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四川黄龙沟天然水中的深源CO_2与大规模的钙华沉积 被引量:18
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作者 刘再华 K Yoshimura +2 位作者 Y Inokura M Noto 曹云 《地球与环境》 CAS CSCD 北大核心 2005年第2期1-10,共10页
在有大规模钙华沉积的四川黄龙沟中,使用化学成分数据以及碳氧稳定同位素组成对其水文地球化学特征进行了分析研究。研究区钙华沉积的地表溪流水质基本上受到两种水混合的制约,即断层泉水和山区的融雪(冰)水。泉水中含有高浓度的经由断... 在有大规模钙华沉积的四川黄龙沟中,使用化学成分数据以及碳氧稳定同位素组成对其水文地球化学特征进行了分析研究。研究区钙华沉积的地表溪流水质基本上受到两种水混合的制约,即断层泉水和山区的融雪(冰)水。泉水中含有高浓度的经由断层提供的CO2,结果高浓度的溶解CO2使得其溶解的碳酸盐岩比普通的岩溶泉溶解的碳酸盐岩高得多,同时也导致硅酸盐岩的溶解。黄龙沟中上游的泉水相对于方解石接近于平衡。溶解无机碳(DIC)的浓度和它们的δ13C值是大约由c=0.02mol·L1δ13C=-3‰的CO2(aq)与含有δ13C=+3‰的碳酸盐岩在封闭系统条件下反应的结果。估计这些CO2中约有70%来自上地幔。所有泉水的水化学数据均落在高岭石稳定域内,但对Na长石和Ca长石具有侵蚀性。由于这些长石矿物的溶解速率太慢,所以水中的化学成分远离长石稳定域。地表溪流的DIC种类之间达到同位素平衡,在不同观测点发现的δ13CDIC变化主要是由于从水中释放出的CO2的程度不同引起的。水样的δ18O值与其采集点的海拔高度之间存在线性关系;研究区的地表溪流的氧同位素组成受到蒸发的制约。在流经钙华沉积物的地表溪流中白天和夜晚的水化学及pH的日变化表明生物作用促进了碳酸盐的沉积,尽管作用不显著。据估计研究区碳酸钙的日沉积速率是4778kg·km2,即约1mm·a1。 展开更多
关键词 钙华沉积 CO2 黄龙 规模 四川 天然水 水文地球化学特征 深源 碳酸盐岩 δ^13C值 氧同位素组成 溶解无机碳 同位素平衡 研究区 成分数据 硅酸盐岩 封闭系统 化学数据 溶解速率 长石矿物 化学成分 线性关系 海拔高度 生物作用
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Petrochemistry ,Chronology and Tectonic Setting of Strong Peraluminous Anatectic Granitoids in Yunkai Orogenic Belt , Western Guangdong Province ,China 被引量:7
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作者 彭松柏 金振民 +4 位作者 刘云华 付建明 何龙清 蔡明海 王彦斌 《Journal of China University of Geosciences》 SCIE CSCD 2006年第1期1-12,共12页
Arguments persist on the genesis and ages for the banded-augen (rapakivi) anatectic granitoids (charnockite) extensively outcropped in the Yunkai (云开) region, western Guangdong (广东) Province. Their petroch... Arguments persist on the genesis and ages for the banded-augen (rapakivi) anatectic granitoids (charnockite) extensively outcropped in the Yunkai (云开) region, western Guangdong (广东) Province. Their petrochemistry, SHRIMP dating, deformational and metamorphic structure were studled. The results show that most granitoids are A/CNK〉1. 1, CaO/Na2O= 0. 62-1. 61 (average 0.94〉0.3), Al2O3/TiO2 =16.6-60.6 (average 23.68), depleted high field strong elements Ta, Nb, Zr, strong peraluminous high-K calcalkaline and calcalkaline granitoids in the post-collisional tectonic environment of a subduction-collision orogenic belt in an active-continental margin. The temperatures of charnockite and gneissic garnet-bearing biotite monzonitic granite are obviously higher than those of banded-augen (rapakivi) biotite monzonitic granite, and charnockite and gneissic garnet-bearing biotite monzonitic granite with the evolutional characteristics of A-type granites. The forming ages from banded-augen (rapakivi) biotite monzonitic granite to charnockite and gneissic garnet-bearing biotite monzonitic granite, whose crystallizing zircon SHRIMP ages are (465±10) Ma, (467±10 ) Ma, (435±11 ) Ma and (413±8) Ma, respectively, become younger. This shows that there was an oceaniccontinental subduction-collision and post-collisional extension-delamination-underplating between the Yangtze and Cathaysia plates during the Caledonian, and the granitoids experienced compressional uplift and extensional exhumation during the lndosinian. This provides important evidence of subduction collision of the Yangtze plate to the Cathaysia plate during the Caledonian in South China. 展开更多
关键词 Yunkai orogenic belt CALEDONIAN strong peraluminous anatectic granitoids postcollisional tectonic environment extension-delamination-undcrplating
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Petrography and Geochemistry of Peridotite Xenoliths from Hannuoba and Significance for Lithospheric Mantle Evolution 被引量:3
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作者 余淳梅 郑建平 Griffin WL 《Journal of China University of Geosciences》 SCIE CSCD 2006年第1期25-33,共9页
