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岳勇《阿光的艳遇》赏析
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作者 丁勤中 《语文知识》 2006年第1期42-43,共2页
[原文]阿光买了一辆新摩托车.整天骑到街上横冲直撞.大肆炫耀,吓得那些在街上行走的女孩们惊叫不已,好不威风。 这天,阿光又骑着摩托在街上兜风,远远地瞧见一个身着露脐衫、超短裙的美貌女郎在向他招手。他一拐车头,摩托便蹿到... [原文]阿光买了一辆新摩托车.整天骑到街上横冲直撞.大肆炫耀,吓得那些在街上行走的女孩们惊叫不已,好不威风。 这天,阿光又骑着摩托在街上兜风,远远地瞧见一个身着露脐衫、超短裙的美貌女郎在向他招手。他一拐车头,摩托便蹿到了那女郎跟前。“小姐。有什么需要帮忙的吗?”他盯着她雪白的胸脯笑嘻嘻地问。 展开更多
关键词 岳勇 阿光的艳遇》 中学 语文 微型小说 阅读欣赏
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阿光的快乐生活
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《作文新天地(小学版)》 2017年第7期35-35,61,67,71,83,共5页
阿光对小明说:“我每天在早饭前就把我感到最费劲的事情做完了。“小明崇拜地说:“真了不起,是什么事?”阿光:“起床。”妈妈给阿光买了一只鹦鹉。妈妈问:“阿光,你知道这只鹦鹉是公的还是母的吗?”“母的。”阿光毫不犹豫地回答。
关键词 阿光 快乐 生活
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承担不起
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《作文新天地(小学版)》 2018年第10期19-19,共1页
阿光的爷爷被蜘蛛咬了,伤口看起来有点发炎,心情也有点沮丧.于是阿光准备拿点药膏给爷爷涂上.可就在阿光走出房门时,爷爷说:“到了我这个年纪,实在是承担不起蜘蛛侠的责任啊!”
关键词 爷爷 蜘蛛 阿光 心情
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防不胜防
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《作文新天地(小学版)》 2018年第6期44-44,共1页
阿光妈怀疑阿光没做作业就偷看电视,就告诉了阿光爸。阿光爸问:“确定吗?”她摇了摇头,阿光爸说:“没事,看我的!”于是,阿光爸故意在客厅里大喊一句:“天哪,这电视是坏了吗?怎么开了大半天没反应?”阿光立马跑过来说:“不会啊,... 阿光妈怀疑阿光没做作业就偷看电视,就告诉了阿光爸。阿光爸问:“确定吗?”她摇了摇头,阿光爸说:“没事,看我的!”于是,阿光爸故意在客厅里大喊一句:“天哪,这电视是坏了吗?怎么开了大半天没反应?”阿光立马跑过来说:“不会啊,我刚刚还看了!”阿光爸对着阿光妈说道:“确定了,家法伺候!” 展开更多
关键词 看电视 反应 作业 阿光
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Microbial Community Characteristics in the Rhizosphere of Atrazine-contaminated Soil by Dendroremediation of Poplar
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作者 姚斌 刘方 +1 位作者 刘昌勇 韦秀文 《Agricultural Science & Technology》 CAS 2017年第12期2423-2426,2519,共5页
The change of microbial community characteristics in the different rhizo- sphere zones of hybrid poplar (Populusdeltoidsxnigra, DN34) under atrazine stress were investigated by rhizo-boxes and Biolog system in a gre... The change of microbial community characteristics in the different rhizo- sphere zones of hybrid poplar (Populusdeltoidsxnigra, DN34) under atrazine stress were investigated by rhizo-boxes and Biolog system in a greenhouse experiment, with sublimed sulfur and calcium hydroxide as soil pH regulators. Data from the measurement by the Biolog ECO plate demonstrated that the value of average well color development (AWCD) and the carbon source utilization of soil microorganisms in the treatments with pH regulators were promoter than CK during the initial 30 days; while the results from the 90 days indicated that the activity and the carbon source utilization of soil microbes in acid regulator treatment began to fall down, even lower than that of poplar implant treatment, then the alkaline treatment could still stimulate and promote the activity and the carbon source utilization ability of soil microbes. Overall, the activity and community structure of soil microbes in rhizo- sphere zones of atrazine-contaminated soil did not show steady regularity during the phytoremediation process by using hybrid poplars. For the reason that the Biolog E- CO plate, which only had 31 kinds of carbon sources, could not really indicate the detail information about the function diversity of community structure of soil mi- crobes. So it's essential for us to take more sophisticated analysis tools for further study. 展开更多
关键词 POPLAR RHIZOBOX ATRAZINE Microbes Average absorbance Diversity
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Asymmetry of Photoelectron Angular Distributions in Molecules by Intense Attosecond Extreme Ultraviolet Laser Pulses
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作者 于华明 元凯军 孙志刚 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第6期647-652,I0003,共7页
