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面向实时操作系统μC/OS-II的两级优先调度算法
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作者 李启明 杨霞 +1 位作者 房文宇 孙海泳 《计算机与现代化》 2024年第6期33-37,共5页
C/OS-II采用抢占式优先级调度算法,根据任务的重要程度分配不同的优先级,以确保系统的实时性。但μC/OSII不允许多个任务具有相同优先级,不仅限制了并发任务的数量和灵活性,而且在某些情况下会增加系统的复杂度,甚至可能给系统的运行造... C/OS-II采用抢占式优先级调度算法,根据任务的重要程度分配不同的优先级,以确保系统的实时性。但μC/OSII不允许多个任务具有相同优先级,不仅限制了并发任务的数量和灵活性,而且在某些情况下会增加系统的复杂度,甚至可能给系统的运行造成安全隐患。本文通过改进μC/OS-II的优先级位图结构与调度算法,为μC/OS-II扩展了2级优先调度机制。改进后的系统允许用户为多个任务赋予相同的优先级,同一优先级下的任务按照二级优先级进行调度,且可以根据实际需要灵活选择二级调度策略。实验表明,该算法可有效提高μC/OS-II的并发能力和资源利用率,同时保持较低的系统开销和响应时间。 展开更多
关键词 实时操作系统 ΜC/os-ii 优先级调度算法 实时性
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基于μC/OS-II的GPRS远程监控系统设计
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作者 蔡旭 《传感器世界》 2024年第3期19-26,共8页
随着信息技术和数字技术的迅猛发展,通信技术在宽带通信网络和无线通信领域取得了巨大突破。这些技术的进步为各个行业带来彻底变革的机会,其中包括无线监控系统。文章以无线监控系统中实际案例为设计对象,旨在通过结合GPRS模块和单片... 随着信息技术和数字技术的迅猛发展,通信技术在宽带通信网络和无线通信领域取得了巨大突破。这些技术的进步为各个行业带来彻底变革的机会,其中包括无线监控系统。文章以无线监控系统中实际案例为设计对象,旨在通过结合GPRS模块和单片机实现该无线监控系统的功能需求。系统采用模块化管理的策略,以确保系统高效运行。通过将各个部件模块化设计,有效进行数据采集,及时响应不同的指令,并按照任务工作安排执行相应工作,提升系统的效率和可扩展性,为后续发展提供了便利。系统实现嵌入式远程监控系统的各种功能,系统终端根据功能需求分类,为操作者提供了简洁易懂的人机交互界面,方便操作者下达指令,快捷实用。 展开更多
关键词 ΜC/os-ii GPRS 远程监控
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Preparation of Platinum(II) Complexes with 1-β-D-Ribofuranosyl-1,2,4-triazole-3-carboxamide and its Deoxy-analogue 被引量:7
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作者 Wen PEI Kobe JOZE 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第6期559-562,共4页
The platinum (II) complexes of the [Pt (N4,N7-Ribavirin) (DMSO) Cl], [Pt (N4,N7-De-oxyribavirin) (DMSO) Cl] were obtained by the reactions of cis-[Pt (DMSO)2 Cl2] and K[Pt (DMSO) Cl3] with 1-??-D-ribofuranosyl-1,2,4-t... The platinum (II) complexes of the [Pt (N4,N7-Ribavirin) (DMSO) Cl], [Pt (N4,N7-De-oxyribavirin) (DMSO) Cl] were obtained by the reactions of cis-[Pt (DMSO)2 Cl2] and K[Pt (DMSO) Cl3] with 1-??-D-ribofuranosyl-1,2,4-triazole-3-carboxamide (Ribavirin) and its deoxy-analogue (deoxyribavirin). The preparation of 1-(2'-deoxy-?-D-ribofuranosyl) -1,2,4-triazole-3-carboxamide was also performed through a four-step procedure, protection of 3', 5'-dihydroxyl group of Ribavirin with 1,3-dichloro-1,1,3,3-tetraisopropyldisiloxane (TPDS-Cl), phenoxythio-carbonylation of the 2'-hydroxyl group of 3', 5'-O-TPDS-Ribavirin with phenoxythiocarbonyl-chloride (PTC-Cl), reduction of 2′-O-phenoxythiocarbonyl ester of 3', 5'-O-TPDS-Ribavirin with tri-n-butyltin hydride and AIBN, deprotection of 3', 5'-O-TPDS-Ribavirin with tetrabutylammon-ium fluoride in THF. 展开更多
关键词 Platinum(ii) complexes ribavirin and deoxyribavirin nucleobase platination complexation reaction antitumor agents
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THE CHIRAL SELECTIVITY IN ACROSS-MEMBRANE TRANSPORT OF 1,2-DIAMINOCYCLOHEXANE PLATINUM(II)COMPLEXES AND THE CONTRIBUTION OF LEAVING GROUPS
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作者 Juan ZOU Xiao Cai YANG +2 位作者 Gang LIU Rong Chang LI Kui WANG(State Key Laboratory of Coordination Chemistry, Coordination Chemistry Institute,Nanjing University,Nanjing 210093)(Inorganic Chemistry DePartment, School of Pharmaceutical Sciences,Beijing Medical 《Chinese Chemical Letters》 SCIE CAS CSCD 1996年第7期657-658,689+660,共4页
