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Phosphine/Benzocyclone-based neutral nickel Catalysts for Ethylene Polymerization and Copolymerization with Polar Monomers

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ch.nese Journal of Polymer Science 2024年第2期42卷 202-212,I0007页

作者： Fei Wang Li Pan Vladislav A.Tuskaev Svetlana ch.Gagieva Yue-Sheng Li Tianjin Key Lab of Composite&Functional Materials School of Material Science and EngineeringTianjin UniversityTianjin300072China Department of chemistry Lomonosov Moscow State UniversityRussian Federation InstitutionLeninskie Gory 1Moscow119991Russian Federation A n nesmeyanov Institute of Organoelement Compounds Russian Academy of SciencesVavilova st.28Moscow119991Russian Federation

The efficient copolymerization of olefin with polar monomers using nickel-based catalysts presents a longstanding challenge. In this contribution, three phosphine-benzocyclone ligands and corresponding neutral nickel catalysts(ni1: Ar = Ph;ni2: Ar = 2-(C_(6)H_(5))C_(6)H_(4);ni3: Ar = 2-[2',6'-(Me O)_(2)-C_(6)H3]C_(6)H_(4)) were prepared and applied for the ethylene polymerization and copolymerization with polar monomers without any cocatalyst. The bulky substituent groups in complexes ni2 and ni3 contributed to high catalytic activities(up to 7.24×10^(6) and 9.04×10^(6)g·mol ni^(-1)·h^(-1), respectively), and produced high-molecular-weight polyethylene(Mw up to 545.7 k Da). Complex ni3 exhibited high activities for ethylene polymerization at the level of 10^(6) g·mol ni^(-1)·h^(-1) across a wide range from 30 ℃ to 120 ℃, exhibiting excellent high temperature tolerance. These nickel complexes were also effectively employed in the copolymerization of ethylene with methyl acrylate, ethyl acrylate, butyl acrylate and lauryl acrylate, producing copolymers with high molecular weights(Mw up to 80.5 k Da) and high polar monomer incorporation(up to 8.2 mol%). Microstructure analyses revealed that the introduction of large sterically hindered substituents facilitated the incorporation of polar functional units into the polymer backbone. This study demonstrates the potential of these nickel-based catalysts for efficient copolymerization of olefin with polar monomers.

关键词： neutral nickel catalyst Ethylene polymerization Copolymerization Polar acrylate monomers

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Synthesis and characterization of La ni_xCo_(1–x)O_3: Role of microstructure on magnetic properties

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Journal of Rare Earths 2015年第3期33卷 277-281页

作者： L.chávez-Guerrero B.Medina-Lott R.F.Cienfuegos M.A.Garza-navarro R.n.Vannier A.Ringuedé M. Hinojosa M.Cassir Universidad Autónoma de nuevo León FIME. Cd. Universitaria San Nicolás de los Garza México C.P. 66450 México Laboratoired’Electrochimie et de chimie Analytique UMR 7575 CNRS Chimie Paris Tech ENSCP 11 rue Pierre et Marie Curie F-75231 Paris Cedex 05 France Centro de Innovación Investigación y Desarrollo en Ingeniería y Tecnología PIIT Monterrey México Unité de Catalyse et de chimie du Solide UMR 8181 CNRS Villeneuve d’Ascq France

Perovskite-type structures with the composition La ni x Co1–x O3（x=0.3, 0.5, 0.7） were synthesized by a modified sol-gel method. Using transitional metal elements on the lanthanum base perovskites, properties could be tuned by doping the structure. Thermogravimetric analysis（TGA） evidenced a temperature of 350 °C as the start point of the perovskite-phase formation. Scanning electron microscopy（SEM） images showed the microstructure ch.nges（grain size） of the cobalt-doped perovskite due to composition. In addition, it was shown that magnetic properties of the samples were dependent of cobalt content; experimental results pointed to the existence of disordered spins interactions, which were more evident with the decrease of cobalt content and the existence of ferromagnetic coupling among spins of the samples. These results showed the feasibility of producing a family of compounds with the desired properties, manipulating composition and therefore the microstructure.