The compositions of the whole rocks and trace elements of minerals in peridotites can reflect the characteristics of the lithospheric mantle. The nature and evolution of the Cenozoic lithospheric mantle beneath Hannuo... The compositions of the whole rocks and trace elements of minerals in peridotites can reflect the characteristics of the lithospheric mantle. The nature and evolution of the Cenozoic lithospheric mantle beneath Hannuoba (汉诺坝), located on the north edge of the intra-North China orogenic belt, are discussed based on the in-situ LAM-ICPMS detected trace element compositions of clinopyroxenes in the Hannuoba peridotitic xenoliths combined with detailed petrography and geochemistry studies. The Hannuoba lithospheric mantle was formed by different partial meltings of the primitive mantle. Most of the samples reflect the partial melting degree of lower than 5% with a few samples of 15%-20%. Major element compositions of the whole rocks and geochemical compositions of clinopyroxenes reveal the coexistence of both fertile and depleted mantle underneath the Hannuoba region during the Cenozoic. This was probably caused by the asthenospheric mantle replacing the aged craton mantle through erosion, intermingling and modification. Our conclusion is further supported by the existence of both carbonatitic magmatic material and silicate melt/ fluid metasomatism as magnified by the trace elements of the clinopyroxencs from the Hannuoba lithospherJc mantle. 展开更多
关键词 peridotite xenoliths LAM-ICPMS lithospheric mantle evolution HANNUOBA North China craton
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Estimation of a basal area growth model for individual trees in uneven-aged Caspian mixed species forests 被引量:1
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作者 Zohreh Mohammadi Soleiman Mohammadi Limaei +1 位作者 Peter Lohmander Leif Olsson 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第5期1205-1214,共10页
The aim of this study was to estimate a basal area growth model for individual trees in uneven-aged Caspian forests.A survey was conducted in order to find a natural forest without any harvesting activities,a so call... The aim of this study was to estimate a basal area growth model for individual trees in uneven-aged Caspian forests.A survey was conducted in order to find a natural forest without any harvesting activities,a so called 'untouched forest' and an area was selected from the Iranian Caspian forest.Three sample plots in the same aspect and of the same forest type were selected.In each plot,total tree height,diameter at breast height,distance of neighbor trees and azimuth were measured.Thirty trees were selected and drilled with increment borer to determine the increment model.Regression analysis was used to estimate the growth model.Results show that,for individual trees,there is a significant nonlinear relationship between the annual basal area increment,as the dependent variable,and the basal area.The results also show that the basal area of competing trees has a positive influence on growth.That the increment is higher with more competing neighboring trees is possibly because plots with higher volume per hectare and more competition,most likely also have higher site index or better soil or better site productivity than the plot with lower volume per hectare. 展开更多
关键词 Basal area increment Diameter growth Regression analysis Caspian forests
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The diurnal variation pattern of choroidal thickness in macular region of young healthy female individuals using spectral domain optical coherence tomography 被引量:1
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作者 Mcng Zhao Xiu-Fcn Yang +4 位作者 Xuan Jiao Apiradee Lim Xue-Tao Ren Torkel Snellingen Ning-Pu Liu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第4期561-566,共6页
