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Petrological and mineralogical characteristics of younger granites and pegmatites in the Wadi Haleifiya area, southeastern Sinai, Egypt

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Chinese journal Of geochemistry 2011年第3期30卷 304-316页

作者： El gharbawy R.I. El Feky m.g. El galy m.m. El maadawy W.m. Faculty of Science Ain Shams Univeristy Cairo Egypt Nuclear materials Authority P.O. Box 030 Maadi Egypt

This study is concerned with the radioactivity and mineralogy of the younger granites and pegmatites in the Wadi Haleifiya area, southeastern Sinai Peninsula, Egypt. The area is occupied by metasediments, m.g.atites, older and younger granites. most of these rocks, especially granites, are dissected by mafic and felsic dykes as well as pegmatites. The younger granites are represented by three main varieties: monzogranites, syenogranites and alkali feldspar granites. The monzogranite consists essentially of quartz, plagioclase, potash feldspar and biotite with minor musco-vite. Iron oxide, titanite, zircon and allanite are the main accessory minerals. Syenogranite is massive, medium- to coarse-grained and commonly exhibits equigranular and hypidiomorphic textures. It is made up essentially of potash feldspar, quartz, plagioclase and biotite. Iron oxides, allanite, epidote, titanite, and zircon are accessory minerals. The alkali feldspar granite consists mainly of perthite, quartz, alkali amphibole (arfvedsonite and riebekite), biotite, sub-ordinate plagioclase and aegirine. Iron oxide, zircon and apatite are accessory minerals, whereas chlorite and sas-surite are secondary minerals. The altered monzogranite and pegmatite recorded high radioelement contents. The eU reaches up to 120 (av.=82×10-6) in the altered monzogranite and up to 55 (av.=27×10-6) in the pegmatites. The high radioactivity in the altered monzogranite is due to the presence of thorite, uranothorite and metamict zircon. In the pegmatites, it is re-lated to the presence of uranophane, uranothorite, thorite, zircon, samarskite, monazite, xenotime, m.g.etite, ilmen-ite, hematite and rutile.

关键词：二长花岗岩矿物学特征西奈半岛伟晶岩东南部岩石学埃及碱长花岗岩

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Dynamic properties of chasers in a moving queue based on a delayed chasing model

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Chinese Physics B 2016年第5期25卷 106-110页

作者：郭宁丁建勋凌翔石琴 Reinhart Kühne School of Engineering Science University of Science and Technology of China Hefei 230026 China School of Transportation Engineering Hefei University of Technology Hefei 230009 China Key Laboratory of Process Optimization and Intelligent Decision-making of ministry of Education Hefei 230009 China Department for Transportation University of Stuttgart Stuttgart 70174 Germany

A delayed chasing model is proposed to simulate the chase behavior in the queue, where each member regards the closest one ahead as the target, and the leader is attracted to a target point with slight fluctuation. When the initial distances between neighbors possess an identical low value, the fluctuating target of the leader can cause an amplified disturbance in the queue. After a long period of time, the queue recovers the stable state from the disturbance, forming a straightline-like pattern again, but distances between neighbors grow. Whether the queue can keep stable or not depends on initial distance, desired velocity, and relaxation time. Furthermore, we carry out convergence analysis to explain the divergence transformation behavior and confirm the convergence conditions, which is in approximate agreement with simulations.

关键词： chase queue disturbance convergence analysis

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Responses of Soil microbial Community Structure and Diversity to Agricultural Deintensification

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Pedosphere 2005年第4期15卷 440-447页

作者： ZHANg Wei- jian RUI Wen-Yi C. TU H. g. DIAB F. j. LOUWS j. P. mUELLER N. CREAmER m. BELL m.g. WAggER S. HU Department of Agronomy Nanjing Agricultural University Nanjing 210095 （China） Department of Plant Pathology North Carolina State University Raleigh NC 27695 （USA） Department of Crop Science North Carolina State University Raleigh NC 27695 （USA） Department of Horticultural Science North Carolina State University Raleigh NC 27695 （USA） Department of Soil Science North Carolina State University Raleigh NC 27695 （USA）

