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中红外光谱在食品掺假检测中的应用研究 被引量:1
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作者 赵琦 王丰好 《食品安全导刊》 2021年第3期162-162,共1页
本文首先阐述了中红外光谱在食品掺假检测中的引用优势,并从食用油、肉食品、糖类物质三个方面展开具体应用分析,以此规避食品掺假问题,旨在借助具体应用实例深化对中红外光谱技术的认知。
关键词 中外红光谱 食品掺假检测 食用油 肉制品 糖类
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有机化学多步合成实验探索 被引量:1
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作者 叶孝勇 《黔南民族师范学院学报》 2003年第3期29-30,共2页
设计和指导学生做了由正丁醇开始经四步合成 2—甲基— 2、3—二溴已烷的合成实验 ,应用折射仪和红外光谱仪对中间产物的折光率和结构进行检测和记录 。
关键词 折光率 中外红光谱 亲核取代 亲核加成
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Rapidly determining kinematic viscosity of aviation lubricating oil 50-1-4Φ by mid-infrared spectrometry
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作者 宗营 姜旭峰 +1 位作者 孙静 校云鹏 《Journal of Measurement Science and Instrumentation》 CAS 2014年第3期79-82,共4页
This paper analyzed 11 lubricating oil 50-1-4Ф samples of different base oil content (standard oil) and 28 used oil samples by Fourier transform mid-infrared spectrometer (FTIR). First, the absorption peak of 1 4... This paper analyzed 11 lubricating oil 50-1-4Ф samples of different base oil content (standard oil) and 28 used oil samples by Fourier transform mid-infrared spectrometer (FTIR). First, the absorption peak of 1 465 cm 1 was selected as the characteristic peak for determining their kinematic viscosities. And then correlation of the kinematic viscosity and the absorbance at characteristic peaks of corresponding infrared spectrum of standard oil and used oil samples was analyzed, re- spectively, and two regression equations were proposed. Finally, the regression equation of standard oil was corrected through other 20 new oil samples. The results show that determining kinematic viscosity of new lubricating oil 50-1-4Ф and the used one by FTIR is feasible and reliable. 展开更多
关键词 mid-infrared spectrum aviation lubricating oil kinematic viscosity
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Rapidly determining fuel pollution level of aviation lubricating oil 50-1-4Φby mid-infrared spectrometry
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作者 宗营 姜旭峰 +1 位作者 岳聪伟 孙静 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2015年第2期190-192,共3页
A series of aviation lubrication oil 50-1-4φ samples were prepared with different RP-3 content, and then these sam- ples were analyzed by Fourier transform mid-infrared spectrometer (FTIR). The infrared region of ... A series of aviation lubrication oil 50-1-4φ samples were prepared with different RP-3 content, and then these sam- ples were analyzed by Fourier transform mid-infrared spectrometer (FTIR). The infrared region of 805--755 cm-1 was selected as quantitative area for determining fuel pollution level of aviation lubrication oil. Finally, correlation of the testing peak area and the fuel pollution level of corresponding samples were analyzed, and the regression equation was proposed. The results show that determining jet fuel pollution level of aviation lubricating oil by FTIR is feasible and reliable. 展开更多
关键词 mid-infrared spectrum aviation lubricating oil fuel pollution level
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Selective reduction of carbon dioxide to carbon monoxide over Au/CeO_2 catalyst and identification of reaction intermediate 被引量:1
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作者 朱晓兵 曲新 +4 位作者 李小松 刘景林 刘剑豪 朱斌 石川 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第12期2053-2058,共6页
CO2 selective reduction to CO with H2 over a CeO2-supported nano-Au catalyst at atmospheric pres- sure was investigated. A high CO2 conversion, approaching the thermodynamic equilibrium value, and nearly 100% CO selec... CO2 selective reduction to CO with H2 over a CeO2-supported nano-Au catalyst at atmospheric pres- sure was investigated. A high CO2 conversion, approaching the thermodynamic equilibrium value, and nearly 100% CO selectivity were obtained. The surface formate intermediates generated during the reverse water-gas shift reaction at 400 ℃ were identified using in situ diffuse-reflectance infra- red Fourier-transform spectroscopy. The formate consumption to give CO and H20, determined using mass spectrometry, indicated that the reaction proceeded via an associative formate mecha- nism; this contributes to the high Au/CeO2 catalytic activity at low temperatures. 展开更多