The uptake kinetics of platinum(II)complexes of 1,2 -diaminocyclohexane(dach)isomers(1R,2R-dach, 1R,2S-dach. 1S,2S-dach) with various leaving groups, Chloride(CI), oxalate (OX),squaric acid(SA), and demethylcantharic ... The uptake kinetics of platinum(II)complexes of 1,2 -diaminocyclohexane(dach)isomers(1R,2R-dach, 1R,2S-dach. 1S,2S-dach) with various leaving groups, Chloride(CI), oxalate (OX),squaric acid(SA), and demethylcantharic acid (DA) was studied in the plasma isotonic buffer. The experimentalresults show that across-membrane transport of all the platinum complexes studied follows a firstorder Kinetic process and a passive diffustion mechanism. The uptake rate constants of these platinum(II)complexes decrease in the following sequence with the k value(h-1):CI>SA>OX>DA. It isnoteworthy that the k values of the platinum(II)complexes with same leaving group reduce as: 1R,2R-dach>1R,2S-dach>1S,2S-dach. Based on these results, it is firstly suggested that the erythocytemembrane recognizes the chirality of these platinum complexes. 展开更多
关键词 ii complexes PLATINUM DIAMINOCYCLOHEXANE AND ACRosS
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Magnetic analyses of isosceles tricobalt(II) complexes containing two types of octahedral high-spin cobalt(II) ions
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作者 Hiroshi Sakiyama Harry Adams +3 位作者 David E. Fenton Laura R. Cummings Paul E. McHugh Hisashi Okawa 《Open Journal of Inorganic Chemistry》 2011年第3期33-38,共6页
The observed magnetic data for two isosceles tricobalt(II) complexes have been successfully analyzed, considering the axial distortion around each cobalt(II) ion, the local spin-orbit coupling, the anisotropic exchang... The observed magnetic data for two isosceles tricobalt(II) complexes have been successfully analyzed, considering the axial distortion around each cobalt(II) ion, the local spin-orbit coupling, the anisotropic exchange interactions, and the intermolecular exchange interactions. The complexes each contains two types of octahedral high-spin cobalt(II) ions (CoA and CoB) in the shape of an isosceles triangle (CoA1–CoB–CoA2), and the contribution of the orbital angular momentum is significant. The exchange interaction between the CoA and CoB ions is practically negligible (J = ~ 0), whereas the interaction between the CoA1 and CoA2 ions is ferromagnetic (J’ > 0) for both complexes. 展开更多
关键词 Tricobalt(ii) complex MAGNETIC Properties SPIN-ORBIT Coupling Exchange Interaction
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Kinetic parameters and thermal decomposition for Novel 1,1-Malonyl-bis(4-p-Chlorophenylthiosemicarbazide) and Cu(II), Co(II), Zn(II) and Sn(II) complexes(H<sub>4</sub>pClMaTS) synthesized by electrochemical method
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作者 Ragab R. Amin Yamany B. Yamany +1 位作者 Mohamed Abo-Aly Ali M. Hassan 《Natural Science》 2011年第9期783-794,共12页
Anodic oxidation of Co, Cu, Zn, and Sn metals in an acetone solution of 1,1-malonayl-bis(4-p- Chlorophenylthiosemicarbazide) yields complexes of composition with general formula [Co2(pClMaTS)(H2O)6]·2H2O, [Cu2(pC... Anodic oxidation of Co, Cu, Zn, and Sn metals in an acetone solution of 1,1-malonayl-bis(4-p- Chlorophenylthiosemicarbazide) yields complexes of composition with general formula [Co2(pClMaTS)(H2O)6]·2H2O, [Cu2(pClMaTS)(H2O)6], [Zn2(pClMaTS)(H2O)6] and [Sn2(pClMaTS)(H2O)6]·2H2O. Chelation was investigated based on elemental analysis, conductivity, magnetic moment, spectral (UV-Vis, IR, Raman, 1HNMR, mass), thermal, and ESR studies. The Raman and infrared spectral studies suggests the tridentate