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Structural Features and Biological Activities of Bioactive Compounds from Fortunella margarita(Lour.) Swingle:A Review 被引量:2
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作者 曾红亮 陈培琳 +4 位作者 黄灿灿 沈瑾烨 常青 郑宝东 张怡 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2017年第12期2123-2132,共10页
Fortunella margarita(Lour.) Swingle, commonly known as kumquat, is the smallest citrus fruit. It thrives in southeastern China and is widely cultivated and consumed in the world due to its multiple health benefits. ... Fortunella margarita(Lour.) Swingle, commonly known as kumquat, is the smallest citrus fruit. It thrives in southeastern China and is widely cultivated and consumed in the world due to its multiple health benefits. It has been used as an important herbal medicine in traditional Chinese medicine and also as one of the most popular fruits. There are various kinds of bioactive compounds in F. margarita, such as polysaccharides, limonoids, essential oils, flavonoids, phenolic acids, vitamins, dietary fiber, etc. In addition, many studies have reported that these bioactive compounds can be used as antioxidant, antimicrobial, hypolipidemic, drosophila lure components in functional foods, pharmaceuticals and daily chemical products due to their biological activities. This review focuses on the structural features and biological activities of polysaccharides, limonoids, essential oils and flavonoids and other bioactive substances from F. margarita and their potential applications in food, daily chemical and pharmaceutical industries. 展开更多
关键词 FortuneUa margarita (Lour.) Swingle bioactive compounds structural features biological activities APPLICATION
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Recognition of Offline Handwritten Arabic Words Using a Few Structural Features
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作者 Abderrahmane Saidi Abdelmouneim Moulay Lakhdar Mohammed Beladgham 《Computers, Materials & Continua》 SCIE EI 2021年第3期2875-2889,共15页
Handwriting recognition is one of the most significant problems in pattern recognition,many studies have been proposed to improve this recognition of handwritten text for different languages.Yet,Fewer studies have bee... Handwriting recognition is one of the most significant problems in pattern recognition,many studies have been proposed to improve this recognition of handwritten text for different languages.Yet,Fewer studies have been done for the Arabic language and the processing of its texts remains a particularly distinctive problem due to the variability of writing styles and the nature of Arabic scripts compared to other scripts.The present paper suggests a feature extraction technique for offlineArabic handwriting recognition.A handwriting recognition system for Arabic words using a few important structural features and based on a Radial Basis Function(RBF)neural networks is proposed.The methods of feature extraction are central to achieve high recognition performance.The proposed methodology relies on a feature extraction technique based on many structural characteristics extracted from the word skeleton(subwords,diacritics,loops,ascenders,and descenders).In order to reach our purpose,we built our own word database and the proposed system has been successfully tested on a handwriting database of Algerian city names(wilayas).Finally,a simple classifier based on the radial basis function neural network is presented to recognize certain words to verify the reliability of the proposed feature extraction.The experiments on some images of the benchmark IFN/ENIT database show that the proposed system improves recognition and the results obtained are indicative of the efficiency of our technique. 展开更多
关键词 Offline Arabic handwriting recognition PREPROCESSING feature extraction structural features RBF neural network
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Morpho-structural Features and Structural Classification of Chromite Pods in the Tropoje-Has Ophiolite Massif, Albania
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作者 Ibrahim MILUSHI Nezir MEKSHIQI 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期234-,共1页
Tropoje-Has ophiolitic massif of eastern Mirdita(Albania)ophiolitic belt,is a major source for metallurgical chromite ore in Albania.Massif consists of a thick mantle section of SSZ type,8-10 km thick and
关键词 Morpho-structural features and structural Classification of Chromite Pods in the Tropoje-Has Ophiolite Massif Albania
