in Hebei by Using Temperature Vegetation Dryness Index
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作者 Fei Mao Lei Han 《Journal of Geoscience and Environment Protection》 2017年第8期10-16,共7页
The temperature-vegetation index space coupled with information of surface temperature and vegetation, is an important method to realize soil moisture estimation and agricultural drought monitoring. In order to estima... The temperature-vegetation index space coupled with information of surface temperature and vegetation, is an important method to realize soil moisture estimation and agricultural drought monitoring. In order to estimate the soil moisture in the study area, we collected soil relative humidity of Agricultural meteorological station and downloaded Moderate Resolution Imaging Spectrometer (MODIS) image data. Then, the temperature vegetation dryness index was calculated based on the MODIS Normalized difference vegetation index (NDVI) and land surface temperature (LST). A correlation analysis of TVDI and soil relative humidity at depth of 10 cm was carried out and an empirical model of moisture estimation was established. Finally, another set of data was used to validate the accuracy of model. The results show that the TVDI method can be used to achieve the soil moisture in the study area. The empirical model has certain universality in the study area, and obtains a high accuracy of soil moisture estimation with an R2 of 0.374 and RMSE of 11.73%. 展开更多
关键词 Remote Sensing INVERSION TEMPERATURE VEGETATION dryness INDEX
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Molecular Cloning and Sequence Analysis of an Aquaporin Gene Related to Tapping Panel Dryness in Rubber Tree( Hevea brasiliensis Muell. Arg. )
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作者 Zhi ZOU Yeyong MO +2 位作者 Dahua WANG Feng AN Lifu YANG 《Agricultural Biotechnology》 CAS 2014年第2期37-39,43,共4页
As a syndrome with tapping incision blocked partly or entirely during latex exploiting in rubber tree (Hevea brasiliensis ), "Tapping panel dryness (TPD)" causes great yield losses, thereby becoming the most imp... As a syndrome with tapping incision blocked partly or entirely during latex exploiting in rubber tree (Hevea brasiliensis ), "Tapping panel dryness (TPD)" causes great yield losses, thereby becoming the most important factor limiting rubber production. On the basis of an EST down-regulated in TPD-affected rubber trees, a 903 bp cDNA denoted HbPIP2;2 was isolated from the bark tissue with a combination of in silico cloning and RT-PCR. The cDNA contains an 867 hp ORF, 13 bp 5'UTR and 23 bp 3' UTR. Sequence analysis indicated that HbPIP2;2 encodes 288 amino acids with a theoretical molecular weight (Mw) of 30. 71 kDa and isolectric point (Pi) of 8.20. Bioinformatics analysis suggested that the deduced protein is predicted to have six transmembrane helices located to the plasma membrane and harbor one conserved MIP domain that can be grouped into plasma membrane intrinsic proteins (PIPs) of aquaporin (AQP) family. Homolo- gy search revealed that the protein shares a similarity of more than 90% with the homologues in Ricinus communis, Popttlus trichocarpa, Juglans regia and Theobro- ma cacao, suooorting a hie.hly conserved evolution. This study provided basis for further uncovering the regulatory role of AOPs in TPD occurrence. 展开更多
关键词 Hevea brasiliensis Tapping panel dryness AQUAPORIN Plasma membrane intrinsic protein
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Biome <i>Q<sub>10</sub></i>and Dryness
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作者 Chuixiang Yi Daniel Ricciuto George Hendrey 《American Journal of Climate Change》 2013年第4期292-295,共4页