behavior of the ligand from each tail. Since the ligand has two thiose- micarbazide groups, it may acts in an SNO tridentate fashion from each side with one of the two metal ions forming a polynuclear complex coordinating through both of the lone pair of electrons the enolic oxygen of the carbonyl group (C=O), the azomethine nitrogen (C=N) and the thioenol form of the thiocarbonyl group (C=S). The differential thermogravimetric analysis (DTG) curves were used to study the decomposition steps of the isolated complexes using Horowitz-Metzger (HM) and Coats-Redfern (CR) methods. The kinetic thermodynamic parameters such as: E*, ΔH*, ΔS*and ΔG* are calculated from the DTG curves. 展开更多
关键词 Metal(ii) complexes Electrochemical THERMOGRAVIMETRIC Bis-Thiosemicarbazide
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α-Glucosidase Inhibition by New Schiff Base Complexes of Zn(II)
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作者 Rie Miyazaki Hiroyuki Yasui Yutaka Yoshikawa 《Open Journal of Inorganic Chemistry》 2016年第2期114-124,共11页
There are many reports that divalent alkaline earth, first-row transition metals, and Zn(II) ions have α-glucosidase inhibitory effects. Cu(II) and Zn(II) ions, in particular, have strong α-glucosidase inhibitory ef... There are many reports that divalent alkaline earth, first-row transition metals, and Zn(II) ions have α-glucosidase inhibitory effects. Cu(II) and Zn(II) ions, in particular, have strong α-glucosidase inhibitory effects. Several Schiff bases also display α-glucosidase inhibitory effects. In this study, we focused on safe and highly effective complexes including Zn(II) ion. We prepared and characterized the Zn(II) complexes with four different Schiff bases (N-salicylidene-β-alanine (N-sβ), N-N’-bis (salicylidene) ethylenediamine (N-bsE), N, N’-bis (salicylidene)-phenylenediamine (N-bsP), and 1-[(2-dimethylaminoethylimino) methyl]naphtholate (DMN)) and investigated their α-glucosidase inhibitory effects in vitro, using α-glycosidases from Saccharomyces sp. and rat small intestine, and in vivo, using a sucrose tolerance test. The Zn(II) complexes with DMN showed the highest in vitro and in vivo α-glucosidase inhibitory effects in this study. 展开更多
关键词 α-Glucosidase Inhibitory Effect Zn(ii) complexes Schiff Bases Diabetes Mellitus
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Theoretical Studies on Structures and Spectroscopic Properties of Highly Efficient Phosphorescent [Ru(terpy)(phen)X]+ Complexes
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作者 金丽 张建坡 +1 位作者 张红星 白福全 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2011年第4期391-398,I0003,共9页
The ground and the lowest-lying triplet excited state geometries, electronic structures, and spectroscopic properties of three mixed-ligand Ru(II) complexes [Ru(terpy)(phen)X]+ (terpy=2,2',6',2″-terpyridine... The ground and the lowest-lying triplet excited state geometries, electronic structures, and spectroscopic properties of three mixed-ligand Ru(II) complexes [Ru(terpy)(phen)X]+ (terpy=2,2',6',2″-terpyridine, phen=l,10-phenanthroline, and X=-C-=CH (1), X=Cl (2), X-CN (3)) were investigated theoretically using the density functional theory method. The ground and excited state geometries have been fully optimized at the B3LYP/LanL2DZ and UB3LYP/LanL2DZ levels, respectively. The absorption and emission spectra of the com- plexes in CHaCN solutions were calculated by time-dependent density functional theory with the