AIM: To investigate the pattern of diurnal variations of choroidal thickness of macular region of healthy individuals. ~ METHODS: A prospective study of 32 healthy female subjects was conducted. Each subject underwe... AIM: To investigate the pattern of diurnal variations of choroidal thickness of macular region of healthy individuals. ~ METHODS: A prospective study of 32 healthy female subjects was conducted. Each subject underwent 1) a questionnaire on daily schedule, 2) the Pittsburgh Sleep Quality Index questionnaire (PSQI), and 3) ocular examinations including an eye dominance test, fundus photography, and sequential optical coherence tomography (OCT) imaging, on two separate days at five fixed 3h time intervals. Choroidal thickness was measured by two masked graders. RESULTS: A significant diurnal variation of choriodal thickness at fovea (P〈0.001), at 500 μm nasal (P〈0.001), temporal to fovea (P=0.01) or 1500 μm nasal to fovea (P= 0.001) was observed. The median choroidal thickness peaked at 11:00 at fovea (P=0.01), at 500μm nasal (P = 0.009) and temporal (P=0.03) to fovea. The median amplitude of foveal choroidal thickness was 20.5 pm (13, 31) and 20.0 μm (12.5, 28.2) for the first and second series of measurements, respectively. The greater amplitude of foveal choroidal thickness was associated with thickner initial foveal choroidal thickness [ 0.05 (0.03, 0.08), P= 0.01], dominant eye 10.51 (4.02, 14.60), P=0.04] in the multivariate linear regression. CONCLUSION: Our data show a significant diurnal variation of the choroidal thickness at fovea, at 500 μm nasal and temporal to fovea and 1500 μm nasal to fovea. Thicker initial foveal choroidal thickness and being dominant eye may influence the amplitude of foveal choroidal thickness. 展开更多
关键词 choroidal thickness diurnal variation optical coherence tomography
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Distribution and Geochemical Implication of Aromatic Hydrocarbons across the Meishan Permian-Triassic Boundary 被引量:1
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作者 黄咸雨 焦丹 +2 位作者 鲁立强 黄俊华 谢树成 《Journal of China University of Geosciences》 SCIE CSCD 2006年第1期49-54,共6页
Aromatic compounds extracted from sedimentary rocks can reflect environmental conditions, organic sources and maturity. The aromatics, identified in association with mass extinction in particular, would provide a sign... Aromatic compounds extracted from sedimentary rocks can reflect environmental conditions, organic sources and maturity. The aromatics, identified in association with mass extinction in particular, would provide a signature assisting our understanding of the causes of the biotic crisis. Aromatic hydrocarbons were fractionated from the total lipid extracts of 37 samples taken from the PermianTriassic boundary (beds 23 to 34) of section B at Meishan (煤山), Zhejiang (浙江) Province in South China. These aromatics were analyzed by using gas chromatography-mass spectrometry (GC-MS). Main compounds identified include naphthalene, phenanthrenes, fluorene, dibenzothiophene, dibenzofuran, fluoranthene, pyrene and some of their methyl homologues. The indices of methyl phenanthrene distribution fraction indicate the comparable maturity (within the oil window, 0.7%-1.0% of the mean vitfinite reflectance) of the organic matter throughout the whole profile analyzed. The ratio of dibenzothiophene to phenanthrene (DBT/PHN) varies generally at a comparable pace with lithology. Significantly, a gradual decrease of this ratio was observed within bed 24 limestone, which is probably due to the variation of sedimentary environment. This change is in line with the drop in the carbon isotope composition of carbonate, the loss of the Changhsingian reef ecosystem, and the decrease of cyanobacteria abundance within the bacteria population. The coincidence of these records suggests a close relation between the biotic crisis and marine environmental conditions, and these records clearly show the onset of the biotic crisis prior to event bed 25. 展开更多
关键词 MEISHAN Permian-Triassic boundary aromatic hydrocarbons molecular fossil DIBENZOTHIOPHENE fluorene series PALEOENVIRONMENT
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Pharmacokinetic comparison among resveratrol and some of its naturally occurring analogs
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作者 Hai-shuLIN SamuelChaoMingYEO WanCHEN 《中国药理学与毒理学杂志》 CAS CSCD 北大核心 2015年第S1期108-108,共1页