Temperature sensitivity of soil respiration (Q10) is a critical parameter in carbon cycle models with important implications for climate-carbon feedbacks in the 21st century. The common assumption of a constant Q10, u... Temperature sensitivity of soil respiration (Q10) is a critical parameter in carbon cycle models with important implications for climate-carbon feedbacks in the 21st century. The common assumption of a constant Q10, usually with a value of 2.0, was shown to be invalid by a previous model-data fusion study that reported biome-specific values of this parameter. We extend the previous analysis by demonstrating that these biome-level values of Q10 also are a function of dryness (R2 = 0.54). When tundra and cultivated lands are excluded, the correlation is much stronger (R2 = 0.92). Therefore dryness is the primary driver for variability in respiration-temperature sensitivity in forest and grassland ecosystems. This finding has important implications for the response of the terrestrial carbon cycle to climate change, as it implies that the increasing dryness would potentially accelerate the respiration temperature sensitivity feedback. 展开更多
关键词 Climate Change Carbon Cycle Soil RESPIRATION dryness
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An improved temperature vegetation dryness index(iTVDI) and its applicability to drought monitoring 被引量:3
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作者 YANG Ruo-wen WANG Hai +2 位作者 HU Jin-ming CAO Jie YANG Yu 《Journal of Mountain Science》 SCIE CSCD 2017年第11期2284-2294,共11页
Using Moderate Resolution Imaging Spectroradiometer(MODIS) data from the dry season during 2010–2012 over the whole Yunnan Province, an improved temperature vegetation dryness index(iTVDI), in which a parabolic dry-e... Using Moderate Resolution Imaging Spectroradiometer(MODIS) data from the dry season during 2010–2012 over the whole Yunnan Province, an improved temperature vegetation dryness index(iTVDI), in which a parabolic dry-edge equation replaces the traditional linear dry-edge equation, was developed, to reveal the regional drought regime in the dry season. After calculating the correlation coefficient, root-mean-square error, and standard deviation between the iTVDI and observed topsoil moisture at 10 and 20 cm for seven sites, the effectiveness of the new index in depicting topsoil moisture conditions was verified. The drought area indicated by iTVDI mapping was then compared with the drought-affected area reported by the local government. The results indicated that the iTVDI can monitor drought more accurately than the traditional TVDI during the dry season in Yunnan Province. Using iTVDI facilitates drought warning and irrigation scheduling, and the expectation is that this new index can be broadly applied in other areas. 展开更多
关键词 IMPROVED TEMPERATURE vegetationdryness INDEX (iTVDI) Drought monitoring Lineardry-edge EQUATION Parabolic dry-edge EQUATION Soilmoisture
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Observed dryness and wetness variability in Shanghai during 1873-2005
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作者 张增信 张强 +2 位作者 张金池 邹兰军 江剑民 《Journal of Geographical Sciences》 SCIE CSCD 2009年第2期143-152,共10页
Dryness and wetness variations on different time scales in Shanghai were analyzed using the Standardized Precipitation Index (SPI) based on monthly precipitation data for 1873-2005. The SPI on scales of 3, 6, 12 and... Dryness and wetness variations on different time scales in Shanghai were analyzed using the Standardized Precipitation Index (SPI) based on monthly precipitation data for 1873-2005. The SPI on scales of 3, 6, 12 and 24 months has been calculated. The SPI on 3, 6, 12 and 24 months present 4 wet periods prevailed during 1873-1885, 1904-1923, 1938-1960 and 1983-2005, and 3 dry episodes during 1886-1903, 1924-1937 and 1961-1982. Significant periods of higher wavelet power in the SPI-24 months occurred on the time scales of 2-7-year band in around 