PCM solvent model. The calculated bond lengths of Ru-C, Ru-N, and Ru-Cl in the ground state agree well with the corresponding experimental results. The highest occupied molecular orbital were dominantly localized on the Ru atom and monodentate X ligand for 1 and 2, Ru atom and terpy ligand for a, while the lowest unoccupied molecular orbital were π*(terpy) type orbital. Therefore, the lowest-energy absorptions of 1 and 2 at 688 and 631 nln are attributed to a dyz (Ru)+Tr/p(X)--π* (terpy) transition with MLCT/XLCT (metal-to-ligand charge transfer/X ligand to terpy ligand charge transfer) character, whereas that of 3 at 529 nm is related to a dyz (Ru)+π(terpy)-π* (terpy) transition with MLCT and ILCT transition character. The calculated phosphorescence of three complexes at 1011 nm (1), 913 nm (2), and 838 nm (3) have similar transition properties to that of the lowest-lying absorption. It is shown that the lowest lying absorptions and emissions transition character of these Ru(II) complexes can be tuned by changing the electron-withdrawing ability of the monodentate ligand. 展开更多
关键词 Mixed-ligand Ru(ii complexes Electronic structure Spectroscopic property DFT calculation UB3LYP method
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Interactions Between Anticancer Pt(II) complexes and Human Erythrocyte Spectrin *
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作者 杨晓改 李荣昌 《Journal of Chinese Pharmaceutical Sciences》 CAS 1998年第3期9-14,共6页
The interactions between human erythrocyte spectrin(SP) and Pt(II) complexes with different composition and configuration were studied by fluorescence and circular dichroism spectra. The results showed that there are ... The interactions between human erythrocyte spectrin(SP) and Pt(II) complexes with different composition and configuration were studied by fluorescence and circular dichroism spectra. The results showed that there are 4.7×10 2 binding sites of cisplatin(CDDP) in a spectrin tetramer(SPT). Among them, about 70 sites with apparent binding constant K 1】3.47×10 6 were of highest affinity, 1.8×10 2 sites with K 2 = 3.47×10 6 were of high affinity, and other 2.2×10 2 sites with K 3 = 8.77×10 5 were of low affinity. The conformation change of spectrin, depending on the concentration of Pt(II) complex and molar ratio(R) of Pt(II) complex to spectrin, was induced by the binding of Pt(II) complexes. It indicated that the interaction of both CDDP and cis diaquodiamine platinum(DADP) with SP followed a two step first order kinetic process in the first stage (1 h), and the kinetic constants were determined. In the second stage, the induced conformation change, polymerization and depolymerization of SP were probably involved. It was noticed that in the reaction of SP and Pt(II) complexes with 1,2 cyclohexanediammine isomers as chiral carrier ligand, stereo matching played a more important role than the affinity of Pt(II) to thiol groups of SP. 展开更多
关键词 Pt (ii) complex SPECTRIN CONFORMATION Binding sites Kinetic CHIRAL
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Dioxygen Affinity and Catalytic Performance of Bis-(furaldehyde) Schiff Bases Co(II) Complexes in Cyclohexene Oxidation 被引量:4
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作者 Sun, B Chen, JR +1 位作者 Hu, JY Li, XJ 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第11期1043-1046,共4页
