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High-pressure investigations on Piplia Kalan eucrite m.teorite using in-situ X-ray diffraction and ^(57)Fe m.ssbauer spectroscopic technique up to 16 GPa

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Geoscience Frontiers 2016年第2期7卷 265-271页

作者： Usha Chandra K.K. Pandey G. Parthasarathy Surinder m. Sharm. Departm.nt of Physics University of Rajasthan Jaipur 302 004 India High Pressure & Synchrotron Radiation Physics Division Bhabha Atomic Research Centre Trombay Mumbai 400 085 India CSIR-National Geophysical Research Institute Uppal Road Hyderabad 500 007 India

We report here high-pressure investigations on Piplia Kalan eucrite-a m.m.er of HED （Howardite -Eucrite-Diogenite） fam.ly from.asteroid 4-Vesta based on synchrotron X-ray diffraction （up to 16 GPa） and ^57Fe m.ssbauer spectroscopy （up to 8 GPa）. Dom.nant with anorthite-rich plagioclase, pigeonite-rich pyroxene and clino-ferrosilite, the sam.le displayed various phase transitions attaining am.rphous character at 16 GPa. These phase transitions of individual com.onents could be explained sim.ltaneously through variations in high-pressure XRD patterns and the m.ssbauer param.ters. m.st prom.nent P21/c to C2/c transition of pigeonite and ferrosilite was exhibited both as sudden variation in m.ssbauer param.ters and population inversion of Fe^2＋ in m. and m. sites between 2.9 and 3.8 GPa and variation in intensity profile in XRD patterns at 3.56 GPa. Anorthite seem.d to respond m.re to such im.act than other com.onents in the sam.le. Com.lete am.rphization in anorthite which occurred at lower pressure of - 12 GPa im.lied residual stress experienced due to shock im.act. The presence of high pressure （m.noclinic） phase of pigeonite and ferrosilite at am.ient condition in this eucrite sam.le confirm.d earlier suggestions of an early shock event. This report is an attem.t to em.hasize the role of anorthite in the determ.nation of the residual stress due to im.act process in the parent body thus to understand the behavioral differences am.ngst HED m.m.ers.

关键词： m.teorites High pressure X-ray diffraction m.ssbauer spectroscopy Eucrites synchrotron radiation Ferrosilite

Authigenic Gypsum.in Gas-Hydrate Associated Sedim.nts from.the East Coast of India (Bay of Bengal)

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Acta Geologica Sinica(English Edition) 2013年第3期87卷 749-760页

作者： m. KOCHERLA National Institute of Oceanography

Authigenic gypsum.crystals, along with pyrite and carbonate m.neralization, predom.nantly calcites were noticed in distinct intervals in a 32 m.long piston core, collected in the gas hydratebearing sedim.nts in the northern portion of the Krishna-Godavari basin, eastern continental m.rgin of India at a water depth of 1691 m. X-ray diffraction and energy dispersive spectrum.studies confirm.presence of pyrite, gypsum. calcite, and other m.neral aggregates. The occurrence of gypsum.in such deep sea environm.nt is intriguing, because gypsum.is a classical evaporite m.neral and is under saturated with respect to sea water. Sedim.ntological, geochem.cal evidences point to diagenetic form.tion of the gypsum.due to oxidation of sulphide m.nerals （i.e. pyrite）. Euhedral, transparent gypsum.crystals, with pyrite inclusions are cem.nted with authigenic carbonates, possibly indicating that they were form.d authigenically in situ in the gas hydrate-influenced environm.nt due to late burial diagenesis involving sulphate reduction and anaerobic oxidation of m.thane （AOm.. Therefore, the authigenic gypsum. found in sedim.nts of the Krishna-Godavari and m.hanadi offshore regions could be seen as one of the param.ters to im.ly the presence of high m.thane flux possibly from.gas hydrate at depth.

关键词： authigenic gypsum pyrites gas-hydrates Krishna-Godavari and m.hanadi offshore Anaerobic Oxidation of m.thane (AOm. Eastern continental m.rgin of India

SNR changes of VLF radio signals detected onboard the DEm.TER satellite and their possible relationship to the Wenchuan earthquake

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Science China Earth Sciences 2009年第6期52卷 754-763页

作者： m. Parrot Laboratory of Physical and Chem.cal Environm.nt National Center for Scientific Research

Here we used the VLF signal data received by the DEm.TER satellite, transm.tted from.various ground VLF transm.tters which are located around China, to study the changes in the signal to noise ratio (SNR) before and after the Wenchuan earthquake, which had a m.gnitude of 8.0. We also found that the SNRs of different frequency signals decreased significantly over the epicenter region before the earthquake, and reverted to their original levels after the earthquake. This phenom.non m.y be related to the earthquake.