1880-1890, 1910-1950 and 1970-1990, and at 8-15-year band in 1920-1960 and 1965-2000 respectively. Periodicities in the SOl and ENSO indices are similar to those in SPI-24 months with little difference, namely, in the SPI-24 months, there are significant periods at the 2-7- and 8-15-year bands during 1930-1940. The periodicity components in individual SPI-24 months, SOl and ENSO indices are more complicated, showing the wetness and dryness variability in Shanghai is controlled by more than one physical factors. The research results indicate that the Shanghai area has experienced dryness and wetness variability on different time scales during the past 133 years. 展开更多
关键词 dryness and wetness SPI continuous wavelet transform SHANGHAI
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The Coupled Effects of Dryness and Non-condensable Gas Content of Geothermal Fluid on the Power Generation Potential of an Enhanced Geothermal System
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作者 LI Tailu LI Xuelong +1 位作者 JIA Yanan GAO Xiang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2021年第6期1948-1957,共10页
The Enhanced Geothermal System(EGS) is a recognized geothermal exploitation system for hot dry rock(HDR), which is a rich resource in China. In this study, a numerical simulation method is used to study the effects of... The Enhanced Geothermal System(EGS) is a recognized geothermal exploitation system for hot dry rock(HDR), which is a rich resource in China. In this study, a numerical simulation method is used to study the effects of geothermal fluid dryness and non-condensable gas content on the specific enthalpy of geothermal fluid. Combined with the organic Rankine cycle(ORC), a numerical model is established to ascertain the difference in power generation caused by geothermal fluid dryness and non-condensable gas content. The results show that the specific enthalpy of geothermal fluid increases with the increase of geothermal fluid temperature and geothermal fluid dryness. If the dryness of geothermal fluid is ignored, the estimation error will be large for geothermal fluid enthalpy. Ignoring non condensable gas will increase the estimation of geothermal fluid enthalpy, so the existence of the non-condensable gas tends to reduce the installed capacity of a geothermal power plant. Additionally, both mass flow of the working medium and net power output of the ORC power generation system are increased with increasing dryness of geothermal fluid, however there is some impact of geothermal fluid dryness on thermal efficiency. 展开更多
关键词 hot dry rock geothermal fluid dryness non-condensable gas organic Rankine cycle
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Clinical Study on Application of Xinrun Tongluo Method Based on the Theory of Collateral Diseases in Treating Androgenic Baldness of Blood Heat Wind Dryness Syndrome
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作者 Yuanjie XU Guoqiang LIANG 《Agricultural Biotechnology》 CAS 2023年第5期104-107,共4页
[Objectives]To explore the intervention effect of the representative formula of Xinrun Tongluo method,Liangxue Xiaofeng Powder,on the incidence of androgenic alopecia in the syndrome of blood heat and wind dryness.[Me... [Objectives]To explore the intervention effect of the representative formula of Xinrun Tongluo method,Liangxue Xiaofeng Powder,on the incidence of androgenic alopecia in the syndrome of blood heat and wind dryness.[Methods]A total of 72 patients with androgenic alopecia in Suzhou TCM Hospital Affiliated to Nanjing University of Chinese Medicine from October,2022 to June,2023 were randomly divided into a control group(36 cases,treated with Western medicine)and a treatment group(36 cases,treated with Chinese herbal formula+Western medicine).The short-term and long-term efficacy of the two groups of patients was compared.[Results]The hair microscopic signs and short-term and long-term efficacy of the treatment group were significantly better than those of the control group before and after treatment,with a statistically significant difference(P<0.05).[Conclusions]The representative formula of Xinrun Tongluo method is Liangxue Xiaofeng Powder,which has better clinical efficacy as an auxiliary Western medicine in the treatment of androgenic alopecia patients with blood heat and wind dryness syndrome,and is worthy of further promotion and application in clinical practice. 展开更多