关键词： Co-doped perovskite microstructural control modified sol-gel ferromagnetic rare earths

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The Structure of Cool Flame Fronts of Pentane, Iso-Pentane and Their Mixture

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Journal of Thermal Science 2000年第4期9卷 365-370页

作者： Z.A.Mansurov ch.K.Westbrook 等 Al－FarabiKazakhStatenationalUniversity KarasaiBatryStr.95Akmaty480012kazakhstan UniversityofCaliforniaLawrenceLivermorenationalLaboratory

An experimental study of the combustion of two isomers of n-pentane and iso-pentane in laminar cool flames has been carried out. Three flames were studied, one with n-pentane, the second with iso-pentane, and the third with an equimolar mixture of the two isomers. Particular attention has been given to the low temperature region ahead of the hot region of the flame and the cool flame chemistry occurring there. A unique experimental facility has been used to provide access to this cool flame region. Comparisons are made of the structures of the three flames, with particular attention on the different intermediate species produced and the correlations between the fuel molecule structure and the specific intermediates produced.

关键词： hydrocarbon cool names concentration profile.

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2D Pauli Equation with Hulthén Potential in the Presence of Aharonov-Bohm Effect

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Communications in Theoretical Physics 2013年第6期59卷 679-683页

作者： n.Ferkous A.Bounames Laboratory of Theoretical Physics Department of Physics University of Jijel

The 2D Pauli equation with Hulthen potential for spin-1/2 particle in the presence of Aharonov-Bohm （AB） field is solved analytically, on the assumption that an effective approximation is used for the centrifugal term. Singular and regular solutions of the problem are obtained. It is shown that the AB field lifts the degeneracy of the energy levels. The range of the flux parameter for which singular solutions are allowed is modified compared to the pure AB case. When the screening parameter vanishes, it is shown that the obtained energy spectrum becomes the same as that of the Aharonov-Bohm Coulomb problem.

关键词： Pauli equation Hulthen potential Aharonov-Bohm effect Aharonov-Bohm coulomb problem

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Diallyl sulfide protects against n-nitrosodiethylamine-induced liver tumorigenesis:Role of aldose reductase

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World Journal of Gastroenterology 2008年第40期14卷 6145-6153页

作者： Safinaz S Ibrahim noha n nassar Department of Biochemistry Faculty of PharmacyCairo University Department of Pharmacology and Toxicology Faculty of PharmacyCairo University

AIM: To evaluate the protective effect of diallyl sulfide (DAS) against n-nitrosodiethylamine (nDEA)-induced liver ***: Male Wistar rats received either nDEA or nDEA together with DAS as *** energy metabolism was assessed in terms of lactate,pyruvate,lactate/pyruvate,ATP levels,lactate dehydrogenase (LDH) and glucose-6-phosphate dehydrogenase (G6PD) *** addition,membrane disintegration of the liver cells was evaluated by measuring lipid-peroxidation products,measured as malondialdehyde (MDA); nitric oxide (nO) levels; glucose-6-phosphatase (G6Pase),catalase (CAT) and superoxide dismutase (SOD) *** DnA level,glutathione-S-transferase (GST) and cytochrome c oxidase activities were used as DnA fragmentation *** reductase (AR) activity was measured as an index for cancer cells resistant to chemotherapy and histopathological examination was performed on liver sections from different ***: nDEA significantly disturbed liver functions and most of the aforementioned *** with DAS significantly restored liver functions and hepatocellular integrity; improved parameters of energy metabolism and suppressed free-radical ***: We provide evidence that DAS exerts a protective role on liver functions and tissue integrity in face of enhanced tumorigenesis caused by nDEA,as well as improving cancer-cell sensitivity to *** is mediated through combating oxidative stress of free radicals,improving the energy metabolic state of the cell,and enhancing the activity of G6Pase,GST and AR enzymes.

关键词： n-nitrosodiethylamine Diallyl sulfide Liver cancer Energy metabolism Aldose reductase

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Finite groups whose n-maximal subgroups are σ-subnormal

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Science ch.na Mathematics 2019年第7期62卷 1355-1372页

作者： Wenbin Guo Alexander n. Skiba School of Mathematical Sciences University of Science and Technology of China Hefei 230026 China Department of Mathematics and Technologies of Programming Francisk Skorina Gomel State University Gomel 246019 Belarus

