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Application of Iron Nanoparticles Synthesized by Green Tea for the Removal of Hexavalent Chromium in Column Tests 被引量:6
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作者 C. Mystrioti A. Xenidis N. Papassiopi 《Journal of Geoscience and Environment Protection》 2014年第4期28-36,共9页
Nano zero valent iron particles (nZVI) are popular the last few years because of the numerous applications in remediation of a wide range of pollutants in contaminated soils and aquifers. The nZVI particles can be 10 ... Nano zero valent iron particles (nZVI) are popular the last few years because of the numerous applications in remediation of a wide range of pollutants in contaminated soils and aquifers. The nZVI particles can be 10 - 1000 times more reactive than granular or micro-scale ZVI particles due to the small particle size, large specific surface area and high reactivity. An alternative green synthesis procedure was used for the production of nano zero valent iron particles (nZVI) using green tea (GT) extract, which is characterized by its high antioxidant content. Polyphenols in green tea extract possess double role in the synthesis of nZVI, because they not only reduce ferric cations, but also protect nZVI from oxidation and agglomeration as capping agents. The objective of current study was to simulate ata laboratory scale the attachment of GT-nZVI particles on soil material and study the effectiveness of attached nanoparticles for removing hexavalent chromium (Cr(VI)) from contaminated groundwater flowing through the porous soil bed. Column tests were carried out with various flowrates in order to examine the effect of contact time between the attached on porous medium nZVI and the flow-through solution on Cr(VI) reduction. After the completion of column tests the soil material in each column was split in 5 vertical sections, which were further subjected to chemical analyses and leaching tests. According to the results of the study increasing the contact time favors the reduction and removal of Cr(VI) from the aqueous phase. The reductive precipitation of Cr can be described as a reaction that follows a pseudo-first order kinetic law, with rate constant equal to k = 0.0243 ± 0.0011 min-1. Leaching tests indicated that precipitated chromium is not soluble. In the examined soil material, the total amount of precipitated Cr was found to range between 280 and 890 mg/(kg soil), while soluble Cr was less than 1.4 mg/kg and most probably it was due to the presence of residual Cr(VI) solution in the porosity of soil. 展开更多
关键词 NANOSCALE Zero valent Iron NZVI Hexavalent CHROMIUM REDUCTIVE Capacity COLUMN Tests
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Safety of a 13-Valent Pneumococcal Conjugate Vaccine in Elderly Adults Previously Immunized with a 23-Valent Pneumococcal Polysaccharide Vaccine: An Open-Label Trial
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作者 Tino F. Schwarz Karlis Pauksens +4 位作者 Christine Juergens Deepthi Jayawardene Daniel A. Scott William C. Gruber Beate Schmoele-Thoma 《World Journal of Vaccines》 2013年第4期123-129,共7页
An open-label, multicenter study was conducted to describe the safety of the 13-valent pneumococcal conjugate vaccine (PCV13) in 1049 individuals aged ≥68 years, who had previously been immunized with the unconjugate... An open-label, multicenter study was conducted to describe the safety of the 13-valent pneumococcal conjugate vaccine (PCV13) in 1049 individuals aged ≥68 years, who had previously been immunized with the unconjugated 23-valent pneumococcal polysaccharide vaccine (PPSV23). In addition, the safety profile of PCV13 in this study was compared, in a post-hoc descriptive analysis, to that observed in other elderly populations, who had received PCV13 or PPSV23 as part of other completed studies. Local (56.6%) and systemic reactions (58.4%) were very common, but were mainly mild, and of short duration (mean: 1.3 - 4.6 days). There were no related serious adverse events (AEs) within 1 month after PCV13. 123 days after PCV13 and 94 days after a nonstudy influenza vaccine, a case of transient Guillain-Barré syndrome occurred, which the investigator assessed as possibly related to the vaccination. Reactogenicity observed in this study population was generally similar to that of other elderly study populations with PPSV23-preimmunized adults, and with PPSV23-naive adults. Reactogenicity was less common in this study than that observed in PPSV23-preimmunized adults who were revaccinated with PPSV23 rather than a subsequent dose of PCV13. There were no related serious AEs reported after PCV13 and PPSV23 in these comparator studies. Conclusion: PCV13 may be administered safely to older adults previously immunized with PPSV23. (ClinicalTrials. gov Identifier: NCT00500266) 展开更多