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STRUCTURAL FEATURES OF THE MEIYU FRONT SYSTEM 被引量:6
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作者 高守亭 周玉淑 雷霆 《Acta meteorologica Sinica》 SCIE 2002年第2期195-204,共10页
A new subtropical front near the periphery of the West Pacific subtropical anticyclone is found,which is never revealed in previous studies.The coupling of the subtropical front and Meiyu front forms a Meiyu front sys... A new subtropical front near the periphery of the West Pacific subtropical anticyclone is found,which is never revealed in previous studies.The coupling of the subtropical front and Meiyu front forms a Meiyu front system (MFS) and is the most direct synoptic system for the Meiyu precipitation along the Mid-lower Reaches of Yangtze River (MRYR) in China.In this paper.The detailed structural features and cloud features of the MFS in 1998 and 1999 are analyzed,which manifests that the MFS is an objective phenomenon over the period of Meiyu along MRYR and the Southwest Japan.Generally.the subtropical front is mainly located between 850 hPa and 500 hPa.The moist southwest monsoon is transported in the passageway between the Meiyu front and the subtropical front.The vertical motion ascends in the passageway and descends on both sides of the MFS.forming the MFS's secondary circulation.A lower TBB band indicated that obvious convective activities are also located in the passageway of MFS.The horizontal wind of MFS is vertically asymmetric. 展开更多
关键词 Meiyu front subtropical front Meiyu front system(MFS) structural features
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Influences of tissue composition and structural features of biological media on the ultrasonic nonlinearity parameter 被引量:4
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作者 GONG Xiufen LIU Xiaozhou ZHANG Dong Rui Bing and CAO Lianzhi(Institute of Acoustics, Nanjing University, Nanjing 210008)Nanjing Meat Processing Plant. 《Chinese Journal of Acoustics》 1993年第3期265-270,共6页
The Acoustic nonlinearity parameter is an important parameter in nonlinear acoustics. In this article, the nonlinearity parameter B / A of normal and eight kinds of pathological porcine liver tissues were measured by ... The Acoustic nonlinearity parameter is an important parameter in nonlinear acoustics. In this article, the nonlinearity parameter B / A of normal and eight kinds of pathological porcine liver tissues were measured by finite amplitude insert-substitution method. The mixture law for nonlinearity parameter is used to analyze and predict the volume fractions of the components in a given tissue. It was found that the nonlinearity parameter is sensitive to the pathological forms of biological tissues and the values of B / A depend on the tissue composition and structural features. 展开更多
关键词 Tissue composition structural features Nonlinearity parameter.
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Creating burdock polysaccharide-oleanolic acid-ursolic acid nanoparticles to deliver enhanced anti-inflammatory effects:fabrication,structural characterization and property evaluation 被引量:3
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作者 Shanshan Zhu Zhichang Qiu +5 位作者 Xuguang Qiao Geoffrey I.N.Waterhouse Wenqing Zhu Wenting Zhao Qiuxia He Zhenjia Zheng 《Food Science and Human Wellness》 SCIE CSCD 2023年第2期454-466,共13页
This study explored the potential of polysaccharides from Actium lappa(ALPs)as natural wall materials for producing ALP-based nanoparticles to deliver poorly water-soluble oleanolic acid(OA)and ursolic acid(UA).Encaps... This study explored the potential of polysaccharides from Actium lappa(ALPs)as natural wall materials for producing ALP-based nanoparticles to deliver poorly water-soluble oleanolic acid(OA)and ursolic acid(UA).Encapsulating OA+UA with ALPs(ALP:OA+UA,50:1;OA:UA,1:1)changed the crystalline nature to a more amorphous state through hydrogen bonding and involving O-H/C-O/O-C-O groups.ALP-OA/UA nanoparticles had a particle size and zeta potential(in water)of 199.1 nm/-7.15 mV,with a narrow unimodal size distribution,and excellent pH,salt solution,temperature and storage stability.Compared with ALPs,ALPOA/UA nanoparticles showed enhanced anti-inflammatory activity(especially at a dose of 100μg/mL)in a CuSO-induced zebrafish inflammation model via down-regulating the NF-κB signalling pathway and gene expression of associated transcription factors and cytokines(TNF-α,IL-1βand IL-8).Therefore,ALP-based nanoparticles are natural and anti-inflammatory carriers for hydrophobic bioactive molecules. 展开更多
