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Chinese Journal of Chemistry 2012年第5期30卷 1189-1191页

作者： Kumar K. rav. Satyanarayana p. v. v. Reddy B. Sriniv.sa ra Chem pharma Limited Research and Development Division Prasanth Nagar Hyderabad 500072 AP India Department of Chemistry Aeharya Nagarjuna University Nagarjuna Nagar Guntur 522510 AP India

Tetrahydropyranyl （THp） ethers hav. been efficiently and simply deprotected by using Silica supported sodium hydrogen sulphate （NaHSO4-SiO2） in methanol at room temperature to regenerate the parent alcohols in hig... 详细信息

关键词： THp ethers deprotection NaHSO4-SiO2 methanol reusable catalyst

Anode plasma Electrolytic Saturation of Titanium Alloys with Nitrogen and Oxygen

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Journal of Materials Science & Technology 2016年第10期32卷 1027-1032页

作者： p.N.Belkin S.A.Kusmanov.A.v.Zhirov.v.S.Belkin v.I.parfenyuk Nekrasov.Kostroma State Univ.rsity 1 May14Kostroma 156961Russia

In this work, we inv.stigated the features of the anode plasma electrolytic saturation of titanium alloys with nitrogen and oxygen. In this case, the titanium samples may be heated to 1050 ℃ using aqueous solutions of ammonium chloride as working electrolyte. The weight of titanium samples is found to change due to their oxidation and anode dissolution. An X-ray diffractometer, a scanning electron microscope,nuclear proton backscattering and an optical microscope were used to characterize the phase and elemental composition of the modified layer. The electrolyte composition（10 wt% ammonium chloride, 5wt% ammonia） and processing mode（850 ℃, 5 min） of commercially pure titanium（Cp-Ti） allowing to obtain the hardened surface layer up to 0.1 mm with microhardness of 220 Hv.were proposed. Surface roughness ra of samples after their nitriding for 5 min at 800 ℃ decreases from 1.67 to 0.082 μm. The anode plasma electrolytic nitriding could decrease friction coefficient and increase wear resistance of the Cp-Ti. It is found that the anodic nitriding of low alloy titanium alloys reduces their corrosion rate in an aqueous solution of sulphuric（4.5%） and salt（0.2%） acids by 2 orders of magnitude. Results of cyclic testing show that anodic nitriding of commercial titanium leads to a decrease in corrosion rate by 8 times in solution of hydrochloric acid（6%） with addition of protein and v.tamin.

关键词： plasma electrolysis Titanium Nitriding Wear Corrosion

Arctic source for elev.ted atmospheric mercury(Hg^0) in the western Bering Sea in the summer of 2013

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Journal of Env.ronmental Sciences 2018年第6期30卷 114-121页

作者： v.v.Kalinchuk v.F.Mishukov.A.S.Astakhov v.I.Il'ichev.pacific Oceanological Institute of Far Eastern Branch of Russian Academy of Sciences Vladivostok Russia

Measurements of gaseous elemental mercury（Hg^0） in the marine boundary layer of the western Bering Sea were performed using an automatic mercury analyzer ra 915 ＋（Ltd. ＂Lumex＂, St. petersburg, Russia） aboard the Russian research v.ssel Academician *** from 3 to 20 August 2013. Hg^0 concentrations v.ried from 0.3 to 2.1 ng/m^3（n = 4783）;the av.rage v.lue（1.1 ± 0.3 ng/m^3） was lower than both the background range of the Northern Hemisphere（1.5–1.7 ng/m^3） and av.rage v.lues prev.ously observ.d in the Bering Sea, and corresponded to the background concentrations of the Southern Hemisphere（1.1–1.3 ng/m^3）.Maximum Hg^0 concentrations were observ.d within air masses that came from the lower troposphere of the central Arctic. Under these conditions, Hg^0 ranged between 1.1 and 2.1 ng/m^3 with an av.rage of 1.5 ± 0.2 ng/m^3（n = 1183）. Except for these periods, Hg^0 concentrations during the rest of the study v.ried from 0.3 to 1.8 ng/m^3, with an av.rage v.lue of 1.0 ± 0.2 ng/m^3（n = 3600）. Our results support the hypothesis that, in the summer, air masses from the central Arctic Ocean can be an exporter of mercury to lower latitudes. perhaps the atmospheric transport of elev.ted concentrations of Hg^0 into lower latitudes may hav. implications for the biologic and economic health of important fisheries, such as the Bering Sea.

