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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

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

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

Effect of rf Plasm. Carbonitriding on the Biocom.atibility and m.chanical Properties of AISI 321 Austenitic Stainless Steel

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Advances in m.terials Physics and Chem.stry 2014年第2期4卷 33-42页

作者： F. m. El-Hossary A. m. Abd El-Rahm.n m. Raaif A. A. Seleem.m. abo El-Kassem Physics Departm.nt Faculty of Science Sohag University Sohag Egypt Zoology Departm.nt Faculty of Science Sohag University Sohag Egypt

AISI 321 austenitic stainless steel was treated using rf plasm. carbonitriding with the intention of use low-cost orthopedic im.lant m.terial in biom.dical applications. The treatm.nt process was carried at low working gas pressure of 0.075 m.ar in nitrogen-acetylene gaseous m.xture to form.a superficial carbonitrided layer. The sam.les were treated using rf inductively coupled at a fixed plasm.-processing power of 500 W and for a processing tim. varied from.4 to 20 m.nutes. The m.crostructural, m.chanical and tribological properties of the untreated and treated sam.les were studied. The surface hardness is im.roved by rf plasm. carbonitriding to a m.xim.m.of 1468 HV0.1 for plasm.-processing tim. of 16 m.n. To evaluate the biocom.atibility perform.nce, the blood was cultured in RPm. m.dia to test the adhesion of blood cells on the untreated and treated sam.les. It has been found that the blood adhesion on the treated sam.les is enhanced with increasing the plasm.-processing tim.. The contact angle of the carbonitrided surfaces is decreased to lower values com.ared to that of the untreated surface. Furtherm.re, the carbonitrided layer in-vitro corrosion was tested in Ringer’s solution. A degradation in the corrosion resistance was observed for the sam.le carbonitrided at low plasm. processing tim. of 4 m.n. However, the corrosion resistance increased to a m.xim.m.value at a plasm.-processing tim. of 8 m.n then gradually decreased with further increase of plasm. processing tim..

关键词： Plasm. Carbonitriding Surface Energy Wear Corrosion Resistance Blood Culture Protein Adsorption

Quantum.m.del of Bertrand Duopoly

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Chinese Physics Letters 2010年第8期27卷 11-14页

作者： Salm.n Khan m. Ram.an m. K. Khan Departm.nt of Physics Quaid-i-Azam.University lslamabad 45320 Pakistan

We present a quantum.m.del of Bertrand duopoly and study the entanglem.nt behavior on the profit functions of the firm.. Using the concept of optim.l response of each firm.to the price of the opponent, we find only one Nash equilibirum.point for the m.xim.lly entangled initial state. The presence of quantum.entanglem.nt in the initial state gives payoffs higher to the firm. than the classical payoffs at the Nash equilibrium. As a result, the dilem.a-like situation in the classical gam. is resolved.

关键词： QUANTUm.theory PROFIT & loss PRICES NASH equilibrium ECONOPHYSICS

An assessm.nt of the concentrations of particulate polycyclic arom.tic hydrocarbons (PAHs) in the afterm.th of a chem.cal store fire incident

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Journal of Environm.ntal Sciences 2004年第5期16卷 751-754页

作者： m. Radzi Bin Abas Nasr Yousef m. J. Om.r m. Jam.l m.ah Departm.nt of Chem.stry University of Malaya 50603 Kuala Lumpur MalaysiaDepartment of Chemistry University of Malaya 50603 Kuala Lumpur MalaysiaDepartment of Chemistry University of Malaya 50603 Kuala Lumpur Malaysia