关键词 ENCAPSULATION structural features Particle size Zeta potential Thermodynamic properties In vivo verification
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Thermal treatment effect on structural features of mechano-synthesized fluorapatite-titania nanocomposite: A comparative study
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作者 Bahman NASIRI-TABRIZI 《Journal of Advanced Ceramics》 SCIE CAS 2014年第1期31-42,共12页
The influence of thermal treatment on the structural features of mechano-synthesized fluorapatite-titania composite nanopowders was studied.A mixture of calcium and phosphate reagents was mixed with a certain amount o... The influence of thermal treatment on the structural features of mechano-synthesized fluorapatite-titania composite nanopowders was studied.A mixture of calcium and phosphate reagents was mixed with a certain amount of titania(20 wt%)and then was mechanically activated for 5 h,10 h and 15 h respectively.After that,the mechano-synthesized powders were annealed at 700℃for 2 h.The crystallite size of the composite nanopowders estimated from Williamson-Hall method was in good agreement with transmission electron microscopy(TEM)analysis.Scanning electron microscopy(SEM)/TEM images confirmed the formation of a cluster-like composite which was composed of ellipse-like nanoparticles with an average size of about 16±7 nm after 15 h of milling.During the milling process,large variations in mechanochemical behavior of the CaHPO_(4)-Ca(OH)_(2)-CaF2-TiO_(2) system were detected.After the beginning of milling,no trace of the composite was found due to the lack of sufficient time for the mechanical activation.When the mechanical activation time increased to 15 h,composite nanopowders with the crystallite size of around 21.66 nm were formed.During heating at 700℃,the recovery of crystallinity occurred and the fraction of crystalline phase reached a maximum around 88.79%for the 10-h milled sample.Results indicated that the structural features of the composite were strongly influenced by the subsequent annealing. 展开更多
关键词 NANOCOMPOSITE FLUORAPATITE thermal treatment Williamson-Hall method structural features
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The relationship between the oil shale density and the structural features of corresponding kerogens
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作者 Qian Wang Congfei Yao +4 位作者 Yuanyuan Zhou Yuanjun Che Hongchen Liu Xiaosheng Zhao Yumeng Zhang 《Carbon Resources Conversion》 2022年第1期84-91,共8页
Based on the difference in the density and content of kerogen and inorganic minerals, oil shale can be separatedinto different density fractions. The structural features of kerogens in Beipiao oil shale (a kind of typ... Based on the difference in the density and content of kerogen and inorganic minerals, oil shale can be separatedinto different density fractions. The structural features of kerogens in Beipiao oil shale (a kind of typical lowgrade oil shale resources) with densities of 1.8–1.9, 1.9–2.0 and 2.0–2.1 g/cm3 were studied. Combined withour previous study on the structural features of Longkou and Huadian oil shales (two kinds of high-grade oil shaleresources) with different densities, the relationship between the oil shale density and the structural features ofcorresponding kerogens was revealed from aromatic, aliphatic structures and heteroatom species. The resultsshow that with increasing the density, the content of minerals increases, whereas that of kerogen decreases. Withincreasing the density, the aliphaticity, average methylene chain length and average number of attachments oneach aromatic ring increase. Whereas, the aromaticity and average size of aromatic cluster are inversely proportional to the oil shale density. For Longkou, Huadian and Beipiao oil shales with different densities, thechange rules of aromatic and aliphatic structures with the density are similar, indicating that these change rulesare independent of the grade and origin of oil shale. The change rules of heteroatom species in Beipiao oil shaleare different from that of Longkou and Huadian oil shales. 展开更多
关键词 Oil shale DENSITY Kerogens structural features
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Structural features of crust-mantle assemblage in the lithosphere along the Longitudinal Seismic Belt of China and their tectonic effect
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作者 毛桐恩 刘占坡 +3 位作者 徐常芳 张洪魁 余素荣 雷孟京 《Acta Seismologica Sinica(English Edition)》 CSCD 1998年第2期55-62,共8页