Using a scheme of agricultural fields with progressively less intensive management (deintensification), different manage- ment practices in six agroecosystems located near goldsboro, NC, USA were tested in a large-scale experiment, including two cash-grain cropping systems employing either tillage (CT) or no-tillage (NT), an organic farming system (OR), an integrated cropping system with animals (IN), a successional field (SU), and a plantation woodlot (WO). microbial phos- pholipid fatty acid (PLFA) profiles and substrate utilization patterns (BIOLOg ECO plates) were measured to examine the effects of deintensification on the structure and diversity of soil microbial communities. Principle component analyses of PLFA and BIOLOg data showed that the microbial community structure diverged among the soils of the six systems. Lower microbial diversity was found in lowly managed ecosystem than that in intensive and moderately managed agro- ecosystems, and both fungal contribution to the total identified PLFAs and the ratio of microbial biomass C/N increased along with agricultural deintensification. Significantly higher ratios of C/N (P ms, and for fungal/bacterial PLFAs in the WO system (P gnificant decreases (P g with agricultural deintensification for contributions of total bacterial and gram positive (g+) bacterial PLFAs. Agricultural deintensification could facilitate the development of microbial communities that favor soil fungi over bacteria.

关键词： agricultural deintensification agroecosystems carbon retention soil microbial community

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Nonlinear forced vibration in a subcritical regime of a porous functionally graded pipe conveying fluid with a retaining clip

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 101-122页

作者： m.g.OLAmI m.EFTEKHARI Department of mechanical Engineering Shahid Bahonar University of Kerman

This study examines the nonlinear behaviors of a clamped-clamped porous pipe made of a functionally graded material(Fgm) that conveys fluids and is equipped with a retaining clip, focusing on primary resonance and subcritical dynamics. The nonlinear governing equations for the Fgm pipe are derived by the extended Hamilton's principle, and subsequently discretized through the application of the galerkin *** direct method of multi-scales is then used to solve the derived equations. A thorough analysis of various parameters, including the clip stiffness, the power-law index, the porosity, and the clip location, is conducted to gain a comprehensive understanding of the system's nonlinear dynamics. Through the analysis of the first natural frequency, the study highlights the influence of the flow velocity and the clip stiffness, while the comparisons with metallic pipes emphasize the role of Fgm composition. The examination of the forced response curves reveals saddle-node bifurcations and their dependence on parameters such as the detuning parameter and the power-law index, offering valuable insights into the system's nonlinear resonant behavior. Furthermore, the frequency-response curves illustrate the hardening nonlinearities influenced by factors such as the porosity and the clip stiffness, revealing nuanced effects on the system response and resonance characteristics. This comprehensive analysis enhances the understanding of nonlinear behaviors in Fgm porous pipes with a retaining clip, providing key insights for practical engineering applications in system design and optimization.

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Development and characterization of a microfluidic glucose sensing system based on an enzymatic microreactor and chemiluminescence detection

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Science China Chemistry 2012年第4期55卷 515-523页

作者： mOON B.-U. de VRIES m.g. WESTERINK B.H.C. VERPOORTE E. Biomonitoring and Sensoring Department of Pharmacy University of Groningen Antonius Deusinglaan 1 9713AV Groningen The Netherlands Pharmaceutical Analysis Department of Pharmacy University of Groningen Antonius Deusinglaan 1 9713AV Groningen The Netherlands Brains-on-Line PO Box 4030 9713AV Groningen The Netherlands