We present photoelectron angular distribution of the aligned molecular ion H2^+ by intense ultrashort attosecond extreme ultraviolet laser pulses from numerical solutions of timedependent Schrodinger equations. Photo... We present photoelectron angular distribution of the aligned molecular ion H2^+ by intense ultrashort attosecond extreme ultraviolet laser pulses from numerical solutions of timedependent Schrodinger equations. Photoionization from a superposition state of the ground 1sσg and the excited 2pσu states with pulses at photon energies above the ionization potential, hω〉Ip, and intensity 10^14 W/cm^2, yields pulse duration dependent asymmetry of photoelectron angular distributions. We attribute the asymmetry to the periodical oscillation of the coherent electron wave packets, resulting from the interference of the two electronic states. For the processes with long pulse durations, such duration dependence is absent and symmetric angular distributions are obtained. 展开更多
关键词 Attosecond photoionization Coherent electron wave packet Photoelectron angular distribution
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Some Suggestions Improving Apollo Lunar Laser Retroreflector Arrays 被引量:1
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作者 LIU Jiyu 《Geo-Spatial Information Science》 2007年第1期1-3,共3页
According to our engineering research on satellite-borne laser retroreflector array, some suggestions are proposed on how to manufacture a new Apollo LLRA that can make us measure one illuminating point and unillumina... According to our engineering research on satellite-borne laser retroreflector array, some suggestions are proposed on how to manufacture a new Apollo LLRA that can make us measure one illuminating point and unilluminating area on the moon's surface. These suggestions are: to control the dihedral angle offset within ± 0.1″; to use the larger aperture of the transparent face of cube corner prisms; to investigate how to separate out Apollo's reflected laser from mixed beam hitting on the LLR system. 展开更多
关键词 lunar laser retroreflector array cube corner prism dihedral angle offset lunar laser ranging
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Retreived bacteria from Noctiluca miliaris (green) bloom of the northeastern Arabian Sea
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作者 BASU Subhajit MATONDKAR SG Prabhu FURTADO Irene 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2013年第1期10-20,共11页
In recent years, seasonal blooms of the dinoflagellate Noctiluca miliaris have appeared in the open-waters of the northern Arabian Sea (NAS). This study provides the first characterization of bacteria from a seasona... In recent years, seasonal blooms of the dinoflagellate Noctiluca miliaris have appeared in the open-waters of the northern Arabian Sea (NAS). This study provides the first characterization of bacteria from a seasonal bloom of green Noctiluca ofNAS (20°N-17°N and 64°E-70°E), during the spring-inter-monsoon cruise ofSagar Sampada 253, in March 2007. Bacterial growth as assessed by most-probable number (MPN) and plate counts, revealed 'variable-physiotypes' over a wide range of salinities (0%-25% w/v NaC1), pH levels (5-8.5), and organic nutrient strengths, in comparison to non-bloom waters. MPN indices of bacteria in surface waters of bloom stations *DWK and *PRB, corresponded to (3.08-4.41)×103 cells/mL at 3.5% NaC1 (w/v), and (2.82-9.49)× 102 cells/mL at 25% (w/v) NaC1 in tryptone-yeast extract broth (TYE). Plate counts were (1.12-4) × 106 CFU/mL at 0% (w/v) NaC1, (1.28-3.9) × 106 CFU/mL at 3.5% (w/v) NaC1, and (0.4- 7)×104 CFU/mL at 25% NaC1 (w/v) on TYE. One-tenth-strength Zobell's gave (0.6-3.74)× 105 CFU/mL at pH 5 to (3.58-7.5)× 105 CFU/mL at pH 8.5. These bacteria were identified to the genera Bacillus, Cellulomonas, Staphylococcus, Planococcus, Dietzia, Diergibacillus, Micrococcus, Sporosarcinae, Leucobacter, and Halomonas. The identity of three strains (GUFBSS253N2, GUFBSS253N30, and GUFBSS253N84) was confirmed through 16S rDNA sequence homology as Bacillus cohnii, Bacillusflexus, and Bacillus cereus. The -2-3-fold higher plate counts of culturable bacteria from the open-waters of the NAS indicate that these bacteria could critically determine the biogeochemical dynamics of the bloom and its milieu. The role of these bacteria in sustaining/terminating the bloom is under evaluation. 展开更多
关键词 northeastern Arabian Sea (NAS) green Noctiluca bloom retrievable bacteria