The 1°×1° distribution map of crustmantle structural ratio R for the lithosphere along the Longitudinal Seismic Belt of China has been compiled using computer based on the results of geophysical prospec... The 1°×1° distribution map of crustmantle structural ratio R for the lithosphere along the Longitudinal Seismic Belt of China has been compiled using computer based on the results of geophysical prospecting by previous researchers, and the latest results by the present authors. Based on this map, an insight into the structural features of the crustmantle assemblage along the Longitudinal Seismic Belt has been gained, while their relation to seismic activity and the distributions of geothermal flux and intracrustal high conductivitylow velocity layers, as well as their tectonic effect to seismicity have been discussed. 展开更多
关键词 lithosphere Longitudinal Seismic Belt structural features of crustmantle assemblage tectonic effect high conductivitylow velocity layer
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Structural features and thermoelectric performance of Sb- and Bi-doped Cu_(2)SnSe_(3) compounds 被引量:2
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作者 Shu-Ping Deng Xian-Yan Jiang +5 位作者 Li-Li Chen Zi-Ye Zhang Ning Qi Yi-Chu Wu Xin-Feng Tang Zhi-Quan Chen 《Rare Metals》 SCIE EI CAS CSCD 2021年第9期2474-2485,共12页
In this paper, a series of Sb-doped and Bi-doped Cu_(2)Sn_(1-x)M_(x)Se_(3) samples(M = Sb, Bi) are prepared by vacuum melting combined with the spark plasma sintering process. The effects of different atomic doping am... In this paper, a series of Sb-doped and Bi-doped Cu_(2)Sn_(1-x)M_(x)Se_(3) samples(M = Sb, Bi) are prepared by vacuum melting combined with the spark plasma sintering process. The effects of different atomic doping amounts on their properties are discussed. Structural studies indicate that all obtained samples comprise a single Cu_(2)SnSe_(3) phase. Sb and Bi atoms are experimentally demonstrated to be efficient cation dopants for increasing the transport performance. Compared with that doping on the cation site,Bi doping is much more efficient in increasing the electron concentration of the Cu_(2)SnSe_(3) system. Ultimately, a high figure of merit of 0.36 is achieved in the Cu_(2)Sn_(0.94)Sb_(0.06) Se_(3) sample at 773 K due to the enhanced power factor and lowered lattice thermal conductivity,which are 1.73 times higher than those of the pure sample.Our results provide an efficient approach to enhance thermoelectric performance via other doping atoms, which could also be applied to copper-based chalcogenide materials. 展开更多
关键词 Thermoelectric properties Positron annihilation spectroscopy Ternary copper chalcogenide Structure features DOPING POLYCRYSTALLINE
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Structural features of a polysaccharide from the leaves of Thea sinensis^+
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作者 FANG, Ji-Nian ZHANG, Zhi-Hua +1 位作者 SONG, Guo-Qiang LIU, Bai-Nian, Shanghai Institute of Materia Madica, The Chinese Academy of Sciences, Shanghai 200031 《Chinese Journal of Chemistry》 SCIE CAS CSCD 1991年第6期547-551,共0页
A polysaccharide of Thea sinensis, TSA, has been isolated from the fresh leaves as a major fraction of polysaccharides. The mol. wt. was estimated to be 850,000 with [α]_D^(15)+ 25.5°(c=0.75, H_2O). The componen... A polysaccharide of Thea sinensis, TSA, has been isolated from the fresh leaves as a major fraction of polysaccharides. The mol. wt. was estimated to be 850,000 with [α]_D^(15)+ 25.5°(c=0.75, H_2O). The component sugars were determined as L-rhamnose, L-arabinose, and D-galactose in molar ratio of 0.54: 1.0: 0.94. The O-acetyl groups locating on galactose residues position 2 were also iden- tified and the content was 3.8%. The ^(13)C NMR spectrum and CrO_3 oxidation of TSA indicated the Rhamnose, Arabinose and Galactose to be in α-, α- and β-configurations, respectively. Me- thylation analysis, periodate oxidation, partial hydrolysis and ^(13) C NMR. spectrum showed that TSA. is a branched galactoarabinan. 展开更多
关键词 structural features of a polysaccharide from the leaves of Thea sinensis
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The Thermodynamic and Dynamical Features of Double Front Structures During 21-31 July 1998 in China 被引量:7
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作者 周玉淑 邓国 +1 位作者 雷霆 琚建华 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2005年第6期924-935,共12页