关键词 13-valent PNEUMOCOCCAL Conjugate VACCINE 23-valent PNEUMOCOCCAL Polysaccharide VACCINE Streptococcus PNEUMONIAE REACTOGENICITY SAFETY
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Degradation of nitrobenzene-containing wastewater by sequential nanoscale zero valent iron-persulfate process 被引量:2
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作者 Jingjuan Qiao Weizhou Jiao Youzhi Liu 《Green Energy & Environment》 SCIE CSCD 2021年第6期910-919,共10页
As nitrobenzene(NB)is structurally stable and difficult to degrade due to the presence of an electron withdrawing group(nitro group).The sequential nanoscale zero valent iron-persulfate(NZVI-Na_(2)S_(2)O_(8))process w... As nitrobenzene(NB)is structurally stable and difficult to degrade due to the presence of an electron withdrawing group(nitro group).The sequential nanoscale zero valent iron-persulfate(NZVI-Na_(2)S_(2)O_(8))process was proposed in this study for the degradation NB-containing wastewater.The results showed that the NB degradation efficiency and the total organic carbon removal efficiency in the sequential NZVINa_(2)S_(2)O_(8)process were 100%and 49.25%,respectively,at a NB concentration of 200 mg L^(-1),a NZVI concentration of 0.75 g L^(-1),a Na_(2)S_(2)O_(8)concentration of 26.8 mmol L^(-1),an initial pH of 5,and a reaction time of 30 min,which were higher than those(88.53%and 35.24%,respectively)obtained in the NZVI/Na_(2)S_(2)O_(8)process.Sulfate radicals(SO_(4)·-)and hydroxyl radicals(·OH)generated in the reaction were identified directly by electron paramagnetic resonance spectroscopy and indirectly by radical capture experiments,and it was shown that both SO_(4)^(·-)and·OH played a major role in the sequential NZVI-Na_(2)S_(2)O_(8)process.The possible pathways involved in the reduction of NB to aniline(AN)and the further oxidative degradation of AN were determined by gas chromatography-mass spectrometry. 展开更多
关键词 Nanoscale zero valent iron Impinging stream-rotating packed bed Sequential NZVI-Na2S2O8process NITROBENZENE Degradation pathways
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ON THE CLASS φ_p~*(α,β,γ,ε,η;A) of p-VALENT FUNCTIONS WITHREFERENCE TO THEBERNARDI INTEGRAL OPERATOR 被引量:1
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作者 蹇明 《Acta Mathematica Scientia》 SCIE CSCD 1994年第4期371-376,共6页
ONTHECLASSφ_p~*(α,β,γ,ε,η;A)ofp-VALENTFUNCTIONSWITHREFERENCETOTHEBERNARDIINTEGRALOPERATORJianMing(蹇明)(WuhanUn... ONTHECLASSφ_p~*(α,β,γ,ε,η;A)ofp-VALENTFUNCTIONSWITHREFERENCETOTHEBERNARDIINTEGRALOPERATORJianMing(蹇明)(WuhanUniversity,Wuhan430... 展开更多
关键词 CLASS OPERATOR THEBERNARDI ON FUNCTIONS INTEGRAL valent WITHREFERENCE of
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Characterization of the adsorption behavior of aqueous cadmium on nanozero-valent iron based on orthogonal experiment and surface complexation modeling 被引量:2
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作者 Dongmei Liu Huan Tang +2 位作者 Ying Zhao Fuyi Cui Jing Lu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2016年第9期1270-1274,共5页
Polyvinylpyrrolidone K-30(PVP) was introduced into the preparation of nanozero-valent iron(n ZVI) and the traditional liquid-phase reduction was improved. The introduction of PVP simplified the traditional method.The ... Polyvinylpyrrolidone K-30(PVP) was introduced into the preparation of nanozero-valent iron(n ZVI) and the traditional liquid-phase reduction was improved. The introduction of PVP simplified the traditional method.The n ZVI prepared with this new approach showed excellent surface characters and high performance on the removal of cadmium. TEM results showed that the aggregates of n ZVI can reach to several micrometers in length but less than 100 nm in diameter. The iron particles that were enclosed by a layer of oxide film that is less than10 nm, demonstrated that the n ZVI possesses a core–shell structure. BET results indicate that the specific surface area of the n ZVI was 20.3159 m^2g^(-1). A three factor and three level orthogonal experiment was employed to find out the dominant factor that affects the removal rate of cadmium by n ZVI. Based on the range values, the prominence order of each factor was: initial p H of the solution N initial concentration of cadmium N dosage of n ZVI, the range was 96.453, 3.294 and 1.747, respectively. A simulation was performed under the same condition and a same conclusion was derived, this consistence confirmed the validity of the conclusion that p H is the most significant factor that affects the adsorption efficiency. 展开更多
关键词 Nanozero-valent 合成 POLYVINYLPYRROLIDONE 直角的实验 传播层模型