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The Impact of the Natural Lighting and Ventilation in Therapeutic Buildings: An Environmental Field Study in Makkah, Saudi Arabia
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作者 Alanoud Abdulaziz Alansari Kazuhiro Hirao 《Journal of Civil Engineering and Architecture》 2017年第2期194-198,共5页
"Paradise Garden" concept has given rise to the application of several spiritual and aesthetic meaning that helped raise the efficiency of the therapeutic environment. The hypothesis revolves around the idea that th... "Paradise Garden" concept has given rise to the application of several spiritual and aesthetic meaning that helped raise the efficiency of the therapeutic environment. The hypothesis revolves around the idea that the technological development increased the interest in the functional side rather than the aesthetic side in the current therapeutic buildings. This had a negative effect on the efficiency of the functional environment and thus exceeded the negative impact on the satisfaction and comfort of the building users. This hypothesis has been tested through two types of studies: first, analytical study of four hospitals by analyzing the horizontal projections to measure the effects of the natural lighting and ventilation; second, questionnaires were distributed to both the patients and the staff in the therapeutic buildings to measure the therapeutic environment efficiency and the extent of satisfaction of users of the building. It was concluded that the natural lighting and ventilation drive up healing rate in the therapeutic environment. The correctness of this idea is revealed by the conclusion that the technological advances in the medical field helped to raise the level of functional performance and thus it replaced a large part of the role of the natural lighting and ventilation. 展开更多
关键词 Therapeutic buildings paradise garden Bimaristan.
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Beyond Tourist Gaze in Select Odia Travel Writings of Gobinda Das, Golakbihari Dhal and Pratibha Ray
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作者 Supriya Subhadarsini Sahoo 《Journal of Literature and Art Studies》 2018年第6期969-976,共8页
This paper focuses the question: What does it mean to be a traveller rather than a tourist? The term “tourism” ismostlyused in impersonal commercial language but “travel” often implies the personal, picaresque s... This paper focuses the question: What does it mean to be a traveller rather than a tourist? The term “tourism” ismostlyused in impersonal commercial language but “travel” often implies the personal, picaresque style of travel writing. The travellerbeing the hero of the text and the tourist as an unfortunate by-product of globalisation highlight the formation of the important binary opposites through the identity/difference logic.Travel writers deprecate the behaviour of tourists and go for a more authentic way to engage with cultural contrastfor a more concrete example of otherness. The primary texts taken for this study are the select Odia travel writers: GobindaDas’sDese Dese (In Countries), GolakbihariDhal’sLondon Chithi (Letter From London), and Pratibha Ray’s Swapnara Alaska (Dreamy Alaska) and Africa NayikaNilanadi (Africa’s Heroine the River Nile). 展开更多
关键词 tourist gaze travel writing travelling gaze SELFHOOD OTHERING
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Effects of Zn/P ratio on structures and properties of zinc-iron phosphate glasses
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作者 李秀英 杨华明 任宇曦 《Journal of Central South University》 SCIE EI CAS 2013年第1期44-49,共6页