The daily 1°× 1° data of the Aviation (AVN) model, the black body temperature (TBB) data of cloud top, and cloud images by geostationary meteorological satellite (GMS) are used to identify a dew-p... The daily 1°× 1° data of the Aviation (AVN) model, the black body temperature (TBB) data of cloud top, and cloud images by geostationary meteorological satellite (GMS) are used to identify a dew-point front near the periphery of the western Pacific subtropical high (WPSH). The results clearly demonstrate the existence of the dew-point front, and its thermodynamic and dynamic structural characteristics are analyzed in detail. The dew-point front is a transitional belt between the moist southwest monsoon flow and the dry adiabatic sinking flow near the WPSH, manifested by a large horizontal moisture gradient in the mid-lower troposphere and conjugated with the mei-yu front to form a predominant double-front structure associated with intense rainfall in the mei-yu period. The mei-yu front is located between 30° and 35°N, vertically extends from the ground level to the upper level and shifts northward. The dew-point front is to the south of the mei-yu front and lies up against the periphery of the WPSH. Generally, it is located between 850 hPa and 500 hPa. On the dew-point front side, the southwesterly prevails at the lower level and the northeasterly at the upper level; this wind distribution is different from that on the mei-yu front side. Vertical ascending motion exists between the two fronts, and there are descending motions on the north side of the mei^yu front and on the south side of the dew-point front~ which form a secondary circulation. The dynamics of the double fronts also have some interesting features. At the lower level, positive vertical vorticity and obvious convergence between the two fronts are clearly identified. At the mid-lower level, negative local change of the divergence (corresponding to increasing convergence) is often embedded in the two fronts or against the mei-yu front. Most cloud clusters occur between the two fronts and propagate down stream in a wave-like manner. 展开更多
关键词 double-front structure mei-yu front system structural features
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STRUCTURE FEATURES AND COMPOSITE ANALYSIS OF CONVECTIVE CELLS IN A WARM SECTOR HEAVY RAINFALL EVENT OVER SOUTHERN CHINA 被引量:1
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作者 钱磊 丁治英 +1 位作者 赵向军 夏蘩 《Journal of Tropical Meteorology》 SCIE 2017年第3期245-258,共14页
This paper uses the ARW-WRF model to carry out a numerical simulation of a warm-sector heavy rainfall event over southern China on the 22-23 May, 2014. A composite analysis method was used to analyze the evolution pro... This paper uses the ARW-WRF model to carry out a numerical simulation of a warm-sector heavy rainfall event over southern China on the 22-23 May, 2014. A composite analysis method was used to analyze the evolution process and structural features of the convective cells on a convection line during this rainfall event. This analysis identified three stages:(1) Stage of activation: the equivalent potential temperature surfaces as lower layers start to bulge and form warm cells and weak vertical convective cloud towers which are subject to the impact of low-level warm moist updrafts in the rainfall sector;(2) Stage of development: the warm cells continue to bulge and form warm air columns and the convective cloud towers develop upwards becoming stronger as they rise;(3) Stage of maturity: the warm air columns start to connect with the stable layer in the upper air; the convective cloud tower will bend and tilt westward with each increasing in height, and the convection cell is characterized by a "crescent-shaped echo" above the 700 h Pa plane. During this stage the internal temperature of the cell is higher than the ambient temperature and the dynamic structural field is manifested as intensive vertical upward movement. The large-value centers of the northerly and westerly winds in the middle layer correspond to the warm moist center in the cells and the relatively cold center south of the warm air column. Further analysis shows that the formation of the "crescent-shaped" convective cell is associated with horizontal vorticity. Horizontal vorticity in the center and west of the warm cell experiences stronger cyclonic and anticyclonic shear transformation over time; this not only causes the original suborbicular cell echo shape to develop into a crescent-like shape, but also makes a convection line consisting of cells that develop to the northwest. 展开更多