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Convexity for New Integral Operator on k-uniformly p-valent α-convex Functions of Complex Order 被引量:1
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作者 LI Shu-hai MA Li-na A O-en 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第1期88-96,共9页
In this paper,we obtain the convexity of new general integral operator on some classes of fc-uniformly p-valentα-convex functions of complex order.These results extend some known theorems.
关键词 analytic functions p-valently k-uniformly STARLIKE CONVEX integral operator
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Sorption Kinetic of Arsenate as Water Contaminant on Zero Valent Iron 被引量:1
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作者 Osama Eljamal Keiko Sasaki Tsuyoshi Hirajima 《Journal of Water Resource and Protection》 2013年第6期563-567,共5页
This study investigates the sorption of arsenate from water using zero-valent iron ZVI as sorbent. Batch experiments were carried out to study the sorption kinetics of arsenate under different concentrations of arsena... This study investigates the sorption of arsenate from water using zero-valent iron ZVI as sorbent. Batch experiments were carried out to study the sorption kinetics of arsenate under different concentrations of arsenate varies from 0.5 to 200 mg/l. A kinetic model was considered to describe the arsenates sorption on ZVI material. The kinetics of the arsenate sorption processes were described by the Langmuir kinetic model. The sorption capacity increases with high initial concentration which obtained the maximum sorption 2.1 mg/g at 200 mg/l of arsenate initial concentration. The results show that the rapid initial sorption rates of arsenate were occurred at the beginning of experiments running time, followed by a slower removal that gradually approaches an equilibrium condition. The data from laboratory batch experiments were used to verify the simulation results of the kinetic model resulting in good agreement between measured and modeled results. The results indicate that ZVI could be employed as sorbent materials to enhance the sorption processes and increase the removal rate of arsenate from water. 展开更多
关键词 Arsenic SORPTION LANGMUIR KINETIC Model Zero-valent IRON Removal of ARSENATE Iron(III)
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Some Basic Properties for Certain Classes of p-valent Analytic Functions Using Differential Operator 被引量:1
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作者 ZHANG Hai- Yan TANG Huo +1 位作者 LI Shu-Hai MA Li-Na 《Chinese Quarterly Journal of Mathematics》 2018年第2期132-139,共8页
In this paper, we introduce new subclasses of p-valent analytic functions defined by using differential operator in the open unit disc. We study coefficient inequality, distortion theorem, radius of close to-convexity... In this paper, we introduce new subclasses of p-valent analytic functions defined by using differential operator in the open unit disc. We study coefficient inequality, distortion theorem, radius of close to-convexity, starlikeness and convexity, extreme points and integral operator for functions in these new subclasses. 展开更多
关键词 p-valent functions Differential operator Coefficient inequality Distortion theorem RADIUS
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Substitution Process and Valent State of Samarium Ion in Perovskite Binary Fluorides
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作者 曾志成 石春山 倪嘉缵 《Journal of Rare Earths》 SCIE EI CAS CSCD 1993年第2期98-101,共4页
The lattice sites occupied by samarmm ions in KMgF<sub>3</sub> were ascertained The relationship be-tween valent state of samarium ion in hosts and substituted lattice sites was mvestigated using fluoresce... The lattice sites occupied by samarmm ions in KMgF<sub>3</sub> were ascertained The relationship be-tween valent state of samarium ion in hosts and substituted lattice sites was mvestigated using fluorescentspectra.It is found that the valent state of samarium in different cationic lattice sites is different The internalrelation between the valent state of samarium ion and occupied lattice site was 展开更多
关键词 Fluorescent spectrum valent STATE of SAMARIUM ion Substituted lattice site PEROVSKITE BINARY FLUORIDE
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LOW-VALENT TITANIUM INDUCED REDUCTIVE COUPLING OF AROMATIC NTTRILES TO 1,2-ARYLETHANONES
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作者 Wei Xing CHEN*, Jian Xie CHEN, Jian Ping JIANG, Tsi Yu KAO (Department of Chemistry,Nanjing University,Nanjing,210008) 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第5期351-352,共2页
Reductive coupling of aromatic nitriles 1 by titanium tetrachloride/zinc provides an efficient general synthesis of 1,2-arylethanones.