Effects of Zn/P ratio on the structures and properties of glasses with the general composition of (80-x)ZnO-20Fe2O3-xP2O5 (x=40, 45, 50, 55, 60) (molar fraction, %) were investigated. Glass structure was measure... Effects of Zn/P ratio on the structures and properties of glasses with the general composition of (80-x)ZnO-20Fe2O3-xP2O5 (x=40, 45, 50, 55, 60) (molar fraction, %) were investigated. Glass structure was measured by infrared absorption spectrum. Glass density (/9) was measured by the Archimedes method. Coefficients of thermal expansion (a) and characterization temperature were obtained by a dilatometer. Water durability of each glass was estimated from the dissolution rate (DR)in water at 90 ℃ for 24 h. With increasing Zn/P ratio, water durability of zinc-iron phosphate glasses increases dramatically without large increase in the characterization temperature. (80-x)ZnO-20Fe2O3-xP2O5 glasses with 0.3≤Zn/P≤0.5 are suit for low-to-mid temperature sealing application for substrates with a〈8.0× 10^-6℃^-1. 展开更多
关键词 zinc-iron phosphate glass SEALING structure water durability characterization temperature
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Spatiotemporal Dynamics of Forest and Mountain Formations in Auras Area, Algeria
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作者 Yassine Beghami Mahdi Kalla +1 位作者 Michel Thinon Hassen Benmessaoud 《Journal of Life Sciences》 2012年第6期663-669,共7页
Contrary to the countries of northern coast, the forest formations on Southern and East coast of the Mediterranean are in regression. With the combined action of the ax, fire and pasture, these ecosystems are subjecte... Contrary to the countries of northern coast, the forest formations on Southern and East coast of the Mediterranean are in regression. With the combined action of the ax, fire and pasture, these ecosystems are subjected to a pressure of permanent degradation. Indeed, the degradation of the forest ecosystems represents one of the most important causes of reduction and erosion of the biodiversity in the world. The massif of Aur6s is located in the North-East of Algeria. The analysis of the spatiotemporal dynamics of this vulnerable vegetation is not approached yet. This study proposes a focus on the analysis of the dynamics of this vegetation and to study the factors of its degradation. For that, a methodological approach of diachronic follow-up between two dates was adopted by using any kind of old information sources (archives, aerial photographs, topographic maps) and recent (Images satellite of American Landsat and data of land). The results reveal a degradation of vegetable cover thus expressing a very thorough reduction of the formations forest replaced by herbaceous formations very sensitive and threatened by the overgrazing. 展开更多
关键词 Aures diachronic analysis cedar forest formations remote sensing
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Hybrid PV/Wind/Diesel Based Distributed Generation for an Off-Grid Rural Village in Afghanistan
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作者 Gul Ahmad Ludin Hidehito Matayoshi +2 位作者 Mir Sayed Shah Danish Atsushi Yona Tomonobu Senjyu 《Journal of Energy and Power Engineering》 2017年第2期85-94,共10页
Afghanistan has a tremendous resource potential of renewable energy especially solar and the wind. Therefore, utilization of these resources has a special rule for the remote areas where access to the electrical grid ... Afghanistan has a tremendous resource potential of renewable energy especially solar and the wind. Therefore, utilization of these resources has a special rule for the remote areas where access to the electrical grid or secure power supply is a dream for most of the people. This paper presents a feasibility and usefulness of hybrid power generation based on PV/wind/diesel generator for an off-grid rural village that feeds the load at a rate of average 7.9 kWh/day with 1.32 kW peak load. GsT (geospatial toolkit) is used to obtain the solar and wind data of the site. Windographer software is used to analyze the wind resource data of the site. HOMER Pro software package is used to select the suitable and reliable hybrid generation system and calculate the optimal capacities and costs of the components. Through the study, it is found that this state of the art adaptation could provide vast opportunities for off-grid rural communities such as in Afghanistan where enough high penetration of renewable energy is available. 展开更多
关键词 Rural village electrification hybrid power generation solar WIND diesel generator.