OBJECTIVE To elucidate the structural-pharmacokinetic relationship and identify resveratrol analogs with favorable pharmacokinetic profiles for potential medicinal application. METHODS The pharmacokinetic data of resv... OBJECTIVE To elucidate the structural-pharmacokinetic relationship and identify resveratrol analogs with favorable pharmacokinetic profiles for potential medicinal application. METHODS The pharmacokinetic data of resveratrol(trans-3,5,4-trihydroxystilbene),pterostilbene(trans-3,5-dimethoxy-4-hydroxystilbene),resveratrol trimethyl ether(trans-3,5,4-trimethoxystilbene)and some other herbal resveratrol analogs were extracted from the authors′recent publications and compared.RESULTS Aqueous solubility,to different extent,has been identified as a barrier to oral absorption of resveratrol and its analogs.In addition,the para hydroxyl group(s)on the aromatic ring was less liable to metabolism compared to the meta-hydroxyl group(s).Pterostilbene and resveratrol trimethyl ether displayed more superior pharmacokinetic properties than resveratrol,i.e.much slower clearance and abundant plasma exposure.CONCLUSION Pterostilbene appears to be a favorable candidate for further development.Resveratrol analogs with meta-hydroxyl group(s)might have poor metabolic stability and suffer from rapid clearance and low oral bioavailability. 展开更多
关键词 RESVERATROL PTEROSTILBENE RESVERATROL trimethyl ET
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New and Facile Synthesis of Substituted Pyrrole, Pyridine, Pyrazolo[4,3-b] Pyridine, Pyrano[3,2-c] Quinoline, Napthopyran, Naphthodipyran and Coumarin Derivatives
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作者 F. M. A. El-Taweel A. A. Elagamey 《International Journal of Organic Chemistry》 2013年第1期58-70,共13页
Several new pyrazolo[4,3-b] pyridines 7a, b were prepared by reacting arylidenemalononitriles 1a, c or 1i, j with 4-nitrosoantipyrine 4. Reacting 1a, b, d with 4-azidomethylcarbonylantipyrine 8 give 2-aminopyrrole 14.... Several new pyrazolo[4,3-b] pyridines 7a, b were prepared by reacting arylidenemalononitriles 1a, c or 1i, j with 4-nitrosoantipyrine 4. Reacting 1a, b, d with 4-azidomethylcarbonylantipyrine 8 give 2-aminopyrrole 14. Pyrano[3,2-c] quinolines 20a, b and 23 were obtained by reacting 4-hydroxyquinoline 15 with 1g, h, 2b respectively. Reaction of 1 with naphthalenediols 24, 27 and 29 yield naphthodipyrans 26a, b, 28a, b and 30a。 展开更多
关键词 PYRROLE PYRIDINE Pyrazolo[4 3-b] PYRIDINE Pyrano[3 2-c] QUINOLINE NAPHTHOPYRAN Naphthodipyrans and Coumarin
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Crystal Structure, Thermal Behavior and Vibrational Spectra of 4,4’Diamoniumdiphenylmethan Sulfate Hydrate
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作者 Takoua Ben Issa Latifa Benhamada 《Open Journal of Inorganic Chemistry》 2017年第2期61-73,共13页
Single crystals of the 4,4’-diamoniumdiphenylmethan sulfate hydrate, denoted DDPS, were grown by slow evaporation solution technique at room temperature. The compound was characterized by single crystal X-ray diffrac... Single crystals of the 4,4’-diamoniumdiphenylmethan sulfate hydrate, denoted DDPS, were grown by slow evaporation solution technique at room temperature. The compound was characterized by single crystal X-ray diffraction, IR and thermal analysis (TG-DTA). It crystallizes in the monoclinic system (space group C2/c) with the following unit cell dimensions: a = 17.7635(10) ?, b = 9.3796(10) ?, c = 27.5676(10) ?, β = 97.37(2)°, V = 4555.2(6) ?. The structure was solved by the direct method and refined to final R value of 0.0472 for 2108 independent reflections. The anions are hydrogen bonded to each other, forming clusters [HS2O8]3﹣ parallel to the plan (a, b). The water molecules connect these clusters via O-H···O hydrogen bonds. The organic cations are attached to the clusters through N-H···O hydrogen bonds, forming an infinite three-dimensional network. 展开更多
关键词 Organic SULFATE CRYSTALLINE Structure VIBRATIONAL Spectra THERMAL Behavior Differential THERMAL Analysis