关键词 TETRACHLORIDE TITANIUM AROMATIC valent SUBSTITUTED anone NITRILE PENSION Astron distilled
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THE INTRAMOLECULAR COUPLING REACTION OF 2-NITROETHYL-1, 3-DICARBONYL COMPOUND INDUCED BY LOW-VALENT TITANIUM
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作者 Ju GAO~*, Jian Ping JIANG, Jian Xie CHEN, Su YUAN, Xiao Man ZHANG, Wei Xing CHEN Department of Chemistry, Nanjing University, Nanjing, 210008 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第1期17-18,共2页
Low-valent titanium reagent prepared in situ from TiCl<sub>4</sub> and Zn was employed to induce the intramolecular coupling of nitro group with carbonyl group to give substituted hydroxyl pyrrolines, pyrr... Low-valent titanium reagent prepared in situ from TiCl<sub>4</sub> and Zn was employed to induce the intramolecular coupling of nitro group with carbonyl group to give substituted hydroxyl pyrrolines, pyrroles and lactam in good yields. 展开更多
关键词 INTRAMOLECULAR CARBONYL reagent substituted hydroxyl titanium valent LACTAM NITRO CHLOROFORM
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LOW-VALENT TITANIUM INDUCED REDUCTIVE REACTION OF THIOCYANATES AND ISOCYANATE
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作者 Jian Xie CHEN, Da Qing SHI, Wen Ying CHAI, Jian CHEN, Wei Xing CHEN, Tsi Yu KAO Department of Chemistry, Nanjing University, Nanjing, 210008 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第11期943-946,共4页
Low-valent titanium reagent prepared from titanium tetrachloride and zinc was empolyed to induce the coupling reaction of thiocyanates with tetrahydrofuran yield alkyl 4-hydroxy butyl sulfide and isocyanate yield subs... Low-valent titanium reagent prepared from titanium tetrachloride and zinc was empolyed to induce the coupling reaction of thiocyanates with tetrahydrofuran yield alkyl 4-hydroxy butyl sulfide and isocyanate yield substituted urea. 展开更多
关键词 alkyl TETRACHLORIDE titanium reagent substituted valent sulfide BUTYL BENZYL tetrahydro
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MECHANISM FOR THE EFFECTS OF MONO-VALENT CATIONS ON ^(23)Na NMR
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作者 Zhe ZHOU~*, Rong Juan CONG, Dong Hai LIN, Weng Xiu WANG, Qin Yi WU Department of Chemistry, Xiamen University, Xiamen 361005 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第5期459-462,共4页
The effects of mono-valent cations, Li<sup>+</sup>, K<sup>+</sup>, Rb<sup>+</sup>, Cs<sup>+</sup> and NH<sub>4</sub><sup>+</sup>, on <sup>2... The effects of mono-valent cations, Li<sup>+</sup>, K<sup>+</sup>, Rb<sup>+</sup>, Cs<sup>+</sup> and NH<sub>4</sub><sup>+</sup>, on <sup>23</sup>Na NMR were investigated. It was found that the chemical shifts for Na<sup>+</sup> signal shifted downfield with the increase in the relative amounts of monovalent cations. It was suggested that mono-valent cations had competition coordination with Na<sup>+</sup> for Dy(PPP)<sub>2</sub><sup>7-</sup>. 展开更多
关键词 valent COMPETITION shifted Becker Gupta Fujian enabled STAND THANKS
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LOW-VALENT TITANIUM INDUCED REDUCTIVE CROSS-COUPLING REACTION OF ACYL CHLORIDES WITH DIARYL KETONES
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作者 Da Qing SHI Department of Chemistry,Xuzhou Teachers Collegs Xuzhou 221009Wei Xing CHEN Department of Chemistry,Nanjing University,Nanjing 210008 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第8期681-682,共2页