关键词 convective cells structural features horizontal vorticity composite analysis
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Predictive modeling of critical temperatures in magnesium compounds using transfer learning
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作者 Surjeet Kumar Russlan Jaafreh +4 位作者 Subhajit Dutta Jung Hyeon Yoo Santiago Pereznieto Kotiba Hamad Dae Ho Yoon 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第4期1540-1553,共14页
This study presents a transfer learning approach for discovering potential Mg-based superconductors utilizing a comprehensive target dataset.Initially,a large source dataset(Bandgap dataset)comprising approximately∼7... This study presents a transfer learning approach for discovering potential Mg-based superconductors utilizing a comprehensive target dataset.Initially,a large source dataset(Bandgap dataset)comprising approximately∼75k compounds is utilized for pretraining,followed by fine-tuning with a smaller Critical Temperature(T_(c))dataset containing∼300 compounds.Comparatively,there is a significant improvement in the performance of the transfer learning model over the traditional deep learning(DL)model in predicting Tc.Subsequently,the transfer learning model is applied to predict the properties of approximately 150k compounds.Predictions are validated computationally using density functional theory(DFT)calculations based on lattice dynamics-related theory.Moreover,to demonstrate the extended predictive capability of the transfer learning model for new materials,a pool of virtual compounds derived from prototype crystal structures from the Materials Project(MP)database is generated.T_(c) predictions are obtained for∼3600 virtual compounds,which underwent screening for electroneutrality and thermodynamic stability.An Extra Trees-based model is trained to utilize E_(hull)values to obtain thermodynamically stable materials,employing a dataset containing Ehull values for approximately 150k materials for training.Materials with Ehull values exceeding 5 meV/atom were filtered out,resulting in a refined list of potential Mg-based superconductors.This study showcases the effectiveness of transfer learning in predicting superconducting properties and highlights its potential for accelerating the discovery of Mg-based materials in the field of superconductivity. 展开更多
关键词 SUPERCONDUCTIVITY Critical temperature Transfer learning Crystal structure features Thermodynamic stability
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In Silico Investigation of Agonist Activity of a Structurally Diverse Set of Drugs to hPXR Using HM-BSM and HM-PNN
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作者 张一鸣 常美佳 +1 位作者 杨旭曙 韩晓 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2016年第3期463-468,共6页
The human pregnane X receptor(hPXR) plays a critical role in the metabolism, transport and clearance of xenobiotics in the liver and intestine. The hPXR can be activated by a structurally diverse of drugs to initiat... The human pregnane X receptor(hPXR) plays a critical role in the metabolism, transport and clearance of xenobiotics in the liver and intestine. The hPXR can be activated by a structurally diverse of drugs to initiate clinically relevant drug-drug interactions. In this article, in silico investigation was performed on a structurally diverse set of drugs to identify critical structural features greatly related to their agonist activity towards h PXR. Heuristic method(HM)-Best Subset Modeling(BSM) and HM-Polynomial Neural Networks(PNN) were utilized to develop the linear and non-linear quantitative structure-activity relationship models. The applicability domain(AD) of the models was assessed by Williams plot. Statistically reliable models with good predictive power and explain were achieved(for HM-BSM, r^2=0.881, q^2_(LOO)=0.797, q^2_(EXT)=0.674; for HM-PNN, r^2=0.882, q^2_(LOO)=0.856, q^2_(EXT)=0.655). The developed models indicated that molecular aromatic and electric property, molecular weight and complexity may govern agonist activity of a structurally diverse set of drugs to h PXR. 展开更多
关键词 human pregnane X receptor agonist activity heuristic method-Best Subset Modeling heu ristic method-Polynomial Neural Networks structural features quantitative structure-activity relation ship
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Basic Features of the Crustal Structure in the Lower Yangtze and Its Neighboring Area in the Chinese Mainland: Review of Deep Seismic Sounding Research 被引量:3