关键词 CO2 reductionAu/CeO2 catalystCarbon monoxide Formate intermediate In situ DRIFT spectroscopy
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Infrared-Vacuum Ultraviolet Spectroscopic and Theoretical Study of Neutral Trimethylamine Dimer
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作者 张冰冰 孔祥涛 +6 位作者 蒋述康 赵志 谢华 郝策 戴东旭 杨学明 江凌 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2017年第6期691-695,I0002,共6页
Infrared-vacuum ultraviolet (IR-VUV) spectra of neutral trimethylamine dimer were mea- sured in the 2500-3800 cm-1 region. Quantum chemical calculations were performed to identify the structure of the low-lying isom... Infrared-vacuum ultraviolet (IR-VUV) spectra of neutral trimethylamine dimer were mea- sured in the 2500-3800 cm-1 region. Quantum chemical calculations were performed to identify the structure of the low-lying isomers and to assign the observed spectral features. The bands at 2975 and 2949 cm-1 were assigned to the antisymmetric C-H stretching and the band at 2823 cm-1 to the symmetric C-H stretching, respectively. The 2739 cm-1 band was due to the CH3 bending overtone, which disappeared at low IR laser power of 1 mJ/mm2. The extra band at 2773 cm-1 could be due to Fermi resonance behavior of the light isotopologue, these are often close in energy and can strongly mix through cubic terms in the potential function. Experimental and theoretical results indicate the likely coexistence of multiple structures. The peak widths of IR spectra of neutral trimethylamine dimer are not significantly affected by the structural transformation, allowing the stretching modes to be well resolved. 展开更多
关键词 Infrared-vacuum ultraviolet Neutral cluster TRIMETHYLAMINE Quantum chemical calculation
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Research on Determination of Nitrogen Content in Petroleum Using Mid-infrared Spectroscopy 被引量:2
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作者 Li Jingyan Chu Xiaoli +1 位作者 Tian Songbai Lu Wanzhen (SINOPEC Research Institute of Petroleum Processing, Beijing 100083) 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2011年第4期1-7,共7页
Nitrogen content is an important parameter for petroleum refining processes. The combined use of mid-infrared attenuated total reflection spectroscopy and multivariate calibration allows accurate determination of nitr... Nitrogen content is an important parameter for petroleum refining processes. The combined use of mid-infrared attenuated total reflection spectroscopy and multivariate calibration allows accurate determination of nitrogen content in petroleum and its products. The calibration models of nitrogen content in crude oils have been established by partial least squares (PLS) method. The results predicted by this method were very close to those determined by standard methods. Compared with standard methods, this method is provided with advantages such as high-speed, simplicity and good-repeat- ability without any needs for pretreatment. 展开更多
关键词 PETROLEUM mid-infrared spectroscopy partial least square NITROGEN
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Infrared Spectroscopy of Neutral Clusters Based on a Vacuum Ultraviolet Free Electron Laseri 被引量:1
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作者 Gang Li Chong Wang +4 位作者 Hui-jun Zheng Tian-tong Wang Hua Xie Xue-ming Yang Ling Jiang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2021年第1期51-60,I0011,共11页