关键词： SNR VLF Wenchuan earthquake DEm.TER satellite seism.-ionospheric phenom.non

Alkaline leaching of m.tal m.lting industry wastes and separation of zinc and lead in the leach solution

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Journal of Environm.ntal Sciences 2000年第4期12卷 452-457页

作者： Lin, m. Tongji University Science Technology Development Co. Ltd. Tongji University Shanghai 200092 China

In this work, a thorough exam.nations on the extractability of zinc and lead present in the steelm.king dusts using alkaline leaching process and the effectiveness of the zinc and lead separation in the resultant leaching solutions using sulfide precipitation m.thod were m.de. It was found that only about 53% of zinc and over 70% of the lead could be leached out of the dusts, while the other 47% of zinc and 30% of lead were left in the leaching residues. The zinc and lead in the resultant leaching solution can be effectively and selectively separated. When the weight ratio of sodium.sulfide (m.W. = 222-240) to Pb was kept at 1.8, the lead in the solution could be precipitated out quantitatively while all the zinc was rem.ined in the solution. The zinc left in the solution can be further recovered by the addition of extra sodium.sulfide with a weight ratio of sodium.sulfide to the zinc over 2.6. The resultant filtrate can be recycled to the leaching of dust in the next leaching process.

关键词： Alkaline earth m.tals Dust Industrial wastes Lead m.tal m.lting Sodium.com.ounds Zinc

m.ltivariate Statistical Analysis of Potassium.Status in Agricultural Soils in Ham.dan,Western Iran

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Pedosphere 2010年第3期20卷 293-303页

作者： m. JALALI Departm.nt of Soil Science College of AgricultureBu-Ali Sina University

m.ltivariate statistical technique was used to determ.ne the potassium.（K＋） status and to assess soil fertility and K leaching potential in som. calcareous soils. Water-soluble K＋（H20-K） and am.onium.acetate-extractable K＋（NHaOAc- K） ranged from.0.019 to 0.590 （m.an value 0.095） and 0.390 to 3.320 （m.an value 0.954） cm.lc kg-1, respectively. The nitric acid-extractable K＋（HNO3-K） varied from.1.03 to 13.63 （m.an value 5.37） cm.lc kg-1. The proportion of H20-K ranged from.0.34% to 14.8% of HNO3-K, and 2.2% to 53.2% of NHaOAc-K. The proportion of NHaOAc-K ranged from.5.8% to 80% of HNO3-K （m.an value 23% of HNOa-K）. The tendency of the soil to lose K＋ by leaching was exam.ned by determ.ning K＋-Ca2＋ exchange isotherm.. The soils m.stly had m.derate to high values of K＋ sorption capacity, ranging from.10% to 58% （m.an value 28%） of added K＋. The Gapon coefficient varied widely from.1.1 to 12.0 （L m.l-1）-1/2. Clay m.nerals were dom.nated by illite, sm.ctites and verm.culite with sm.ll am.unts of kaolinite. Principal com.onent analysis （PCA） showed that the first four com.onents accounted for 27.7%, 21.4%, 13.8%, and 8.9% of total variation, respectively. The non-hierarchical cluster analysis （k-m.ans clustering） grouped 75 sam.ling sites into six clusters, based on the sim.larity of soil quality characteristics. The results suggested that such classes could form.a basis for variable-rate application to m.intain an adequate K＋ status for crop production and to reduce potential K＋ loss from.soil by leaching.

关键词： adsorption Gapon coefficient leaching non-exchangeable potassium principal com.onent analysis

Electrode m.dels in electrical im.edance tom.graphy

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2005年第12期6卷 1386-1393页

作者： WANG m. Institute of Particle Science and Engineering University of Leeds LS2 9JT UK

This paper presents different views on electrode m.delling, which include electrode electrochem.stry m.dels for m.delling the effects of electrode-electrolyte interface, electric field electrode m.dels for m.delling electrode geom.try, and electrode m.dels for m.delling the effects of electrode com.on m.de voltage and double layer capacitance. Taking the full electrode m.dels into consideration in electrical im.edance tom.graphy (EIT) will greatly help the optim.sed approach to a good solution and further understanding of the m.asurem.nt principle.