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Evaluating Economic and Environmental Benefits of Integrating Solar Photovoltaics within Future Residential Buildings in Saudi Arabia 被引量:1
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作者 H.M. Taleb Y.M. Al-Saleh 《Journal of Energy and Power Engineering》 2010年第1期18-25,共8页
Renewable energy options, including solar power, are becoming increasingly viable alternatives to conventional sources of energy, such as oil, coal and natural gas. Solar Photovoltaic (PV) technology is one type of ... Renewable energy options, including solar power, are becoming increasingly viable alternatives to conventional sources of energy, such as oil, coal and natural gas. Solar Photovoltaic (PV) technology is one type of solar energy technologies that has recently received substantial attention because it offers the possibility of providing clean power sources for buildings. The aim of this paper is to examine the economic viability of using solar PV within future residential buildings in the oil-rich Saudi Arabia. Strictly speaking, the prospects of using the PV in order to provide 10% of the electricity to be consumed in the houses, which are going to be built in Sandi Arabia over the period 2010-2025, are examined. The study reveals that significant economic and environmental benefits could be realized as a result of such an endeavor. 展开更多
关键词 Renewable energy solar photovoltaics Sandi Arabia residential buildings feasibility study.
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Detailed Study on Establishing a PV Power Plant to Generate Electricity in Saudi Arabia
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作者 E.A. Al-Ammar 《Journal of Energy and Power Engineering》 2011年第2期155-163,共9页
Photvoltiacs (PV) power plants have beell built all over the world, and are successfully proven as one of the important substitutes of alternative energy sources. In the Kingdom of Saudi Arabia, the electricity dema... Photvoltiacs (PV) power plants have beell built all over the world, and are successfully proven as one of the important substitutes of alternative energy sources. In the Kingdom of Saudi Arabia, the electricity demand will double in the next 15 years, dramatically increasing fuel consumption. To meet this huge load growth, there has been some series of movements to find out solutions. This research aims at studying the feasibility of design and construction of a solar power plant using photovoltaic cells in Saudi Arabia from the geographic, economic and technical perspectives. It's concluded that PV power is competitive with the conventional capacity required to meet "peak" power demand and represents an opportunity for reducing fuel consumption in Saudi Arabia. 展开更多
关键词 FEASIBILITY Saudi Arabia STUDY PV
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Salt's Effect on Anatomy and Deformity of Pistacia vera Nut
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作者 F. Zarinkamar E. Farjady 《Journal of Agricultural Science and Technology(A)》 2011年第4X期599-607,共9页
This study attempts to examine the effects of salinity on leaf, stem, and nut of Pistacia vera (Ohady and Kaleh Ghochi cultivars) in order to characterize their anatomical structures with electron and light microsco... This study attempts to examine the effects of salinity on leaf, stem, and nut of Pistacia vera (Ohady and Kaleh Ghochi cultivars) in order to characterize their anatomical structures with electron and light microscopy. A comparative study of the anatomy indicates a difference between the density of simple and glandular trichomes in leaf surface, deposit of wax, the thickness of leaf, the length of epidermal cells, palisade parenchyma cells, crystals in mesophyll, and the manner of compatibility to salinity. The results obtained in this research demonstrate that compatibility of Ohady cultivar is higher than Kaleh Ghochi and the degree of mechanical wounding depends on their development stages. In addition to results of previous studies which considered crop load as the main cause of fruit deformity. The present study indicates that, in spite of some reduction in total production of a tree, salinity decreases fruit deformity and to a high extent prevents the production of deformed fruit. Indeed, a remarkable reduction in production of deformed fruit will be yielded by selecting pistachio varieties which are resistant to salinity. Moreover, salinity increases the resistance of nuts to mechanical wounding. The results of this study suggest that in EC = 7.6, 12.6 deformity of nut is not related to crop load. 展开更多
关键词 Pistachio (Pistacia vera L.) SALINITY ANATOMY deformity of nuts mechanical wounding.