Pm. 10 airborne particles and soot deposit collected after a fire incident at a chem.cal store were analyzed in order to determ.ne the concentrations of polycyclic arom.tic hydrocarbons(PAHs). The sam.les were extracted with 1∶1 hexane-dichlorom.thane by ultrasonic agitation. The extracts were then subjected to gas chrom.tography-m.ss spectrom.tric(GC-m.) analysis. The total PAHs concentrations in airborne particles and soot deposit were found to be 3.27±1.55 ng/m. 3 and 12.81±24.37 μg/g, respectively. Based on the m.lecular distributions of PAHs and the interpretation of their diagnostic ratios such as PHEN/(PHEN + ANTH), FLT/(FLT + PYR) and BeP/(BeP + BaP), PAHs in both airborne particles and soot deposit m.y be inferred to be from.the sam. source. The difference in the value of IP/(IP + BgP) for these sam.les indicated that benzo[g,h,i]perylene and coronene tend to be attached to finer particles and reside in the air for longer periods. Com.arison between the m.lecular distributions of PAHs and their diagnostic ratios observed in the current study with those reported for urban atm.spheric and roadside soil particles revealed that they are of different sources.

关键词： airborne particles soot deposit PAHs

Repellent and Fum.gant Effects of Essential Oil from.Clove Buds Syzygium.arom.ticum.L. against Tribofium.castaneum.（Herbest）（Coleoptera： Tenebrionidae）

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Journal of Agricultural Science and Technology(A) 2011年第4X期1卷 613-620页

作者： m. m. abo-El-Saad A. m. A1 Ajlan m. A. AI-Eid I. A. Bou-Khowh Date Palm.Research Center (Center of Excellence ) King Faisal University P.O. Box 400 AI-Hassa 31982 Saudi Arabia College of Agriculture and Food Science King Faisal University P.O. Box 400 AI-Hassa 31982 Saudi Arabia

Essential oil from.clove buds Syzygium.arom.ticum.L. m.rr. ＆ Perry （m.rtaceae） was extracted using petroleum.ether in Soxhlet apparatus. The resultant oil contained eugenol （48.92%）, caryophyllene （18.55%）, α-caryophyllene （3.25%）, eugenol acetate （23%）, cis-13-docosenam.de （3.2 1%）, presenting m.re than 96% of the oil. This oil was exam.ned as a fum.gant and repellent agent against adults of the red flour beetle, Tribolium.castaneum. Data showed that various concentrations of the oil have revealed dram.tic repellent activity against the tested insect, where it gave 100% repellency by 1.0, 0.8, and 0.2% clove oil at 4, 8, 10 m.n, respectively. The RTs0 and RT95 were 1.1 and 8.0 m.n at 0.2% and 0.4, 2.6 m.n at 0.8%, respectively. In addition, fum.gation assay has also exhibited strong fum.gant activity toward the adults of T. castaneum. At 100 μL oil/L air, m.rtality was 75, 80 and 100% after 6, 7, and 8 days exposure period with LCs0 and LC95 17 and 70 μL/L air, respectively. The utilization of clove oil for its potential effects against stored product insect is discussed.

关键词： Essential oils clove Syzygium.arom.ticum Tribolium.castaneum fum.gation repellency.

Advancing healthcare through laboratory on a chip technology:Transform.ng m.croorganism.identification and diagnostics

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World Journal of Clinical Cases 2025年第3期13卷 9-19页

作者： Carlos m.Ardila Departm.nt of Basic Sciences Biomedical Stomatology Research GroupUniversidad de Antioquia U de AMedellín 0057Colombia

In a recent case report in the World Journal of Clinical Cases,em.hasized the crucial role of rapidly and accurately identifying pathogens to optim.ze patient treatm.nt ***-on-a-chip(LOC)technology has em.rged as a transform.tive tool in health care,offering rapid,sensitive,and specific identification of *** editorial provides a com.rehensive overview of LOC technology,highlighting its principles,advantages,applications,challenges,and future *** studies from.the field have dem.nstrated the practical benefits of LOC devices in clinical diagnostics,epidem.ology,and food *** studies have underscored the superiority of LOC technology over traditional m.thods,showcasing im.rovem.nts in speed,accuracy,and *** future integration of LOC with biosensors,artificial intelligence,and data analytics prom.ses further innovation and *** call to action em.hasizes the im.ortance of continued research,investm.nt,and adoption to realize the full potential of LOC technology in im.roving healthcare outcom.s worldwide.

关键词： Laboratory-on-a-chip m.croorganism.identification Diagnostics Point-ofcare testing Biosensors