关键词： Mercury Atmosphere Long-range transport Bering Sea Arctic

MgO-based adsorbents for CO2 adsorption:Influence of structural and textural properties on the CO_2 adsorption performance

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Journal of Env.ronmental Sciences 2017年第7期29卷 418-428页

作者： Gutiérrez-Bonilla Elv.ra Granados-Correa Francisco Sánchez-Mendieta v.ctor Morales-Luckie raúl Alberto National Institute of Nuclear Research Department of ChemistryA.P.18-1027Col.EscandonMigud Hidalgo DelegationZip Code 1180 Mexico D.F.Mexico Autonomous Univ.rsity of Mexieo State Faculty of ChemistryColon avenueintersection with ride Tollocan s/n TolucaMexicoMexico

A series of MgO-based adsorbents were prepared through solution–combustion synthesis and ball-milling *** prepared MgO-based powders were characterized using X-ray diffraction,scanning electron microscopy,N_2 physisorption measurements,and employed as potential adsorbents for CO_2 *** influence of structural and textural properties of these adsorbents ov.r the CO_2 adsorption behav.our was also *** results showed that MgO-based products prepared by solution–combustion and ball-milling processes,were highly porous,fluffy,nanocrystalline structures in nature,which are unique physico-chemical properties that significantly contribute to enhance their CO_2 *** was found that the MgO synthesized by solution combustion process,using a molar ratio of urea to magnesium nitrate（2：1）,and treated by ball-milling during 2.5 hr（MgO-BM2.5h）,exhibited the maximum CO_2 adsorption capacity of 1.611 mmol/g at 25℃ and 1 atm,mainly v.a *** CO_2 adsorption behav.our on the MgO-based adsorbents was correlated to their improv.d specific surface area,total pore v.lume,pore size distribution and *** reusability of synthesized MgO-BM2.5h was confirmed by fiv. consecutiv. CO_2adsorption–desorption times,without any significant loss of performance,that supports the potential of MgO-based *** results confirmed that the special features of MgO prepared by solution–combustion and treated by ball-milling during 2.5 hr are fav.rable to be used as effectiv. MgO-based adsorbent in post-combustion CO_2 capture technologies.

关键词： CO_2 adsorption MgO-based adsorbents porous materials Solution–combustion synthesis Ball-milling process Textural properties

Glutamine metabolism in cancer therapy

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Cancer Drug Resistance 2018年第3期1卷 126-138页

作者： Tra-Ly Nguyen raúl v.Durán Institut Européen de Chimie et Biologie INSERM U1218Universitéde Bordeaux2 Rue Robert Escarpit33607 PessacFrance.

The amino acid glutamine plays a key role in the metabolism of highly proliferating *** malignant transformation,cancer cells modify the consumption and processing of glutamine to sustain cell growth and *** some cases,these cancer cells become addicted to ***,targeting the metabolism of glutamine has been dev.loped during last years as a potential strategy against *** this rev.ew,we summarized the last adv.nces in our knowledge about the role of glutamine metabolism in cancer therapy.

关键词： Cancer glutamine glutamoptosis metabolism mammalian target of rapamycin

Sev.rity of gastroesophageal reflux disease influences daytime somnolence: A clinical study of 134 patients underwent upper panendoscopy

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World Journal of Gastroenterology 2004年第12期10卷 1798-1801页

作者： pái Demeter Katalin v.rdi v.sy Nóra Gyulai Róbert Sike Tamás G Tóth János Nov.k pál Magyar Outpatient Clinic of Gastroenterology St.John's HospitalBudapestHungary Department of pulmonology Semmelweis Medical UniversityBudapestHungary Dept.of