Treatment of acyl chlorides and diaryl ketones with anactivated Ti(o)reagent,prepared by reduction of TiCl<sub>4</sub> with Znpowder,effects an intermolecular reductive cross-coupling reactionleading to ... Treatment of acyl chlorides and diaryl ketones with anactivated Ti(o)reagent,prepared by reduction of TiCl<sub>4</sub> with Znpowder,effects an intermolecular reductive cross-coupling reactionleading to ketones. 展开更多
关键词 INTERMOLECULAR REAGENT REDUCTIVE valent titanium tempera SLURRY Schultz ARGON DRIED
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Remediation of Malathion Contaminated Soil Using Zero Valent Iron Nano-Particles
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作者 R. K. Singhal B. Gangadhar +3 位作者 H. Basu V. Manisha G.R. K. Naidu A.V. R. Reddy 《American Journal of Analytical Chemistry》 2012年第1期76-82,共7页
In this study, iron nano-particles were used to remediate malathion contaminated soil in the concentration range of 1 - 10 μg?g–1. The zero valent iron nano-particles were prepared by reducing ferric chloride soluti... In this study, iron nano-particles were used to remediate malathion contaminated soil in the concentration range of 1 - 10 μg?g–1. The zero valent iron nano-particles were prepared by reducing ferric chloride solution with sodium boro- hydride for remediation of the soil. The optimized quantity of iron nano particles was found to be 0.1 g?kg–1 of soil con- taminated with 10 μg?g–1 of malathion. Malathion was determined in the soil after leaching to water at pH 8.2 and fol- lowed by its oxidation with slight excess of N-bromosuccinimide (NBS). The unconsumed NBS was estimated by measuring the decrease in the color intensity of rhodamine B. Degradation product formed during the oxidation of ma-lathion by zero valent iron was monitored by the Attenuated Total Reflectance Fourier Transform Infrared Spectros- copy (ATR-FTIR). The results clearly showed that quantitative oxidation of malathion was achieved within eight min- utes after the addition of zero valent iron nano particles. 展开更多
关键词 MALATHION ZERO valent Iron Nano Particle Soil CONTAMINATION
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Evaluating Effectiveness and Permanence of Selenium Treatment in a Solid Matrix via Aqueous-Mediated Zero Valent Iron Reaction
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作者 Scott A. Grieco Danielle C. Singer Gary R. Bement 《Journal of Environmental Protection》 2017年第9期990-1001,共12页
Increasingly, as regulatory limits become more stringent, selenium has become a parameter of concern. Selenium is a naturally occurring element that is largely mobilized by anthropogenic activity such as mining for fu... Increasingly, as regulatory limits become more stringent, selenium has become a parameter of concern. Selenium is a naturally occurring element that is largely mobilized by anthropogenic activity such as mining for fuel and subsequent combustion, metal ore refining and processing, and agricultural irrigation. Of concern is removing selenium liquid matrices and immobilizing it from leachable solid matrices. Chemical reduction and stabilization using zero valent iron (ZVI) is applicable to both concerns. The solid matrix case study is applicable to ash ponds solids or industrial bag house dust solids. This paper presents data for treatment and stabilization of selenium within a solid matrix using ZVI. The methodology uses an aqueous mediate reaction to promote a stable solid matrix of non-leachable selenium. The paper describes matrix challenges and key variables that effected successful treatment. Testing with simulated and real bag house dust solids were used to establish data to support the permeance of the reaction. The data show that ZVI converts ionic selenium to a zero valent state in the solid matrix. It was also recognized that a fraction of ionic selenium may fail to react with the ZVI, but the results show that despite the presence of the unreacted ionic selenium, the toxicity characteristic leachate procedure (TCLP) results following treatment do not exceed the 1 mg/L hazardous waste criteria. 展开更多