Oxygenation constants and thermodynamic parameters DeltaH degrees and DeltaS degrees of cobalt (II) complexes with bis-(furaldehyde) Schiff bases (1, 2, 3, 4)were obtained by mearsuring saturated dioxygen uptake of th... Oxygenation constants and thermodynamic parameters DeltaH degrees and DeltaS degrees of cobalt (II) complexes with bis-(furaldehyde) Schiff bases (1, 2, 3, 4)were obtained by mearsuring saturated dioxygen uptake of these complexes in pyridine at different temperature. These complexes could activate molecular oxygen and were used as catalysts in cyclohexene oxidation. The influence of ligand structure on the dioxygen affinity and catalytic activity of the complexes were discussed. 展开更多
关键词 Schiff base cobalt (ii) complex OXYGENATION catalytic oxidation CYCLOHEXENE
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Catalytic hydrolysis of phosphate diester (BNPP) and plasmid DNA by mononuclear macrocyclic polyamine metal complexes 被引量:3
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作者 Qing Xiang Xiang Li Qun Zhang +1 位作者 Xiao Qi Yu Ru Gang Xie 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第5期523-526,共4页
The activities of the catalytic hydrolysis of phosphate diester (BNPP) [bis(p-nitrophenyl)phosphate diester] and plasmid DNA (pUC 18) by mononuclear macrocyclic polyamine metal complexes have been investigated i... The activities of the catalytic hydrolysis of phosphate diester (BNPP) [bis(p-nitrophenyl)phosphate diester] and plasmid DNA (pUC 18) by mononuclear macrocyclic polyamine metal complexes have been investigated in this paper. The results showed that the highest activity in hydrolysis of BNPP was obtained with le--Zn(II) complex (composed of lipophilic group) as catalyst. The hydrolysis rate enhancement is up to 3.64 × 10^4 fold. These metal complexes could effectively promote the cleavage of plasmid DNA (pUC18) at physiological conditions. 展开更多
关键词 Catalytic hydrolysis Macrocyclic polyamine Zn(ii complex BNPP Plasmid DNA
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Synthesis and Characterization of Chiral Mercury(II) and Cadmium(II) Complexes with 3,3'-Bipyridine-5,5',6,6'-tetramethyl-2,2'-dimethoxy-1,1'-biphenyl 被引量:1
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作者 方煜 宣为民 +2 位作者 朱成峰 袁国赞 崔勇 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第8期1147-1153,共7页
Two homochiral mercury (1) and cadmium (2) complexes derived from chiral twisted biphenyl pyridine ligand (3,3'-bipyridine-5,5',6,6'-tetramethyl-2,2'-dimethoxy-1,1'-biphenyl) have been synthesized and chara... Two homochiral mercury (1) and cadmium (2) complexes derived from chiral twisted biphenyl pyridine ligand (3,3'-bipyridine-5,5',6,6'-tetramethyl-2,2'-dimethoxy-1,1'-biphenyl) have been synthesized and characterized by IR, microanalysis, TGA, UV-Vis, powder and single-crystal X-ray crystallography. Both 1 and 2 crystallize in orthorhombic space group P21212 with Z = 2. For 1, a = 14.2038(16), b = 14.3630(17), c = 7.0257(8), V = 1433.3(3)3, Mr = 878.91, Dc = 2.037 g/cm3, μ = 7.549 mm-1, F(000) = 824, the final GOF = 1.017, R = 0.0296 and wR = 0.0645 for 2925 observed reflections with I 2σ(I). For 2, a = 14.212(3), b = 14.392(3), c = 7.0498(14), V = 1442.0(5)3, Mr = 790.72, Dc = 1.821 g/cm3, μ = 2.924 mm–1, F(000) = 760, the final GOF = 1.075, R = 0.0340 and wR = 0.0834 for 3144 observed reflections with I 2σ(I). The crystal structures of 1 and 2 are isostructural and each adopts a two-dimensional supramolecular network which contains the C–H···π interactions. 展开更多
关键词 crystal structure chiral complex mercury(ii complex cadmium(ii complex