Let σ={σi | i ∈ I} be some partition of the set of all primes P. A set H of subgroups of G is said to be a complete Hall σ-set of G if every member ≠ 1 of H is a Hall σi-subgroup of G, for some i ∈ I, and H contains exactly one Hall σi-subgroup of G for every σi ∈σ(G). A subgroup H of G is said to be:σ-permutable or σ-quasinormal in G if G possesses a complete Hall σ-set H such that HAx= AxH for all A ∈ H and x ∈ G:σ-subnormal in G if there is a subgroup chain A = A0≤A1≤···≤ At = G such that either Ai-1■Ai or Ai/(Ai-1)Ai is a finite σi-group for some σi ∈σ for all i = 1,..., *** Mn n-1 n, then Mn is said to be an n-maximal subgroup of G. If each.n-maximal subgroup of G is σ-subnormal(σ-quasinormal,respectively) in G but, in the case n > 1, some(n-1)-maximal subgroup is not σ-subnormal(not σ-quasinormal,respectively) in G, we write mσ(G)= n(mσq(G)= n, respectively).In this paper, we show that the parameters mσ(G) and mσq(G) make possible to bound the σ-nilpotent length lσ(G)(see below the definitions of the terms employed), the rank r(G) and the number |π(G)| of all distinct primes dividing the order |G| of a finite soluble group G. We also give the conditions under which a finite group is σ-soluble or σ-nilpotent, and describe the structure of a finite soluble group G in the case when mσ(G)=|π(G)|. Some known results are generalized.

关键词： finite group n-maximal subgroup σ-subnormal subgroup σ-quasinormal subgroup σ-soluble group σ-nilpotent group

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Probit Analysis of Carbamate-Pesticide-Toxicity at Soil-Water Interface to n_2-Fixing Cyanobacterium Cylindrospermum sp.

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Rice science 2015年第2期22卷 89-98页

作者： Rabindra n.PADHY Shakti RATH Department of Botany BJB Autonomous College

Toxicity-data of two carbamate insecticides, carbaryl and carbofuran, and three fungicides, ziram, zineb and mancozeb with rice-field n2-fixing cyanobacterium Cylindrospermum sp., obtained by in vitro growth and at soil-water interface, were analyzed by the probit method. Growth enhancing concentration, no-observed effective concentration, minimum inhibitory concentration, the highest permissive concentration and lethal concentration100 （LCloo） were determined experimentally. The LC^o values of carbaryl, carbofuran, ziram, zineb and mancozeb in n2-fixing liquid medium were 56.2, 588.8, 0.07, 4.2 and 3.4 IJg/mL, respectively, whereas the corresponding LCloo values were 100.0, 1500.0, 0.17, 25.0 and 9.0 IJg/mL, respectively. The LC50 values of these pesticides in succession in n2-fixing agar medium were 44.7, 239.9, 0.07, 1.8 and 2.3 IJg/mL, respectively, whereas the corresponding LC100 values were 100.0, 600.0, 0.17, 10.0 and 7.0 IJg/mL, respectively. Similar results with nitrate supplemented liquid and agar media indicated that nitrate supplementation had toxicity reducing effect. The LCso and LC^oo values of toxicity in the n2-fixing liquid medium at soil-water interface were 91.2 and 200.0 IJg/mL for carbaryl, 2 317 and 6 000 pg/mL for carbofuran, 0.15 and 0.50 pg/mL for ziram, 16.4 and 50.0 pg/mL for zineb, and 7.2 and 25.0 pg/mL for mancozeb, respectively. Each LC^oo value at soil- water interface with a pesticide was significantly higher than its corresponding LCloo value at liquid/agar media. It can be concluded that, under the n2-fixing conditions, the cyanobacterium tolerated higher levels of each pesticide at soil-water interface.

关键词： carbamate pesticide Cylindrospermum sp. cyanobacterium lethal concentration probitanalysis soil-water interface

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利用激光泵浦测量传能反应Xe（^3P0,2）＋n2的绝对截面

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中国激光 1997年第10期24卷 909-914页

作者：徐大东李学初 ch.Ottinger A.F.Vilesov T.Winkler 中国科学院大连化学物理研究所分子反应动力学国家重点实验室大连116023 Max-Planck-Institut für Stroungsforsch.ng Bunsenstr

在束－气池构型下用脉冲激光泵浦技术测量了亚稳态Ｘｅ（＾３Ｐ０）和Ｘｅ（＾３Ｐ２）与Ｎ２传动用一成Ｎ２（Ｂ，ｖ）的绝对截面，并讨论了该方法在研究亚稳态原子传能及反应中的适用性。