Spectroscopic characterization of clusters is crucial to understanding the structures and reaction mechanisms at the microscopic level,but it has been proven to be a grand challenge for neutral clusters because the ab... Spectroscopic characterization of clusters is crucial to understanding the structures and reaction mechanisms at the microscopic level,but it has been proven to be a grand challenge for neutral clusters because the absence of a charge makes it di伍cult for the size selection and detection.Infrared(IR)spectroscopy based on threshold photoionization using a tunable vacuum ultraviolet free electron laser(VUV-FEL)has recently been developed in the lab.The IR-VUV depletion and IR+VUV enhancement spectroscopic techniques open new avenues for size-selected IR spectroscopies of a large variety of neutral clusters without confinement(i.e.,an ultraviolet chromophore,a messenger tag,or a host matrix).The spectroscopic principles have been demonstrated by investigations of some neutral water clusters and some metal carbonyls.Here,the spectroscopic principles and their applications for neutral clusters are reviewed. 展开更多
关键词 CLUSTERS Infrared spectroscopy Vacuum ultraviolet free electron laser STRUCTURES Reaction mechanisms
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Changes in organic structure and mineral phases transformation of coal during heat treatment on laboratory scale 被引量:8
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作者 Vivek Mishra Mamta Sharma +1 位作者 Sanchita Chakravarty Amit Banerjee 《International Journal of Coal Science & Technology》 EI 2016年第4期418-428,共11页
Structural changes due to coalification and oxidation influence the coal quality, geochemically and petrologically. Understanding of the coal structures helps to predict the behaviour of coal at various processes. The... Structural changes due to coalification and oxidation influence the coal quality, geochemically and petrologically. Understanding of the coal structures helps to predict the behaviour of coal at various processes. The objective of this paper is to study the changes in organic structure and mineral phase transformation during combustion. Different density fractions were generated and then heated at different temperatures from 200 to 1000 ℃. Petrography, Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) were carried out on all the density fractions aimed to accomplish this objective. Here, through petrography, it was observed that the vitrinite and liptinite macerals disappear at higher temperature while porous inertinite is seen. The inertinite structure is exposed which is assumed by the presence of -OH and C-O-C stretches with the aromatic nucleus (CH) and three to four adjacent H from FTIR spectra. Moreover, it can be concluded that aliphatic groups get collapsed at high temperature. In case of inorganic matter, through XRD and FTIR, it is also revealed that with increasing temperature, clay minerals converted into elemental oxides. Hence, this study is suggesting that the structures of coal are altered by the degree of contact metamorphism. 展开更多
关键词 COAL Heat treatment Oxidation PETROGRAPHY FTIR XRD
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O2-Oxidation of Cyanomethylene Radical:Infrared Identification of Criegee Intermediates syn-and anti-NCC(H)OO 被引量:1
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作者 Bo Lu Yuan-yuan Qin +3 位作者 Chao Song Wei-yu Qian Li-na Wang Xiao-qing Zeng 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2020年第2期151-159,I0002,I0018-I0038,共31页
Cyanomethylene radical(HCCN)is an important intermediate in the nitrile chemistry in both the earth’s and the Titan’s atmosphere.Despite that the mechanism for the oxidation of HCCN has been already computationally ... Cyanomethylene radical(HCCN)is an important intermediate in the nitrile chemistry in both the earth’s and the Titan’s atmosphere.Despite that the mechanism for the oxidation of HCCN has been already computationally explored,the key Criegee intermediate,NCC(H)OO,remains unobserved yet.By photolyzing mixtures(1:50:1000)of either HC(N2)CN/O2/N2(266 nm)or HCCNCO/O2/N2(193 nm)at 15.0 K,the elusive carbonyl oxides NCC(H)OO,in syn-and anti-conformations,have been generated and characterized with IR spectroscopy.The spectroscopic identification is supported by ^18O-labeling experiments and the quantum chemical calculations at the BP86/6-311++G(3df,3pd)level.Upon subsequent UV-light irradiation,both conformers of NCC(H)OO further react with O2 and yield NCC(O)H and O3,whereas,the dioxirane isomer HC(O2)CN,which is lower than syn-NCC(H)OO by 23.7 kcal/mol at the CCSD(T)-F12a/aug-cc-pVTZ//BP86/6-311++G(3df,3pd)level,was not observed experimentally. 展开更多