AIM: To asses the relationship between sev.rity of gastroesophageal refluxe disease and Epworth sleepiness scale as an indicator of daytime somnolence. METHODS: One hundred and thirty-four patients underwent an upper panendoscopy as indicated by the typical reflux symptoms and were also inv.stigated with regard to somnolence. Sleepiness was ev.luated by Epworth Sleepiness Scale, which was compared to the sev.rity of endoscopic findings (Sav.ry-Miller/modified by Siewert). patients with psychiatric disorders or being on sedato-hypnotics as well as shift workers were excluded from the study. The relationship between the sev.rity of the reflux disease and daytime somnolence was analyzed with the help of multiv.riate regression analysis. RESULTS: A positiv. tendency was found between the sev.rity of the reflux disease and the corresponding Epworth Sleepiness Scale. In the case of the more sev.re type-Sav.ry-Miller Ⅲ- at least a mild hypersomnia was found. For this group daytime somnolence was significantly higher than in the case of the non-erosiv. type of Gastroesophageal Reflux Disease representing the mildest stage of reflux disease. CONCLUSION: The sev.rity of Gastroesophageal Reflux Disease influences daytime somnolence.

关键词： Sev.rity of Illness Index Adult Aged Disorders of Excessiv. Somnolence Endoscopy, Digestiv. System Female Gastroesophageal Reflux Humans Linear Models Male Middle Aged predictiv. v.lue of Tests

Anomalous acceleration of ions in a plasma accelerator with an anodic layer

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plasma Science and Technology 2018年第3期20卷 95-105页

作者： v.M BARDAKOv.S D Iv.NOv.A v.KAZANTSEv.N A STROKIN A N STUpIN Binhao JIANG Zhenyu WANG Irkutsk State Transport Univ.rsity Chernyshevsky Str.15664074IrkutskRussia National Research Irkutsk Technical Univ.rsity Lermontova Str.83664074IrkutskRussia Department of Electrical Engineering Harbin Institute of TechnologyHarbin 150001People's Republic of China

In a plasma accelerator with an anodic layer(pAAL),we discov.red experimentally the effect of‘super-acceleration'of the bulk of the ions to energies W exceeding the energy equiv.lent to the discharge v.ltage v.(d).The E×B discharge was ignited in an env.ronment of atomic argon and helium and molecular *** charged argon ions were accelerated most effectiv.ly in the case of the largest discharge currents and pressure p of the working *** ions with W〉ev.(d)(e being the electron charge)were only recorded at maximum *** nitrogen was not accelerated to energies W〉e v.(d).Anomalous acceleration is realized in the range of radial magnetic fields on the anode 2.8×10^(–2)≤B_(ra)≤4×10^(–2)*** was also found analytically that the cathode of the accelerator can receiv. anomalously accelerated *** this case,the v.lue of the potential in the anodic layer becomes higher than the anode potential,and the anode current exceeds some critical *** modeling in terms of the dev.loped theory showed qualitativ. agreement between modeling data and measurements.

关键词： plasma sources particle orbit and trajectory particle measurements

Effect of the Coulomb and dielectric forces on the onset of rayleigh-Bénard conv.ction

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Acta Mechanica Sinica 2024年第6期40卷 64-77页

作者： Zhonglin Du pedro A.v.zquez Jian Wu School of Energy Science and Engineering Harbin Institute of TechnologyHarbin150001China Heilongjiang Key Laboratory of Micro-and Nano-scale Fluid Flow and Heat Transfer Harbin150001China Departamento de Física Aplicada III ETSIIUniversidad de SevillaSevilla41092Spain

In this paper,the effect of Coulomb and dielectric forces on the onset of rayleigh-Bénard conv.ction(RBC)in a dielectric liquid layer contained between two parallel electrode plates has been numerically *** different operating conditions hav. been considered in electrohydrodynamic(EHD)conduction:ohmic and saturation,and v.riations in the physical properties of the dielectric fluid with *** electric equations and the state equations based on the Boussinesq approximation are integrated in the framework of OpenFOAM buoyantBoussinesqpimpleFoam *** results show that in the ohmic regime,the combined effect of Coulomb and dielectric forces promotes the onset of RBC flow,while in the saturation state,the inhibition of RBC flow by Coulomb force is more *** v.lue of the critical rayleigh number ra decreases with increasing electric Reynolds number ReE in the ohmic regime,whereas in the saturation state,the critical ra increases with increasing *** the saturation regime,the flow field always has a steady flow in the range of parameters ***,the onset of the RBC flow promoted by the dielectric force is more pronounced in the ohmic *** to the presence of the dielectric force,the flow field exhibits periodic oscillatory flow at low electric Reynolds numbers for the range of parameters considered.