Chemiluminescence detection was developed as an alternative to amperometric detection for glucose analysis in a portable, microfluidicsbased continuous glucose monitoring system. Amperometric detection allows easy determination of hydrogen peroxide, a product of the glucose oxidasecatalyzed reaction of glucose with oxygen, by oxidation at a microelectrode. However, （micro）electrodes in direct contact with physiological sample are subject to electrode fouling, which leads to signal drift, decreased reproducibility and shortened detector lifetimes. moreover, there are a few species present in the body （e.g. ascorbic acid, uric acid） which can undergo oxidation at the same applied potential as hydrogen peroxide. These species can thus inter- fere with the glucose measurement, reducing detection specificity. The rationale for exploring chemiluminescence as opposed to amperometric detection is thus to attempt to improve the lifetime and reproducibility of glucose analysis for monitoring purposes, while reducing interference caused by other chemicals in the body. The study reported here represents a first step in this direction, namely the realization of a microfluidic device with integrated silicon photodiode for chemiluminescence detection of glucose. This microflow device uses a chaotic mixing approach to perform enzymatic conversion of glucose, followed by reaction of the hydrogen peroxide produced with luminol to produce light at 425 nm. The chemil reaction is catalyzed by horseradish peroxidase in the presence of iodophenol. The performance of the fabricated chip was characterized to establish optimal reaction conditions with respect to sample and reagent flow rates, pH, and concentrations. A linear calibra- tion curve was obtained for current response as a function of glucose concentration in the clinically relevant range between 2 and 10 mm, with a sensitivity of 39 pA/mm （R = 0.9963, one device, n = 3） and a limit of detection of 230 ktm （S/N - 3）.

关键词： microfluidic chip – glucose sensing system – enzymatic microreactor – chemiluminescence – chaotic mixing

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Evaluation of genetic diversity in short duration cotton(gossypium hirsutum L.)

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journal of Cotton Research 2018年第4期1卷 12-17页

作者： AKTER T. ISLAm A.K.m.A. RASUL m.g. KUNDU S. KHALEQUZZAmAN AHmED j.U. Department of genetics and Plant Breeding Bangabandhu Sheikh Mujibur Rahman Agricultural University Cotton Development Board (CBD) Department of Crop Botany Bangabandhu Sheikh Mujibur Rahman Agricultural University

Background: Cotton(gossypium hirsutum L.) is an important fiber crop in Bangladesh. genetic diversity among the genotypes of a germplasm has a great importance for cotton breeding. An experiment was carried out at the experimental field of Cotton Research, Training and Seed multiplication Farm, Sreepur, gazipur during the cropping season of 2015-2016 with 100 genotypes to evaluate genetic diversity of cotton genotypes for short duration using field ***: The genotypes under study were grouped into ten clusters through multivariate analysis using *** III contained maximum number of genotypes(16) while cluster X contained the least number of genotypes(7).The inter cluster distances were larger than intra cluster distances in all cases suggesting wider genetic diversity among the genotypes of different clusters. The maximum and minimum inter cluster distances were observed between clusters II and V(10.78) and clusters VIII and IX(3.30), respectively. The results indicated diverse and close relationship among the genotypes of those clusters. Earliness index, single boll weight and days to boll opening showed the higher contribution to the genetic divergence among 19 ***: Based on the results of genetic diversity and earliness index, the genotypes from cluster Ⅱ could be used as parent in hybridization program for the development of short duration cotton variety.

关键词： Cotton(gossypium hirsutum L.) genetic diverity Earliness index gOT Yield

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glia-to-neuron reprogramming to the rescue?

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Neural Regeneration Research 2025年第5期20卷 1395-1396页

作者： jack W.Hickmott Cindi m.morshead Department of Surgery University of TorontoTorontoONCanada Donnelly Centre for Cellular and Biomolecular Research TorontoONCanada Institute of Biomedical Engineering University of TorontoTorontoONCanada The KITE Research Institute Toronto Rehabilitation InstituteUniversity Health NetworkTorontoONCanada

Over the last two decades,the dogma that cell fate is immutable has been increasingly challenged,with important implications for regenerative *** brea kth rough discovery that induced pluripotent stem cells could be generated from adult mouse fibroblasts is powerful proof that cell fate can be *** exciting extension of the discovery of cell fate impermanence is the direct cellular reprogram ming hypothesis-that terminally differentiated cells can be reprogrammed into other adult cell fates without first passing through a stem cell state.