关键词 Methylene radicals Criegee intermediates Oxidation PHOTOCHEMISTRY IR spectroscope
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Geochemical characteristics and mode of occurrence of trace elements in coal at West Bokaro coalfield 被引量:5
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作者 Sk. Md. Equeenuddin Subhasish Tripathy +1 位作者 Prafuila Kumar Sahoo Amit Ranjan 《International Journal of Coal Science & Technology》 EI 2016年第4期399-406,共8页
The mineralogy and trace element contents in coals from the West Bokaro coalfield, which is the one of the biggest Gondwana coalfields of India, were studied to delineate enrichment of trace elements and their modes o... The mineralogy and trace element contents in coals from the West Bokaro coalfield, which is the one of the biggest Gondwana coalfields of India, were studied to delineate enrichment of trace elements and their modes of occur- rence. Elemental concentrations with reference to their crustal abundances indicated that coals are relatively enriched in As (4.4-15.5 mg/kg), Cd (0.3-3.0 mg/kg), Cu (28.0-68.1 mg/kg) and V (46.6-178.0 mg/kg); depleted in Co (10.8-28.4 mg/ kg), Mn (7.6-483.4 mg/kg), Ni (13.0-31.6 mg/kg), Cr (14.2-85.5 mg/kg) and Zn (5.25-70.4 mg/kg). The concentration of As, Cd, Co, Cu and V were higher than the average values of world and Indian coals. Mineralogical study carried out by X-ray diffraction shows that quartz and kaolinite occur as dominant mineral phases in this coal. Fourier transform infrared spectroscopy pattern suggests organic structures primarily containing aromatic nuclei, aliphatic side chain and some oxygen containing groups. The modes of occurrence of trace elements present in these coals have been determined through statistical approach. Both Cu and Cr are more closely associated with mineral matter, whereas Co is dominantly present with its organic form. The concentrations of Cd, Mn, Ni, Zn, As and V have apparently occur in both organic and inorganic constituents. This study would be helpful to assess the potential environmental impacts during mining and combustion of this coal. 展开更多
关键词 MINERALOGY Organic group Trace elements COAL West Bokaro
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Carob Origin Classification by FTIR Spectroscopy and Chemometrics
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作者 Fatiha Alabdi Naima Elharfi Abdessamad Balouki Fouzia Kzaiber Abdelkhalek Oussama 《Journal of Chemistry and Chemical Engineering》 2011年第11期1020-1029,共10页
The goal of this study was to use Fourier transform mid-infrared (FTIR) spectroscopy for discrimination of samples of pods and seeds of carob from three Moroccan regions. The origin of samples Pods and seeds of caro... The goal of this study was to use Fourier transform mid-infrared (FTIR) spectroscopy for discrimination of samples of pods and seeds of carob from three Moroccan regions. The origin of samples Pods and seeds of carob could be distinguished from their IR spectra and this measurement was used for discriminate analysis. A multivariate analysis procedure based on the combined use of Hierarchical Cluster Aanalysis (HCA) and Partial Least Squares-Discriminant Analysis (PLS-DA) was tested and provided good classification results. Three distinctive clusters were recognised, related to the three Moroccan regions. Afterwards, PLS-DA was used for the discrimination and classification of the origin of the various Pods and seeds of carob samples. The results demonstrated that the combined use of FTIR and chemometric analysis (cluster analysis and discrimination by PLS- DA) can be used to rapidly and simply determine the origin of carob pulpe samples. 展开更多
关键词 FTIR discriminant analysis CHEMOMETRICS pods of carob seeds of carob origin classification cluster analysis PLS-DA.