关键词： EHD conduction Dielectric force rayleigh-Bénard conv.ction OpenFOAM

pan-TRK positiv. uterine sarcoma in immunohistochemistry without neurotrophic tyrosine receptor kinase gene fusions:A case report

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World Journal of Clinical Cases 2025年第2期13卷 39-49页

作者： Seungmee Lee Yu-ra Jeon Changmin Shin Sun-Young Kwon Sojin Shin Department of Obstetrics and Gynecology Keimyung University School of MedicineDaegu 42601South Korea Department of pathology and Institute for Cancer Research Keimyung University School of MedicineDaegu 42601South Korea

BACKGROUND The classification of uterine sarcomas is based on distinctiv. morphological and immunophenotypic characteristics,increasingly supported by molecular genetic *** on neurotrophic tyrosine receptor kinase(NTRK)gene fusionpositiv. uterine sarcoma,potentially aggressiv. and morphologically similar to fibrosarcoma,are limited due to its recent ***-TRK immunohistochemistry(IHC)analysis serv.s as an effectiv. screening tool with high sensitiv.ty and specificity for NTRK-fusion *** SUMMARY We report a case of a malignant mesenchymal tumor originating from the uterine cerv.x,which was pan-TRK IHC-positiv. but lacked NTRK gene fusions,accompanied by a brief literature rev.ew.A 55-year-old woman presented to the emergency department with abdominal pain and distension,exhibiting significant ascites and multiple solid pelv.c *** examination rev.aled a tumor encompassing the uterine cerv.x,extending to the v.gina and uterine corpus.A punch biopsy of the cerv.x indicated NTRK sarcoma with positiv. immunochemical pan-TRK ***,subsequent next generation sequencing rev.aled no NTRK gene fusion,leading to a diagnosis of poorly differentiated,adv.nced-stage *** The clinical significance of NTRK gene fusion lies in potential treatment with TRK inhibitors for positiv. *** such rare tumors is crucial due to the potential applicability of tropomyosin receptor kinase inhibitor treatment.

关键词： Uterine sarcoma Cerv.cal sarcoma Neurotrophic tyrosine receptor kinase gene fusion Next generation sequencing Case report

Within-host models unrav.lling the dynamics of dengue reinfections

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Infectious Disease Modelling 2024年第2期9卷 458-473页

作者： v.zda Anam Bruno v.Guerrero Akhil Kumar Sriv.stav.Nico Stollenwerk Maíra Aguiar Basque Center for Applied Mathematics Basque CountrySpain Department of Mathematics and Statistics University of Basque CountryBasque CountrySpain Ikerbasque Basque Foundation for ScienceBasque CountrySpain

Caused by four serotypes,dengue fev.r is a major public health concern *** modeling efforts hav. mostly focused on primary and heterologous secondary infections,assuming that lifelong immunity prev.nts reinfections by the same ***,recent findings challenge this assumption,prompting a reev.luation of dengue immunity *** this study,we dev.lop a within-host modeling framework to explore different scenarios of dengue *** prev.ous studies,we go beyond a deterministic framework,considering indiv.dual immunological *** deterministic and stochastic models are calibrated using empirical data on v.ral load and antibody(IgM and IgG)concentrations for all dengue serotypes,incorporating confidence interv.ls deriv.d from stochastic *** good agreement between the mean of the stochastic realizations and the mean field solution for each model,our approach not only successfully captures primary and heterologous secondary infection dynamics facilitated by antibody-dependent enhancement(ADE)but also prov.des,for the first time,insights into homotypic reinfection *** study discusses the relev.nce of homotypic reinfections in dengue transmission at the population lev.l,highlighting potential implications for disease prev.ntion and control strategies.

关键词： infections immunity prev.ntion