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Establishment of an HPLC method for the analysis of biapenem and its impurities 被引量:1
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作者 王楠 李春凤 +1 位作者 张斗胜 胡昌勤 《Journal of Chinese Pharmaceutical Sciences》 CAS 2011年第2X期171-180,共10页
An HPLC method for routine quality control of biapenem was established.A Dikma Diamonsil C_(18) column(250mm×4.6 mm,5μm) was used with diode array detection and single wavelength detection at 220 nm.The mobile p... An HPLC method for routine quality control of biapenem was established.A Dikma Diamonsil C_(18) column(250mm×4.6 mm,5μm) was used with diode array detection and single wavelength detection at 220 nm.The mobile phase was consisted of acetonitrile-0.1%triethylamine water(1:99,v/v).The liner range for biapenem quantification was 0.05-10.0 mg/mL(r^2= 0.999). The LOD and LOQ of impurity were 4.8 ng(S/N = 3) and 18.5 ng(S/N = 10),respectively.Intra-day RSD of main impurity and total impurity were 1.84%and 3.37%(n = 3);inter-day RSD of main impurity and total impurity were 4.84%and 7.58% (n = 9).The test solution was stable when stored at 4℃for 6 h.The impurity peaks of biapenem can be identified by chromatographic spectral correlation analysis using high-performance liquid chromatography-diode array detection data from the quality control method by calculating correlation coefficients without reference standards.Two hydrolysis degradation products with relative retention times(RRTs) of 0.528 and 0.743,two dimers with RRTs of 1.062 and 2.817 were identified in the quality control chromatogram.It provides a new way to identify impurity peaks by the routine HPLC-UV method. 展开更多
关键词 BIAPENEM HPLC-DAD Two-dimensional chromatographic spectral correlative map Identification IMPURITIES
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Manufacturer identification and storage time determination of “Dong'e Ejiao” using near infrared spectroscopy and chemometrics 被引量:5
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作者 Wen-long LI Hai-fan HAN +2 位作者 Lu ZHANG Yan ZHANG Hai-bin QU 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2016年第5期382-390,共9页
We have developed a set of chemometric methods to address two critical issues in quality control of a precious traditional Chinese medicine (TCM), Dong'e Ejiao (DEE J). Based on near infrared (NIR) spectra of m... We have developed a set of chemometric methods to address two critical issues in quality control of a precious traditional Chinese medicine (TCM), Dong'e Ejiao (DEE J). Based on near infrared (NIR) spectra of multiple samples, the genuine manufacturer of DEE J, e.g. Dong'e Ejiao Co., Ltd., was accurately identified among 21 suppliers by the fingerprint method using Hotelling T2, distance to Model X (DModX), and similarity match value (SMV) as dis- criminate criteria. Soft independent modeling of the class analogy algorithm led to a misjudgment ratio of 6.2%, suggesting that the fingerprint method is more suitable for manufacturer identification. For another important feature related to clinical efficacy of DEE J, storage time, the partial least squares-discriminant analysis (PLS-DA) method was applied with a satisfactory misjudgment ratio (15.6%) and individual prediction error around 1 year. Our results demonstrate that NIR spectra comprehensively reflect the essential quality information of DEE J, and with the aid of proper chemometric algorithms, it is able to identify genuine manufacturer and determine accurate storage time. The overall results indicate the promising potential of NIR spectroscopy as an effective quality control tool for DEEJ and other precious TCM products. 展开更多
关键词 Dong'e Ejiao Near infrared spectroscopy Manufacturer identification Storage time identification Quality control
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The effects of asymmetric potential vorticity forcing on the instability of South Asia High and Indian summer monsoon onset 被引量:5
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作者 ZHANG YaNi WU GuoXiong +1 位作者 LIU YiMin GUAN Yue 《Science China Earth Sciences》 SCIE EI CAS 2014年第2期337-350,共14页