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Near and Mid Infrared Spectroscopy to Detect Malolactic Biotransformation of Oenococcus oeni in a Wine-Model
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作者 Vigentini Ileana Grassi Silvia Sinelli Nicoletta Di Egidio Valentina Picozzi Claudia Foschino Roberto Casiraghi Ernestina 《Journal of Agricultural Science and Technology(A)》 2014年第6期475-486,共12页
The aim of this work was to verify the potential of infrared (IR) spectroscopy in near and mid regions to detect the beginning of the malolactic fermentation (MLF) occurring in a model-wine and the further cells a... The aim of this work was to verify the potential of infrared (IR) spectroscopy in near and mid regions to detect the beginning of the malolactic fermentation (MLF) occurring in a model-wine and the further cells autolysis. MLF in wine is a secondary biotransformation due to lactic acid bacteria that usually occurs spontaneou,;ly or after starter inoculation at the end of alcoholic fermentation. Nowadays, it is desirable to supply winemakers with a new rapid and non-destructive approach to monitor MLF progress and 1R spectroscopy technology appears to be suitable for this purpose. The transformation of L-malic acid into L-lactic acid was carried out by inoculating a synthetic wine with an Oenococcus oeni culture and it was monitored through microbiological and chemical methods. At the same time, Fourier transform near infrared (FT-NIR) spectral data, in diffusive transflection mode using an optic probe, and FT-IR spectra, using an germanium crystal attenuated total reflectance (ATR) cell, were collected. Principal component analysis of the spectra was able to identify absorption bands related to the key molecular modifications that took place during the L-malic acid transformation. Thus, the samples were discriminated according to the fermentation phase. Although this study is a preliminary approach, results confirm that near infrared (NIR) and mid infrared (MIR) spectroscopy could be successfully applied to detect the start of MLF and the autolysis of the lactic acid bacteria (LAB) cells. 展开更多
关键词 Malolactic fermentation WINE FT-IR FT-NIR Oenococcus oeni.
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Eutectic effect during mesophase formation in co-carbonization of ethylene tar pitch and polystyrene 被引量:2
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作者 Cheng Xianglin Song Shulei 《International Journal of Mining Science and Technology》 2012年第2期183-186,共4页
Ethylene tar pitch was co-carbonized with waste polystyrene to prepare mesophase pitch. The character- istics of mesophase pitches were examined using polarized light optical microscopy, apparent viscome- try, Fourier... Ethylene tar pitch was co-carbonized with waste polystyrene to prepare mesophase pitch. The character- istics of mesophase pitches were examined using polarized light optical microscopy, apparent viscome- try, Fourier transform infrared spectrometry, IH nuclear magnetic resonance spectrometry, and X-ray diffractometry. The properties of the mesophase pitch were greatly improved because of the eutectic effect. The soluble content increased from 5% to 56%, the mesophase itself increased from 32% to 100%, and the optical texture was changed from a coarse mosaic into a flow domain after the waste polystyrene was added to the ethylene tar pitch. The apparent viscosity showed that the mesophase pitch changed from thixotropic to Newtonian suggesting improved rheological behavior during co-carbonization)The increased number of alkyl groups, which are mainly methylene groups, altered the molecular structure of the mesophase pitch in a way that resulted in the eutectic effect. 展开更多
关键词 Eutectic effectEthylene tar pitchWaste polystyreneCo-carbonizationMesophase pitch
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Classification of Barley according to Harvest Year and Species by Using Mid-infrared Spectroscopy and Multivariate Analysis
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作者 Ajib Budour Fournier Frantz +2 位作者 Boivin Patrick Schmitt Marc Fick Michel 《Journal of Food Science and Engineering》 2014年第1期36-54,共19页
In order to monitor malt quality in the malting industry, despite yearly variations in the barley quality, 394 barley samples were analysed using conventional (moisture, protein and B-glucan content) and mid-infrare... In order to monitor malt quality in the malting industry, despite yearly variations in the barley quality, 394 barley samples were analysed using conventional (moisture, protein and B-glucan content) and mid-infrared Fourier transform spectroscopy FT-IR. The experimental dataset included barley from three harvest years, two barley species, 77 barley varieties, and two-row and six-row barley, from 16 cultivation sites. For each sample, the malt quality indices were also assessed according to European Brewing Convention (EBC) standards. Principal component analysis (PCA) was carried out on mean-centred, normalized and derivative spectra using 200/cm width spectral bands. The most informative spectral bands were observed in the 800-1,000/cm and 1,000-1,200/cm ranges. PCA revealed that barley harvested in 2010 and in 2011 had bands that were very close together, while 2009 harvest clearly displayed a difference in its quality. PCA made it possible to distinguish two species and confirmed that two-row winter barley quality was closer to two-row spring barley quality than to six-row winter barley. Results indicate that mid-infrared spectrometry (MIR) could be a very useful and rapid analytical tool to assess barley qualitative quality. 展开更多
关键词 Malting barley mean infrared spectroscopy principal components analysis.