关键词：激光泵浦亚稳态电子传能绝对截面

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nASA’s Pioneer Spacecraft Anomaly, Heat, Dark Matter and a Probable Persuasive Genesis

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Journal of High Energy Physics, Gravitation and Cosmology 2023年第4期9卷 1356-1373页

作者： Leandro Meléndez Lugo Esteban chávez Alarcón Instituto nacional de Investigaciones nucleares Centro Nuclear de M&eacutexico Ciudad de M&eacutexico M&eacutexico Departamento de Fí sica La Marquesa Ocoyoacac Ciudad de M&eacutexico M&eacutexico

An analysis is performed on what is known as the anomaly of nASA’s probe spacecraft. It explains why this additional acceleration can hardly be caused by the heat emitted by the electronic equipment of the spacecraft or by the dark matter that the Solar System could contain. Additionally, the correct stellar dynamics are mathematically demonstrated to explain the high speed of stellar rotation directly in galaxies and to show that this dynamics governing galaxies is very different from the dynamics of the Solar System. This also demonstrates the superfluity of postulating the existence of Dark Matter at the galactic level. It is concluded that the anomaly of the Pioneer spacecraft is relatively feasible as a product of an explainable difference between the modeling of the 70s and the real sources of the gravitational field of the Solar System. Therefore, it is claimed that there were sources of gravitational field that were not included in the original modeling because they were unknown at the time. Finally, a particular distribution of the disperse Solar System mass is proposed that could represent the sources of the field that give a plausible explanation for the nASA spacecraft anomaly.

关键词： Dark Matter Pioneers 10 and 11 Galactic Radial Velocity Gravitation Radiation Pressure

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Transfection of colorectal cancer cells with chemokine MCP-3(monocyte chemotactic protein-3)gene retards tumor growth and inhibits tumor metastasis

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World Journal of Gastroenterology 2002年第6期8卷 1067-1072页

作者： Jian-GaoZhu Yue-FeiLi Guo-HuaZhou Qu-BingSun Jin-YueHu Guan-ch DepartmentofInternalMedicine HunanArmedPoliceForceHospitalChangsha410006HumanProvinceChina LaboratoryofTumorImmunobiology CancerResearchInstituteXiangyaMedicalSchoolCentralSouthUniversityChangsh

AIM: To evaluate the possibility of the induction of antitumor immune response by transfecting the colorectal cancer cells with chemokine MCP-3 gene. METHODS: Mouse MCP-3 gene was transduced into mouse colorectal cancer cells CMT93 by using of Liposome. G418-resistant clones were selected and the MCP-3 mRnA expression was detected by RT-PCR. The chemotactic activity of MCP-3 in the cell culture supernatant was detected by chemotaxis assay. The tumorigenicity of wild type CMT93 and CMT93 gene transfectants were detected by in vivo experiments. The immune cell infiltrations in tumor tissue and tumor metastasis were detected ***: MCP-3 mRnA expression was detected by RTPCR in gene-transfected cells (CMT93/MCP-3), but not in control groups. And MCP-3 secreted in the cell culture supernatant possessed chemotatic activity. The results from in vivo experiments showed that the tumorigenicity of CMT93/MCP-3 had not decreased, but the tumors derived from CMT93/MCP-3 cells grew more slowly than those from CMT93 cells (1.021±0.253) cm2 VS(1.769±0.371) cm2,P＜0.05) or CMT93/mock cells (1.021±0.253) cm2 VS(1.680±0.643)cm2, P＜0.05). Histophathological results showed few immune cells infiltrating in the tumor tissue derived from the controls. In the tumor tissue derived from CMT93/MCP-3, infiltrating immune cells increased. In addition, no tumor metastasis was found in all mice inoculated with CMT93/MCP-3 tumor cells. But all mice had tumor metastasis in CMT93 controls and 4 in 5 mice had tumor metastasis in CMT93/mock ***: The results suggested that the transfection of chemokine MCP-3 gene could promote the induction of anti-colorectal cancer immunity, but the tumor growth could not be inhibited completely by merely MCP-3 gene transfection.

关键词：结直肠癌细胞趋化因子 MCP-3 基因转染肿瘤生长肿瘤转移抑制作用

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