关键词 Xinrun Tongluo METHOD Androgenic ALOPECIA Syndrome of blood heat and WIND dryness
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基于气化理论探讨阳明燥金之内涵及临床应用
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作者 丛紫东 李晓凤 +4 位作者 都芮 宋博涵 梁嘉钰 苏宇情 杜武勋 《天津中医药大学学报》 CAS 2024年第10期870-875,共6页
基于气化理论从阳明燥金之性、用、常与变的角度探讨阳明燥金在自然、人体气化中的内涵,阐释如何利用药物气化调节阳明燥金之变。自然气化之阳明燥金揭示了气的收降之势,其性"清凉",其用为收敛肃降,阳明燥金当以气的阖、聚、... 基于气化理论从阳明燥金之性、用、常与变的角度探讨阳明燥金在自然、人体气化中的内涵,阐释如何利用药物气化调节阳明燥金之变。自然气化之阳明燥金揭示了气的收降之势,其性"清凉",其用为收敛肃降,阳明燥金当以气的阖、聚、收、降为顺。阳明燥金在自然气化过程中寓有敛阳入阴、气机右旋、阖降内收的气化趋势。人体气化之阳明燥金对应于肺、胃、大肠,与脾密切相关,司人身气机降敛,与中土、肝木共同维持气机升降。阳明燥金之变以热盛、气逆、积滞为主。以药物气化纠正阳明燥金之变当以斡旋中气、敛降肺金、达肝平木为治疗原则,选用顺应阳明燥金之性、用的药物。 展开更多
关键词 阳明燥金 气化理论 燥邪 收敛肃降
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基于温度植被干旱指数(TVDI)的甘肃省农业干旱监测方法研究
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作者 沙莎 王丽娟 +2 位作者 王小平 胡蝶 张良 《干旱气象》 2024年第1期27-38,共12页
改进温度植被干旱指数(Temperature Vegetation Dryness Index,TVDI)并明确TVDI的农业干旱等级阈值,对提高TVDI指数监测农业干旱能力有重要意义。利用近19 a的MODIS(Moderate Resolu⁃tion Imaging Spectro-radiometer,MODIS)遥感数据,... 改进温度植被干旱指数(Temperature Vegetation Dryness Index,TVDI)并明确TVDI的农业干旱等级阈值,对提高TVDI指数监测农业干旱能力有重要意义。利用近19 a的MODIS(Moderate Resolu⁃tion Imaging Spectro-radiometer,MODIS)遥感数据,基于单时次和多时次方法构建NDVI(Normalized Difference Vegetation Index,NDVI)-LST(Land Surface Temperature,LST)、EVI(Enhanced Vegetation In⁃dex,EVI)-LST、RVI(Ratio Vegetation Index,RVI)-LST、SAVI(Soil-Adjusted Vegetation Index,SAVI)-LST等几种特征空间,讨论TVDI计算方法,分析TVDI在甘肃省农业干旱监测中的适用性,并明确甘肃省夏季TVDI农业干旱分级标准。结果表明:(1)基于多时次方法构建的SAVI-LST特征空间TVDI更适合甘肃省农业干旱监测,其对土壤相对湿度(Relative Soil Moisture,RSM)拟合的均方根误差(Root Mean Squared Error,RMSE)和平均绝对误差(Mean Absolute Error,MAE)比NDVI-LST特征空间TVDI对RSM拟合的RMSE和MAE下降1%~5%;(2)TVDI适用于夏季甘肃省半干旱区、半湿润区、湿润区等非干旱区浅层10、20 cm土壤深度的农业干旱监测,RMSE和MAE约15.6%和12.6%,拟合误差湿润区<半湿润区<半干旱区;(3)利用TVDI与RSM线性关系确定的TVDI农业干旱等级更有利于提高TVDI监测农业干旱的准确性。 展开更多
关键词 温度植被干旱指数 干旱监测 多时次方法 土壤相对湿度
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南水北调西线工程水源区和受水区降水变化及丰枯遭遇特征分析
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作者 王荣 杜孝忠 +5 位作者 巢清尘 赵珊珊 叶殿秀 李修仓 李莹 张梦然 《气候变化研究进展》 CSCD 北大核心 2024年第5期571-580,共10页
基于规划中的南水北调西线工程区域内274个国家气象站1961—2022年逐日降水资料,分析了西线工程水源区和受水区年和四季降水量的时空分布特征,以及两区降水的丰枯遭遇特征。结果表明:近62年来,南水北调西线工程水源区年降水量总体呈增... 基于规划中的南水北调西线工程区域内274个国家气象站1961—2022年逐日降水资料,分析了西线工程水源区和受水区年和四季降水量的时空分布特征,以及两区降水的丰枯遭遇特征。结果表明:近62年来,南水北调西线工程水源区年降水量总体呈增多趋势,而受水区年降水量没有明显变化趋势;夏、冬季水源区和受水区降水量均增多,春、秋季水源区降水量增多而受水区降水量减少;年和春、夏、秋季水源区枯水频率均低于受水区枯水频率,并且水源区枯水频率呈减少趋势,而丰水频率呈增加趋势;水源区和受水区年和四季降水丰枯异步频率普遍在60%以上,远大于丰枯同步频率,有利调水的5种丰枯遭遇在年和春、夏、秋季发生频率均超过50%。总体而言,南水北调西线工程水源区和受水区的降水具有较强的丰枯补偿性,且1971年以来有利调水发生频次呈增加趋势,理论上存在保证供水的可能性。但水源区出现连续枯水年的频次较多。因此,在南水北调西线工程规划设计和运行调度时需充分考虑水源区和受水区降水的变化。 展开更多
关键词 降水 丰枯遭遇 南水北调西线 水源区 受水区
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试论“知母坚阴护卫”
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作者 吴圣贤 石乃欣 王永炎 《吉林中医药》 2024年第10期1151-1157,共7页
知母为经典清热泻火药,其在苦寒之性泻火存阴的基础上能甘寒滋阴,具有直接的泻火坚阴之效。卫气出于下焦而实上焦,根源于肾,经肺充实布散。知母兼具清肺中实热、滋肾中阴液之效,在减少损耗的同时,能使卫气化生有源,故有顾护卫气之功效... 知母为经典清热泻火药,其在苦寒之性泻火存阴的基础上能甘寒滋阴,具有直接的泻火坚阴之效。卫气出于下焦而实上焦,根源于肾,经肺充实布散。知母兼具清肺中实热、滋肾中阴液之效,在减少损耗的同时,能使卫气化生有源,故有顾护卫气之功效。伏燥在内,耗伤肺肾阴津,致卫气化源不足、卫外失司,若遇外感引动,则相兼发病。其在体内有燥重为寒、化气为湿、复气为火的病机转化过程。知母在清热的同时兼滋养下焦之阴,能清润伏燥之时,充实卫气化生之源,发挥坚阴护卫之功,以有效截断伏燥外感病情的传变。这一独特应用价值在经典的中成药金花清感颗粒和银翘清热片中得到了充分体现。 展开更多
关键词 知母 坚阴护卫 伏燥
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