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Utilization of Hydrocarbons Obtained by Waste Plastic Pyrolysis: Energetic Utilization (Part Ⅰ) 被引量:1
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作者 Norbert Miskolczi Laszlo Bartha 《Journal of Energy and Power Engineering》 2012年第8期1204-1210,共7页
The pyrolysis of different waste polymers (polyethylene, polypropylene and polystyrene) was investigated in a tube reactor at 550 ℃ in the absence of oxygen. Additionally the energetic utilization of products have ... The pyrolysis of different waste polymers (polyethylene, polypropylene and polystyrene) was investigated in a tube reactor at 550 ℃ in the absence of oxygen. Additionally the energetic utilization of products have also been followed both in refining and petrochemical industry. Pyrolysis products were separated into fractions of gases, naphtha, middle distillates and heavy oil. Raw materials have been collected both from industrial and household sources: polyethylene from agriculture, polyethylene from packaging and polystyrene from packaging and electronic equipments. Yields and properties of volatile products have changed by the raw materials. Products have been analyzed by gas chromatography. Fourier transformed infrared spectroscopy, size exclusion chromatography and other standardized methods. Naphtha had high octane numbers (80 〈 RON), while high cetane numbers (〉 75) in case of middle distillates. Moreover fractions contained approximately half of unsaturated hydrocarbons, mainly α-olefins, but the percentage was depending on the raw materials. These properties are advantageous for fuel-like applications. 展开更多
关键词 Plastic wastes PYROLYSIS energetic utilization refining.
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The Impact of Political Islam on Global IR & Prospects for Middle East Stability
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作者 Ahmed Y. Zohny 《Cultural and Religious Studies》 2016年第9期589-597,共9页
This work traces the historical development and impact of political Islam on international relations (IR) from the last century to date. In this article the author asserts that understanding the rise of political Is... This work traces the historical development and impact of political Islam on international relations (IR) from the last century to date. In this article the author asserts that understanding the rise of political Islam at the world's stage and IR generally can be genealogically traced to two interrelated developments: the rise of the Muslim Brotherhood (MB) in Egypt since 1928 as a social and political movement against the growing Western influence in the Islamic World after the collapse of the ottoman empire; and the development of the post-World War II IR theories, and practices which provided the basis of the political, military, and security doctrines of the United States and its allies which proved its lack of reliability and validity, particularly as related to the Muslim World, and the role of religion within the Muslim states and place of religion in global politics. 展开更多
关键词 political Islam Muslim brotherhood EGYPT IR theories Middle East role of religion in politics
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Study on Crystallization of Titanium Silicalite Zeolite (Ⅱ)
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作者 Lin Min Zhu Bin +1 位作者 Shu Xingtian Wang Xieqing (Research Institute of Petroleum Processing, Beijing 100083) 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2009年第1期31-38,共8页
In order to investigate the rules on formation of zeolite during crystallization of titanium silicalite zeolite (TS-1) the X-ray diffractometry and Foulier transform infra-red spectrometry were applied to track the pr... In order to investigate the rules on formation of zeolite during crystallization of titanium silicalite zeolite (TS-1) the X-ray diffractometry and Foulier transform infra-red spectrometry were applied to track the process of crystallization of titanium silicalite zeolite. The research results revealed that at the initial stage of crystallization the interactions between silica gel and titania gel in the polymer blend could gradually lead to the formation of tiny crystal nuclei with complicated structure that could slowly grow up to form molecular sieves. Quite different from the conventional zeolites that use the acid sites as the catalytically active centers, the oxidative reactivity of the titanium silicalite zeolite was not proportional to its crystallinity and is associated with the oxidative centers of titanium contained in the zeolite. 展开更多