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Long aseismic slip duration of the 2006 Java tsunami earthquake based on GPS data
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作者 Rio Raharja Endra Gunawan +2 位作者 Irwan Meilano Hasanuddin Z.Abidin Joni Efendi 《Earthquake Science》 CSCD 2016年第5期291-298,共8页
The Java earthquake occurred on July 17, 2006 with magnitude 7.8 associated to the subduction process of Indo-Australian plate and Sundaland block off southwestern coast of Java. We present postseismic deformation par... The Java earthquake occurred on July 17, 2006 with magnitude 7.8 associated to the subduction process of Indo-Australian plate and Sundaland block off southwestern coast of Java. We present postseismic deformation parameters of the 2006 Java earthquake analyzed using campaign GPS observation from 2006 to 2008 and continuous observation from 2007 to 2014. We use an analytical approach of logarithmic and exponential functions to model these GPS data. We find that the decay time in the order of hundreds of days after the mainshock as observed by 8 years' data after the mainshock for magnitude 7 earthquake is longer than a general megathrust earthquake event. Our findings suggest that the 2006 Java earthquake which is considered as "tsunami earthquake" most probably occurred in the region that has low rigidity and tends to continuously slip for long time periods. 展开更多
关键词 2006 Java earthquake Aseismic slip GPS Time series
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On The Cauchy Problem For Some Parabolic Fractional Partial Differential Equations With Time Delays
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作者 Mahmoud M.El-Borai Wagdy G.El-Sayed Faez N. Ghaffoori 《Journal of Mathematics and System Science》 2016年第5期194-199,共6页
The Cauchy problem for some parabolic fractional partial differential equation of higher orders and with time delays is considered. The existence and unique solution of this problem is studied. Some smoothness propert... The Cauchy problem for some parabolic fractional partial differential equation of higher orders and with time delays is considered. The existence and unique solution of this problem is studied. Some smoothness properties with respect to the parameters of these delay fractional differential equations are considered. 展开更多
关键词 Cauchy problem- fractional partial differential equations with time delays- successive approximations.
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The Thermal Properties of Natural Pozzolan and Energy Efficiency in Buildings
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作者 Hamadache Miloud M. Mouli +3 位作者 N. Bouhamou O. Chaib A. S. Benosman F. Dif 《Journal of Control Science and Engineering》 2014年第2期120-127,共8页
The objective of this work is the study of recoverability of materials. It consists in studying the effectiveness of the addition of natural pozzolan on the thermal properties of the mortar. To do this, measuring inst... The objective of this work is the study of recoverability of materials. It consists in studying the effectiveness of the addition of natural pozzolan on the thermal properties of the mortar. To do this, measuring instruments were installed to quantify the overall indoor environment and in particular the thermal environment. Given that the thermal environment is characterized by the physical quantities: the temperature of air, wall temperature and the air humidity. This allows gauging the level of the energy consumption and thermal behavior of the envelope of structure in order to verify the conformity of the housing to the requirements of thermal comfort. For this, we measured the thermal conductivity of mortars containing different contents of pozzolan (10%, 20%, 30%). So, the results showed the beneficial effect ofpozzolan as thermal insulator by comparing with other insulation materials. 展开更多
关键词 Pozzolan mortar thermal conductivity energy of the building.