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作者 Bai Zhiming Wu Qingju +1 位作者 Xu Tao Wang Xiao 《Earthquake Research in China》 CSCD 2016年第3期298-315,共18页
The Deep Seismic Sounding( DSS) projects carried out from the 1970 s in the lower Yangtze region and its neighboring area were reviewed in this paper,then the basic wave group features of those wide angle reflection /... The Deep Seismic Sounding( DSS) projects carried out from the 1970 s in the lower Yangtze region and its neighboring area were reviewed in this paper,then the basic wave group features of those wide angle reflection / refraction record sections,and of the crustal structure are summarized. It shows that there were in total five clear wave groups on the record sections,which include the first arrival Pg,the reflection P1 from the bottom interface of the upper crust,the reflection P3 from the bottom interface of the middle crust,the strong reflection Pm from the Moho boundary,and the refraction Pn from uppermost mantle. In general,these phases are easily consistently traced and compared,despite some first arrivals being delayed or arriving earlier than normal due to the shallow sedimentary cover or bedrocks. In particular,in the Dabie Mountain region the seismic events of a few gathered shots always have weak reflection energy,are twisted,or exhibit disorganized waveforms, which could be attributed to the disruption variations of reflection depth,the broken Moho,and the discontinuity of the reflection boundary within crust. The regional crustal structures are composed of the upper,middle and lower crust,of which the middle and lower layers can be divided into two weak reflection ones. The crustal thickness of the North China and Yangtze platform are 30km- 36 km,and the Moho exhibits a flat geometry despite some local uplifts. The average pressure velocity in lower crust beneath this two tectonic area is 6. 7 ± 0. 3km / s. Nevertheless,beneath the Dabieshan area the crustal thickness is 32km- 41 km,the Moho bends down sharply andtakes an abrupt 4km- 7km dislocation in the vertical direction. The average pressure velocity in the lower crust beneath the Dabieshan area is 6. 8 ± 0. 2km / s. 展开更多
关键词 Deep seismic sounding projects Wave group feature Crustal structure feature Anhui Province and its neighboring area
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Ore-controlling Regularities of Thrust-fold structures and features of Tectono-geochemical Anomalies at the Xiaozhuqing Exploration Area in the Huize Zn-Pb District
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作者 Gong Hongsheng Han Runsheng +2 位作者 Li Ziteng Ren Tao Wang Jiasheng 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2017年第S1期202-203,共2页
1 Introduction The huize Zn-Pb ore district in Yunnan province is locatedinthecentralsouthernofthe Sichuan—Yunnan—GuizhouPb-ZnPoly-metallic Mineralization Area in the southwestern margin of the Yangtze Block,and is ... 1 Introduction The huize Zn-Pb ore district in Yunnan province is locatedinthecentralsouthernofthe Sichuan—Yunnan—GuizhouPb-ZnPoly-metallic Mineralization Area in the southwestern margin of the Yangtze Block,and is strictly controlled by fault structures.It has developed to one of the famous production bases of lead&zinc and germanium in China. 展开更多
关键词 PB Ore-controlling Regularities of Thrust-fold structures and features of Tectono-geochemical Anomalies at the Xiaozhuqing Exploration Area in the Huize Zn-Pb District Zn
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Structural Control of the Getang Carlin-Type Gold Deposit in Southwest China
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作者 Guoping Zeng Xinlu Hu +3 位作者 Diwei Luo Jianzhong Liu Shuzhen Yao Yongjie Jin 《Journal of Earth Science》 SCIE CAS CSCD 2024年第2期536-552,共17页
The Getang is a representative Carlin-type gold deposit in Southwest China.It has a proven reserve of about 30 tonnes at an average grade of 5.1 g/t Au.The orebodies occur as strat-abound lenses,and are structurally c... The Getang is a representative Carlin-type gold deposit in Southwest China.It has a proven reserve of about 30 tonnes at an average grade of 5.1 g/t Au.The orebodies occur as strat-abound lenses,and are structurally controlled by shallow NWW-and NE-trending fold-fault systems and the unconformity between the Upper and Middle Permian.In this study,the regional-and deposit-scale structural investigations,joints and finite strain measurements,and stress and