关键词 titanium silicalite zeolite TS- 1 hollow titanium silicalite HTS CRYSTALLIZATION CHARACTERIZATION
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Determination of Soil Parameters in Apple-Growing Regions by Near-and Mid-Infrared Spectroscopy 被引量:8
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作者 DONG Yi-Wei YANG Shi-Qi +5 位作者 XU Chun-Ying LI Yu-Zhong BAI Wei FAN Zhong-Nan WANG Ya-Nan LI Qiao-Zhen 《Pedosphere》 SCIE CAS CSCD 2011年第5期591-602,共12页
Soil quality monitoring is important in precision agriculture.This study aimed to examine the possibility of assessing the soil parameters in apple-growing regions using spectroscopic methods.A total of 111 soil sampl... Soil quality monitoring is important in precision agriculture.This study aimed to examine the possibility of assessing the soil parameters in apple-growing regions using spectroscopic methods.A total of 111 soil samples were collected from 11 typical sites of apple orchards,and the croplands surrounding them.Near-infrared(NIR) and mid-infrared(MIR) spectra,combined with partial least square regression,were used to predict the soil parameters,including organic matter(OM) content,pH,and the contents of As,Cu,Zn,Pb,and Cr.Organic matter and pH were closely correlated with As and the heavy metals.The NIR model showed a high prediction accuracy for the determination of OM,pH,and As,with correlation coefficients(r) of 0.89,0.89,and 0.90,respectively.The predictions of these three parameters by MIR showed reduced accuracy,with r values of 0.77,0.84,and 0.92,respectively.The heavy metals could also be measured by spectroscopy due to their correlation with organic matter.Both NIR and MIR had high correlation coefficients for the determination of Cu,Zn,and Cr,with standard errors of prediction of 2.95,10.48,and 9.49 mg kg-1 for NIR and 3.69,5.84,and 6.94 mg kg-1 for MIR,respectively.Pb content behaved differently from the other parameters.Both NIR and MIR underestimated Pb content,with r values of 0.67 and 0.56 and standard errors of prediction of 3.46 and 2.99,respectively.Cu and Zn had a higher correlation with OM and pH and were better predicted than Pb and Cr.Thus,NIR spectra could accurately predict several soil parameters,metallic and nonmetallic,simultaneously,and were more feasible than MIR in analyzing soil parameters in the study area. 展开更多
关键词 heavy metals partial least square regression prediction accuracy soil quality spectroscopic method
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Determination of Spectrum Characteristic of Near Infrared Radiated by Indirect Moxibustion 被引量:5
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作者 杨华元 肖元春 +2 位作者 刘堂义 顾训杰 夏锦杉 《Journal of Acupuncture and Tuina Science》 2005年第6期55-57,共3页
MS96A type spectrum analyzer was applied to determine the spectral characteristic of near infrared radiated by moxa stick moxi-bustion, ginger-partitioned moxibustion, garlicpartitioned moxibustion and Aconium Carmich... MS96A type spectrum analyzer was applied to determine the spectral characteristic of near infrared radiated by moxa stick moxi-bustion, ginger-partitioned moxibustion, garlicpartitioned moxibustion and Aconium Carmichaeli-p ar titioned moxibustion. The spectrum of moxa stick moxibustion was relatively discrete and several wave crests are appeared. But in the spectrum of ginger-partitioned moxibustion, garlic-partitioned moxibustion or Aconium Carmichaeli partitioned moxibustion, a specific and relatively steady wave crest formed respectively. It was concluded different indirect moxibustion could bring respective spectrum of near infrared and have the relevant physiologic and biochemical effects. 展开更多
关键词 Indirect Moxibustion Near Infrared Spectrum ACUPUNCTURE-MOXIBUSTION
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