Based on the theory of potential vorticity(PV),the unstable development of the South Asia High(SAH)due to diabatic heating and its impacts on the Indian Summer Monsoon(ISM)onset are studied via a case diagnosis of 199... Based on the theory of potential vorticity(PV),the unstable development of the South Asia High(SAH)due to diabatic heating and its impacts on the Indian Summer Monsoon(ISM)onset are studied via a case diagnosis of 1998.The Indian Summer Monsoon onset in 1998 is related to the rapidly strengthening and northward moving of a tropical cyclone originally located in the south of Arabian Sea.It is demonstrated that the rapid enhancement of the cyclone is a consequence of a baroclinic development characterized by the phase-lock of high PV systems in the upper and lower troposphere.Both the intensification of the SAH and the development of the zonal asymmetric PV forcing are forced by the rapidly increasing latent heat released from the heavy rainfall in East Asia and South East Asia after the onsets of the Bay of Bengal(BOB)monsoon and the South China Sea(SCS)monsoon.High PV moves southwards along the intensified northerlies on the eastern side of the SAH and travels westwards on its south side,which can reach its northwest.Such a series of high PV eddies are transported to the west of the SAH continuously,which is the main source of PV anomalies in the upper troposphere over the Arabian Sea from late spring to early summer.A cyclonic curvature on the southwest of the SAH associated with increasing divergence,which forms a strong upper tropospheric pumping,is generated by the anomalous positive PV over the Arabian Sea on 355 K.The cyclone in the lower troposphere moves northwards from low latitudes of the Arabian Sea,and the upper-layer high PV extends downwards and southwards.Baroclinic development thus occurs and the tropical low-pressure system develops into an explosive vortex of the ISM,which leads to the onset of the ISM.In addition,evolution of subtropical anticyclone over the Arabian Peninsula is another important factor contributing to the onset of the ISM.Before the onset,the surface sensible heating on the Arabian Peninsula is very strong.Consequently the subtropical anticyclone which dominated the Arabian Sea in spring retreats westwards to the Arabian Peninsula and intensifies rapidly.The zonal asymmetric PV forcing develops gradually with high PV eddies moving southwards along northerlies on the eastern side of the anticyclone,and a high PV trough is formed in the middle troposphere over the Arabian Sea,which is favorable to the explosive barotropic development of the tropical cyclone into the vortex.Results from this study demonstrate that the ISM onset,which is different from the BOB and the SCS monsoon onset,is a special dynamical as well as thermodynamic process occurring under the condition of fully coupling of the upper,middle,and lower tropospheric circulations. 展开更多
关键词 potential vorticity South Asian High diabatic heating zonal asymmetric instability summer monsoon onset
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Broadband isolated attosecond pulse generation in a two-color laser field combined with an orthogonally polarized laser pulse 被引量:2
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作者 DU HongChuan WANG XiaoShan HU BiTao 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2012年第1期1-6,共6页
We present a method to generate broadband isolated attosecond pulses. Using a two-color laser field, which is synthesized by a mid-infrared (12.5 fs, 2000 nm) and a weaker (12 fs, 800 nm) pulse in the x direction,... We present a method to generate broadband isolated attosecond pulses. Using a two-color laser field, which is synthesized by a mid-infrared (12.5 fs, 2000 nm) and a weaker (12 fs, 800 nm) pulse in the x direction, a modulated supercontinuum from 290 to 430 eV is obtainable. By properly adding a second-harmonic control field of the driving pulse in the y direction, the short quantum path is well selected and a smooth supercontinuum from 290 to 440 eV is generated. The bandwidth of the supercontinuum can be controlled by adjusting the electric field of the control pulse in the x direction. When the electric field increases to 0.051 a.u., a smooth supercontinuum from 295 to 520 eV is obtained. Using this method we expect that isolated 63-as attosecond pulses with tunable central wavelengths are straightforwardly obtained.We present a method to generate broadband isolated attosecond pulses. Using a two-color laser field, which is synthesized by a mid-infrared (12.5 fs, 2000 nm) and a weaker (12 fs, 800 nm) pulse in the x direction, a modulated supercontinuum from 290 to 430 eV is obtainable. By properly adding a second-harmonic control field of the driving pulse in the y direction, the short quantum path is well selected and a smooth supercontinuum from 290 to 440 eV is generated. The bandwidth of the supercontinuum can be controlled by adjusting the electric field of the control pulse in the x direction. When the electric field increases to 0.051 a.u., a smooth supercontinuum from 295 to 520 eV is obtained. Using this method we expect that isolated 63-as attosecond pulses with tunable central wavelengths are straightforwardly obtained. 展开更多
关键词 HHG SUPERCONTINUUM attosecond pulses
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