关键词 BAG House Dust SELENIUM Chemical Reduction Land DISPOSAL Restrictions Toxicity Characteristic LEACHING Procedure TCLP Zero valent Iron
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Coefficient Inequalities for p-Valent Functions
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作者 T.Panigrahi R.N.Mohapatra 《Analysis in Theory and Applications》 CSCD 2018年第2期112-126,共15页
In the present paper, the authors introduce a new subclass of p-valent analytic functions with complex order defined on the open unit disk U={z:z∈C and |z|<1} and obtain coefficient inequalities for the functions ... In the present paper, the authors introduce a new subclass of p-valent analytic functions with complex order defined on the open unit disk U={z:z∈C and |z|<1} and obtain coefficient inequalities for the functions in these class. Application of these results for the functions defined by the convolution are also obtained. 展开更多
关键词 P-valent function SUBORDINATION COEFFICIENT INEQUALITIES CONVOLUTION
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On Certain Classes of p-Valent Functions
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作者 M. K. AOUF (Dept. of Math. Faculty of Science Univ. of Mansoura,Mansoura,Egypt) 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 1994年第2期1-5,共5页
OnCertainClassesofp-ValentFunctions¥M.K.AOUF(Dept.ofMath.FacultyofScienceUniv.ofMansoura,Mansoura,Egypt)Abst... OnCertainClassesofp-ValentFunctions¥M.K.AOUF(Dept.ofMath.FacultyofScienceUniv.ofMansoura,Mansoura,Egypt)Abstract:Therearemany... 展开更多
关键词 ss: ANALYTIC P-valent STARLIKE COEFFICIENT
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Fekete-Szego Problem for Certain Subclass ofp-Valent Analytic Functions usingQuasi-Subordination
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作者 AO En LI Shu-hai +1 位作者 TANG Huo Siqinqimuge 《Chinese Quarterly Journal of Mathematics》 2017年第4期432-440,共9页
n this paper, a new certain class of p-valent analytic functions with quasi-subordination is defined and the Fekete-Szeg5 problems for functions belonging to the classare derived. The results presented here provide ex... n this paper, a new certain class of p-valent analytic functions with quasi-subordination is defined and the Fekete-Szeg5 problems for functions belonging to the classare derived. The results presented here provide extensions of those given in some earlierworks. 展开更多
关键词 analytic FUNCTIONS P-valent FUNCTIONS quasi-subordination FEKETE-SZEGO prob-lem.
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9-Valent疫苗或对预防宫颈癌有成效
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《临床合理用药杂志》 2015年第14期103-103,共1页
美国的一项新研究表明,在儿童12岁之前给他们注射最新的人乳头瘤病毒(HPV)疫苗能有80%的概率预防宫颈癌。本研究旨在确定人类乳头状瘤病毒(HPV)相关的癌症在美国的prevaccine特定类型的发生率。研究表明,该疫苗(被称为9-Valent)... 美国的一项新研究表明,在儿童12岁之前给他们注射最新的人乳头瘤病毒(HPV)疫苗能有80%的概率预防宫颈癌。本研究旨在确定人类乳头状瘤病毒(HPV)相关的癌症在美国的prevaccine特定类型的发生率。研究表明,该疫苗(被称为9-Valent)能预防9中不同的人乳头瘤病毒株,同时也可能能预防19,000种其他癌症,包括肛门癌和阴茎癌。 展开更多
关键词 valent 人乳头瘤病毒 阴茎癌 肛门癌 咽喉癌 特定类型 口咽癌 资讯网 Goodman 口交
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