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Pollutant emissions from biomass burning:A review on emission characteristics,environmental impacts,and research perspectives
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作者 Ke Jiang Ran Xing +8 位作者 Zhihan Luo Wenxuan Huang Fan Yi Yatai Men Nan Zhao Zhaofeng Chang jinfeng Zhao Bo Pan Guofeng shen 《Particuology》 SCIE EI CAS CSCD 2024年第2期296-309,共14页
Biomass is one most abundant resource on the earth providing important energies in support of so-cioeconomic development in many areas.Burning of biomass fuels comprises to nearly 10%of the total energy from anthropog... Biomass is one most abundant resource on the earth providing important energies in support of so-cioeconomic development in many areas.Burning of biomass fuels comprises to nearly 10%of the total energy from anthropogenic combustion processes:however,as the burning is usually incomplete,this process yields products of incomplete combustion posing consequently significant impacts on air quality,human health,and climate change.Here,we analyzed spatiotemporal characteristics in intentional and unintentional biomass burning from different sectors,discussed impacts of biomass burning emissions on indoor and outdoor air quality,and consequent influences on human health.The global total con-sumption amount of biomass including both natural and anthropogenic sources was approximately 7900 Tg in 2019,with significantly large regional and sectorial discrepancies among regions.Globally,anthropogenic biomass burning amounts increased gradually,but notably in some developing countries like China residential consumption of biomass fuels,as one large sector of biomass use,decreased over time.Uncommercial biomass consumption needs to be accurately quantified.There are relatively rich datasets of pollutant emission factors from biomass burning,including laboratory and field tests,but still large variations exit and contribute substantially to the uncertainty in emission inventory.Global pri-mary PM2.5,black carbon and organic carbon emissions from biomass burning were about 51,4.6,and 29 Tg,respectively,contributing to nearly 70%,55%,and 90%of the total emission from all sources,and emissions from the residential sector and open fires are major sources.Brown carbon emissions from biomass burning attracts growing interests but available studies adopted different methodologies challenging the comparability of those results.Biomass burning emissions polluted not only ambient air but more severely indoor air quality,adversely affecting human health.Future studies that should be emphasized and promoted are suggested. 展开更多
关键词 Biomass burning Carbonaceous aerosol EMISSION Air quality Human health
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Effect of super-chilling storage on maintenance of quality and freshness of the Pacific oyster(Crassostrea gigas) 被引量:2
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作者 Shiliang Dong Yabin Niu +6 位作者 Huamao Wei Yumeng Lin Xin Lu Tetsuro Yamashita Kefeng Yu Koichi Takaki Chunhong Yuan 《Food Quality and Safety》 SCIE CSCD 2023年第2期217-225,共9页
The quality changes of shelled Pacific oysters(Crassostrea gigas)were examined in relation to the effects of superchilling storage at-1 C for 28 d by measuring changes in biochemical properties(microbial analysis,aden... The quality changes of shelled Pacific oysters(Crassostrea gigas)were examined in relation to the effects of superchilling storage at-1 C for 28 d by measuring changes in biochemical properties(microbial analysis,adenosine triphosphate(ATP)-related compounds,pH,free amino acids)and sensory evaluations in this study.The results indicated that microorganism growth was significantly inhibited during superchilling storage.Adenosine diphosphate(ADP)and adenosine monophosphate(AMP)accumulated while ATP rapidly decreased in the adductor muscle.ATP and ADP were the primary components in the other 3 tissues including mantle,gill,and body trunk of oysters,and they remained relatively stable over time.The pH and adenylate energy charge in the adductor muscle could be utilized as freshness indicators for shelled oysters.However,there were no significant differences(P>0.05)among the free amino acids during whole storage.According to the sensory evalu-ations,oysters could be alive and tolerated up to 21 d at-1℃storage.The study demonstrated that superchilling storage at-1℃could better maintain the eating quality of shelled oysters and the shelf life was extended to 21 d. 展开更多
关键词 Shelled oyster SUPERCHILLING ATP-related compounds sensory evaluations shelf life
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Ammonia Sensing System Based on Wavelength Modulation Spectroscopy 被引量:3