关键词： programming passing proof

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DISSOLUTION KINETICS OF PHOSPHATE ORE IN ACIDIC SOLUTIONS

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Chinese journal of Chemical Engineering 1994年第2期2卷 13-22页

作者：马三剑 E.T.m.j.martynowicz g.j.Witkamp g.m.vanRosmalen Faculty of Chemical Technology and material Science Delft University of TechnologyLeeghwaterstraat 442628RZ DelftThe Netherlands

The dissolution kinetics of Florida and jordan phosphate ore was studied in diluted nitric acid (0.2, 0.5, 1.0 mol ·L-1), and in phosphoric acid (55 wt% H3PO4) aqueous solutions. It was found that the hydrogen ions concentration is a controlling factor, but the calcium ions concentration can not affect the dissolution rate in the range of 0.0 and 2.0 wt% Ca2+. The effects of temperature, stirring intensity and the size of ore particles were also investigated. The transfer of hydrogen ion depends on the diffusion, while the calcium ions transfer is assumed to be depended on mechanically stripping. The shrinking core model with hydrogen ions diffusion control match the experimental results.

关键词： dissolution kinetics phosphate ore diffusion mechanically stripping hydrogen calcium ions concentration shrinking core model

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Influence of cerium content on the corrosion behavior of Al-Co-Ce amorphous alloys in 0.6 m NaCl solution

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journal of materials Science & Technology 2019年第7期35卷 1378-1387页

作者： L.m.Zhang S.D.Zhang A.L.ma A.j.Umoh H.X.Hu Y.g.Zheng B.j.Yang j.Q.Wang CAS Key Laboratory of Nuclear materials and Safety Assessment Institute of Metal ResearchChinese Academy of Sciences62 Wencui RoadShenyang 110016PR China School of materials Science and Engineering University of Science and Technology of China72 Wenhua RoadShenyang 110016PR China Shenyang National Laboratory for materials Science Institute of Metal ResearchChinese Academy of Sciences72 Wenhua RoadShenyang 110016PR China

The effect of cerium content on the corrosion behavior of Al-Co-Ce amorphous alloys in 0.6 m NaCl solution was investigated by cyclic polarization, mott-Schottky and X-ray photoelectron spectroscopy techniques. Results indicated that the open circuit potential of Al-Co-Ce amorphous alloys displayed a decreased tendency with the increase in Ce content, and the amorphous alloy with 4 at.% Ce presented both the lowest passive current density and donor density indicating the best corrosion resistance, while adding excess Ce led to the reduced corrosion resistance of Al-Co-Ce alloys, Furthermore, it was found that a low Ce content is beneficial to the formation of a more protective passive film on Al-Co-Ce amorphous alloys, and the corrosion inhibition reactions of Al-Co-Ce alloys in 0.6 m NaCl solution were changed with the increase in Ce content and the detailed reasons were discussed.

关键词： Amorphous materials Polarization Corrosion Photoelectron spectroscopies

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ON THE IDENTIFICATION OF RESIDUAL ImPACT PROPERTIES OF mATERIALS BY ACOUSTO-ULTRASONICS——A PATTERN RECOgNITION APPROACH

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Acta mechanica Sinica 1995年第1期11卷 34-43页

作者： g.j.molina Y.m.Haddad Dept.of mechanical Engineering University of OttawaOttawaCanada K1N 6N5

This paper deals with the application of Acousto-ultrasonics,in con- junction with Pattern Recognition and Classification techniques,to the identification of residual impact properties of a class of polymeric material,namely,Polyvinylchlo- ride(PVC).PVC specimens of different low-energy repeated impact dam.g. states are processed by Acousto-ultrasonics(AU)to retrieve AU signals in the form of dig- italized *** AU signals are grouped as distinct classes,each pertaining to a known level of repeated impact *** features of these AU signals are used to build Pattern Recognition(PR)*** classifiers are used to identify unknown dam.g. states in other PVC specimens by classifying the re- trieved AU signals as belonging to one of the *** obtained results indicate that Acousto-ultrasonics in combination with Pattern Recognition and Classification techniques can be used for the quantitative non-destructive identification of dam.g. states in PVC specimens of unknown low-energy repeated impact conditions.

关键词： pattern recognition acousto-ultrasonics impact dam.g. quantitative non-destructive examination

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