dynamic analysis were conducted with an aim to reveal the structural process of the Getang gold deposit and clarify the relationship between the gold mineralization and structures.Three phases of deformation were identified in the deposit:(1)paleokarst was generated by a crustal uplift when the Youjiang Basin experienced extension at the end of the Middle Permian,laying the foundation for the unconformity;(2)the NW-trending structures were formed under a NNE-SSW compression during the Indochina-South China collision(Indosinian orogeny)in Triassic;(3)the NE-trending structures were generated or reactivated under a NW-SE-oriented compression during the Yanshanian intracontinental orogeny.The unconformity recorded two episodes of tectonic evolution in the NNE-SSW and NW-SE directions.Structural analyses and geochronology data suggest that the Getang gold deposit was formed as a result of tectonic transition from compression to extension during the Yanshanian intracontinental orogeny. 展开更多
关键词 Carlin-type gold deposit structural features finite strain Getang Southwest China economy geology GEOCHEMISTRY
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Structure, Formation, Properties, and Application of Calcium and Magnesium Silicate Hydrates System—A Review
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作者 肖建敏 LI Hui HU Yaru 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第3期604-615,共12页
In order to expand the advantages of strong durability and high compressive strength of calcium silicate hydrates(C-S-H),at the same time to make up for the poor early mechanical strength of magnesium silicate hydrate... In order to expand the advantages of strong durability and high compressive strength of calcium silicate hydrates(C-S-H),at the same time to make up for the poor early mechanical strength of magnesium silicate hydrates (M-S-H),we present the features and advantages of C-S-H and M-S-H and a comprehensive review of the progress on CaO-MgO-SiO_(2)-H_(2)O.Moreover,we systematically describe natural calcium and magnesium silicate minerals and thermodynamic properties of CaO-MgO-SiO_(2)-H_(2)O.The effect of magnesium on C-S-H and calcium on M-S-H is summarized deeply;the formation and structural feature of CaO-MgO-SiO_(2)-H_(2)O is also explained in detail.Finally,the development of calcium and magnesium silicate hydrates in the future is pointed out,and the further research is discussed and estimated. 展开更多
关键词 calcium and magnesium silicate hydrates thermodynamic properties STABILITY structural feature
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Modified Ceria-Zirconia Fluorite-Like Catalysts for the Combustion of Methane
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作者 Tatiana Kuznetsova Vladislav Sadykov +5 位作者 Lubsan Batuev Ella Moroz Elena Burgina Vladimir Rogov Vladimir Kriventsov Dmitrii Kochubey 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2006年第3期149-163,共15页
For dispersed ceria-zirconia-based solid solutions prepared via the polymerized complex method and annealed at 700 ℃, effects of bulk doping by Ca, Mn, Co, Bi or Nb cations and surface modification by Mn and Pt on th... For dispersed ceria-zirconia-based solid solutions prepared via the polymerized complex method and annealed at 700 ℃, effects of bulk doping by Ca, Mn, Co, Bi or Nb cations and surface modification by Mn and Pt on their structural features, surface/bulk oxygen reactivity and catalytic activity in methane combustion are considered. With up to 20 mol% doping, a structural type of homogeneous solid solutions of anion-deficient fluorite with disordered anion vacancies is formed. Doping by transition metal cations or Pt increases the mobility and reactivity of the surface/bulk oxygen. A broad variation in specific rates of methane combustion for the studied systems was observed, suggesting structural sensitivity of this reaction. In general, there is no universal relationship between the oxygen mobility, the reactivity and the catalytic activity in methane combustion, which is explained by the factor of specific methane activation on surface active sites. For the Pt-promoted samples, Pt efficiency in methane activation depends on the Pt-support interaction, and the most favorable ones being mixed Pt/MnOx and Pt/NbOx clusters on the surface of the supports that exhibit high lattice oxygen mobilities. 展开更多
关键词 Ce-Zr-O Ca Mn Co Bi Nb structural features oxygen reactivity oxygen mobility methane combustion
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