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作者 Duarte VIVEIROS Joao FERREIRA +5 位作者 Susana O. SILVA Joana RIBEIRO Deolinda FLORES Jose L. SANTOS Orlando FRAZAO Jose M. BAPTISTA 《Photonic Sensors》 SCIE EI CAS CSCD 2015年第2期109-115,共7页
A sensing system in the near infrared region has been developed for ammonia sensing based on the wavelength modulation spectroscopy (WMS) principle. The WMS is a rather sensitive technique for detecting atomic/molec... A sensing system in the near infrared region has been developed for ammonia sensing based on the wavelength modulation spectroscopy (WMS) principle. The WMS is a rather sensitive technique for detecting atomic/molecular species, presenting the advantage that it can be used in the near-infrared region by using the optical telecommunications technology. In this technique, the laser wavelength and intensity were modulated by applying a sine wave signal through the injection current, which allowed the shift of the detection bandwidth to higher frequencies where laser intensity noise was typically lower. Two multi-pass cells based on free space light propagation with 160 cm and 16 cm of optical path length were used, allowing the redundancy operation and technology validation. This system used a diode laser with an emission wavelength at 1512.21nm, where NH3 has a strong absorption line. The control of the NH3 gas sensing system, as well as acquisition, processing and data presentation was performed. 展开更多
关键词 Ammonia sensing fiber optic system near infrared region wavelength modulation spectroscopy environment
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Study of Stability Criteria of Numerical Solution of Ordinary and Partial Differential Equations Using Eulers and Finite Difference Scheme
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作者 AHMAD Najmuddin CHARAN Shiv 《Journal of Partial Differential Equations》 CSCD 2022年第3期281-288,共8页
In this paper we have discussed solution and stability analysis of ordinary and partial differential equation with boundary value problem.We investigated periodic stability in Eulers scheme and also discussed PDEs by ... In this paper we have discussed solution and stability analysis of ordinary and partial differential equation with boundary value problem.We investigated periodic stability in Eulers scheme and also discussed PDEs by finite difference scheme.Numerical example has been discussed finding nature of stability.All given result more accurate other than existing methods. 展开更多
关键词 STABILITY ordinary and partial differential equations Eulers and finite difference scheme
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Comparison between Merrifield–Simmons Index and Wiener Index of Graphs
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作者 Ke Xiang XU Kinkar Chandra DAS +1 位作者 Ivan GUTMAN Meng Lu WANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2022年第12期2220-2230,共11页
The Merrifield–Simmons indexσis the total number of independent vertex sets(including the empty set)of the graph G.The Wiener index W is the sum of distances in all unordered pairs of vertices of G.We construct some... The Merrifield–Simmons indexσis the total number of independent vertex sets(including the empty set)of the graph G.The Wiener index W is the sum of distances in all unordered pairs of vertices of G.We construct some new graphs satisfyingσ>W and W>σ,respectively.In particular,infinite graphs satisfying W>σare invented with graphs with diameter 2 and infinite ones satisfyingσ>W are discovered with so-called universally diametrical graphs. 展开更多
关键词 Merrifield–Simmons index Wiener index Cartesian product independence number Fibonacci number universally diametrical graph
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New prospective gas plays in pliocene sands, offshore Nile Delta Basin: A case study from Kamose-1 well at North Sinai Concession, Egypt
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作者 Mohammad Abdelfattah Sarhan Geology 《Petroleum Research》 2022年第3期329-340,共12页