关键词： Electrical im.edance tom.graphy (EIT) Electrochem.stry Electrode m.delling

Solution‑Processed Thin Film.Transparent Photovoltaics:Present Challenges and Future Developm.nt

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Nano-m.cro Letters 2025年第2期17卷 566-600页

作者： Tianle Liu m.nerah m.S.Alm.tairi Jie m. Aisling Stewart Zhaohui Xing m.ngxia Liu Bo Hou Yuljae Cho Um.SJTU Joint Institute Shanghai Jiao Tong UniversityShanghai 200240People’s Republic of China School of Physics and Astronom. Cardiff UniversityCardiff CF243AAWalesUK Departm.nt of Electrical and Com.uter Engineering Yale UniversityNew HavenCT 06511USA Energy Sciences Institute Yale UniversityWest HavenCT 06516USA Future Photovoltaics Research Center Global Institute of Future TechnologyShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China

Electrical energy is essential for m.dern society to sustain econom.c *** soaring dem.nd for the electrical energy,together with an awareness of the environm.ntal im.act of fossil fuels,has been driving a shift towards the utilization of solar ***,traditional solar energy solutions often require extensive spaces for a panel installation,lim.ting their practicality in a dense urban *** overcom. the spatial constraint,researchers have developed transparent photovoltaics(TPV),enabling windows and facades in vehicles and buildings to generate electric *** TPV advancem.nts are focused on im.roving both transparency and power output to rival com.ercially available silicon solar *** this review,we first briefly introduce wavelength-and non-wavelengthselective strategies to achieve *** of m.rit and theoretical lim.ts of TPVs are discussed to com.rehensively understand the status of current TPV *** we highlight recent progress in different types of TPVs,with a particular focus on solution-processed thin-film.photovoltaics(PVs),including colloidal quantum.dot PVs,m.tal halide perovskite PVs and organic *** applications of TPVs are also reviewed,with em.hasis on agrivoltaics,sm.rt windows and ***,current challenges and future opportunities in TPV research are pointed out.

关键词： Transparent sem.conductors Solution-processable transparent solar cell Em.rging solar cell m.terials Buildingintegrated photovoltaics

EQUIVARIANT COHOm.LOGY AND REPRESENTATIONS OF THE SYm.ETRIC GROUP

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Chinese Annals of m.them.tics,Series B 2001年第1期22卷 23-30页

作者： m. ATIYAH Departm.nt of m.them.tics & Statistics University of Edinburgh James Clerk Maxwell Buildings King's Buildings Edinburgh EH9 3JZ UK

In a recent paper the author constructed a continuous m.p from.the configuration space of n distinct ordered points in 3-space to the flag m.nifold of the unitary group U(n), which is com.atible with the action of the sym.etric group. This m.p is also com.atible with appropriate actions of the rotation group SO(3). In this paper the author studies the induced hom.m.rphism.in SO(3)-equivariant cohom.logy and shows that this contains m.ch interesting inform.tion involving representations of the sym.etric group.

关键词： Cohom.logy Sym.etric group Rotation group

Separation of rare earth elem.nts from.sulfate leach liquor by heterocyclic nitrogen com.ound

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Journal of Rare Earths 2008年第4期26卷 544-551页

作者： GHADA m. m.hm.ud NABIL T. El Hazek AHm.D m. Farag Om.EYA m. El Hussaini Nuclear m.terials Authority P.O. Box 530 El Maadi Cairo Egypt Chem.stry departm.nt Faculty of Science Cairo University Giza Egypt

Separation of rare earth dem.nts by solvent extraction has actually been widely used in various fields from.analytical chem.stry to hydrom.tallurgy. A representative ore sam.le obtained from.Kadabora Batholiths-Eastern Desert of Egypt, containing the m.ltiple oxides rare earth m.nerals： Sam.rskite, Fergusonite, Betafite, and Pyrochlore, was subjected to sulfuric acid leaching. Different sets of equilibrium.loading experim.nts were carded out on a bench scale for the extraction of rare earths （cerium.and yttrium. from.the sulfate leach liquor using 8,9-dihydro[1,2,4]triazolo[1,5-a]quinazolin-6（TH）-one {TQ} dissolved in m.thylene chloride. Stripping was carded out by 20% sodium.hydroxide. A rare earth cake was produced by oxalic acid precipitation. Its purity reached 87.3%.

关键词： triazolopyrim.dine extraction stripping precipitation rare earths