The Pliocene sands in the offshore parts of the Nile Delta Basin represent significant gas reservoirs.Several targets have been recently discovered in different places along the offshore Nile Delta Basin.The present w... The Pliocene sands in the offshore parts of the Nile Delta Basin represent significant gas reservoirs.Several targets have been recently discovered in different places along the offshore Nile Delta Basin.The present work focuses on the possibility of discovering new natural gas resources at North Sinai Concession through an integrated method between seismic and well logs data interpretations.A case study from Kamose-1 Well at Kamose Field,North Sinai Concession has been examined.The quantitative explanation for the well log data of Kamose-1 Well has revealed two zones expected to be gas-bearing zones.These intervals are located between depths;1174–1186 m(zone I)and between 1429 and 1503 m(zone II).The calculated petrophysical parameters for these zones exhibit low water saturation(24–43%),high effective porosity(30–31%),low shale volume(21–26%),high total porosity(37–38%)and low bulk volume of water(0.07–0.12).Zone II(74 m thick)shows a clear bright spot on the seismic profiles covering the study area,while,zone I is beyond seismic resolution(12 m thick).Several seismic bright spots have been outlined on the seismic data nearby Kamose-1 Well.The comparison between the newly outlined seismic bright spots with the drilled one in Kamose-1 Well exhibited a great similarity.Accordingly,these prospects are expected to be new targets for gas exploration in the Pliocene succession at North Sinai Concession. 展开更多
关键词 Petrophysical evaluation Pliocene sands Seismic bright spot Kamose field Nile delta basin
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A cooperative heterogeneous vehicular clustering framework for
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作者 Iftikhar AHMAD Rafidah Md NOOR +3 位作者 Zaheed AHMED Umm-e-HABIBA Naveed AKRAM Fausto Pedro GARCIA MARQUEZ 《Frontiers of Information Technology & Electronic Engineering》 SCIE EI CSCD 2021年第9期1247-1259,共13页
Heterogeneous vehicular clustering integrates multiple types of communication networks to work efficiently for various vehicular applications.One popular form of heterogeneous network is the integration of long-term e... Heterogeneous vehicular clustering integrates multiple types of communication networks to work efficiently for various vehicular applications.One popular form of heterogeneous network is the integration of long-term evolution(LTE)and dedicated short-range communication.The heterogeneity of such a network infrastructure and the non-cooperation involved in sharing cost/data are potential problems to solve.A vehicular clustering framework is one solution to these problems,but the framework should be formally verified and validated before being deployed in the real world.To solve these issues,first,we present a het-erogeneous framework,named destination and interest-aware clustering,for vehicular clustering that integrates vehicular ad hoc networks with the LTE network for improving road traffic efficiency.Then,we specify a model system of the proposed framework.The model is formally verified to evaluate its performance at the functional level using a model checking technique.To evaluate the performance of the proposed framework at the micro-level,a heterogeneous simulation environment is created by integrating state-of-the-art tools.The comparison of the simulation results with those of other known approaches shows that our proposed framework performs better. 展开更多
关键词 Vehicular cluster HETEROGENEITY COOPERATION Formal verification System model
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War and Peace in the Persian Gulf:Pre-Westphalian,Westphalian or Post-Westphalian?
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作者 Laszlo Csicsmann Erzsebet N.Rozsa 《Asian Journal of Middle Eastern and Islamic Studies》 2020年第2期216-230,共15页
The international order of territory-based sovereign nation-states(Westphalia)has been in transition towards a so-called‘post-Westphalian order’,but pre-Westphalian structures still prevail.This has been most releva... The international order of territory-based sovereign nation-states(Westphalia)has been in transition towards a so-called‘post-Westphalian order’,but pre-Westphalian structures still prevail.This has been most relevant in the Middle East and North Africa,especially in the Persian Gulf.This coincides with the increasingly delicate(im)balance of power and the changing role of the state in the Persian Gulf,expressed in such narratives as the decline of the state,the United States‘withdrawal’from the region as well as the Iranian-Saudi‘Cold War.’The paper aims at analysing war and peace in this context of the transition of the international order and the regional(im)balance of power,and highlights that war or peace in the Persian Gulf will be the outcome of the competitive multi-polarity of traditional and modern,pre-Westphalian,Westphalian and post-Westphalian actors and factors,where the modalities and methodology of all will play a role. 展开更多
关键词 Westphalian order Gulf studies peace initiative balance of power conflict resolution
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