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Preparation, Characterization and Antimicrobial Studies of Mn(II) and Fe(II) Complexes with Schiff Base Ligand Derived from 2-aminophenol and 3-formyl-2-hydroxy-6-methoxyquinoline 被引量:1
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作者 Abubakar Muhammad Jabbi Habu Nuhu Aliyu +1 位作者 Sulaiman Isyaku Abdullahi Muhammad Kabir 《Open Journal of Inorganic Chemistry》 2020年第2期15-24,共10页
Schiff base derived from 2-aminophenol and 3-formyl-2-hydroxy-6-methoxyquinoline and its Mn(II) and Fe(II) complexes were synthesized and characterized by melting point and decomposition temperature, elemental analysi... Schiff base derived from 2-aminophenol and 3-formyl-2-hydroxy-6-methoxyquinoline and its Mn(II) and Fe(II) complexes were synthesized and characterized by melting point and decomposition temperature, elemental analysis, molar conductivity, infrared (IR) spectral analysis, atomic absorption spectroscopy (AAS) analysis, solubility test, and magnetic susceptibility. The Fourier-transform infrared spectroscopy (FTIR) spectral data of the Schiff base determined showed <span><span style="font-family:Verdana;">a band at 1622 cm</span><sup><span style="font-family:Verdana;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">&#8722;</span></span></span>1</span></sup><span style="font-family:Verdana;"> and this was assigned to the </span><i><span style="font-family:Verdana;">v </span></i><span style="font-family:Verdana;">(C=N), which is a feature of azomethine group. The same band was observed to shift to lower frequencies 1577 and 1599 cm</span><sup><span style="font-family:Verdana;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">&#8722;</span></span></span>1</span></sup><span style="font-family:Verdana;"> in the complexes suggesting coordination of the Schiff base with the respective metal(II) ions. Molar conductan</span></span><span><span style="font-family:Verdana;">ce values 14.58 and 12.65 Ω</span><sup><span style="font-family:Verdana;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">&#8722;</span></span></span>1</span></sup><span style="font-family:Verdana;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">&#8729;</span></span></span>cm</span><sup><span style="font-family:Verdana;">2</span></sup><span style="font-family:Verdana;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">&#8729;</span></span></span>mol</span><sup><span style="font-family:Verdana;"><span style="white-space:nowrap;"><span style="white-space:nowrap;"><span style="white-space:nowrap;">&#8722;</span></span></span>1</span></sup><span style="font-family:Verdana;"> show that the metal complexes were non-electrolyte in nature. The magnetic susceptibility of the complexes was determined and the gram magnetic susceptibility of the complexes was found to be positive, revealing that they are paramagnetic. The elemental analysis of the complexes for C, N and H determined suggested 1:1 metal to ligand ratio. The result of the antimicrobial studies showed that, the metal(II) complexes exhibited better antibacterial and antifungal activity than the Schiff base.</span></span> 展开更多
关键词 Metal(ii) complexes Schiff Base Antibacterial and Antifungal Studies
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Comparative Studies of Some Novel Cu(II) Polymeric Complexes Derived from Cyanoacetylhydrazine (CAH;L). The Role of Solvents Used on the Structure and Geometry of the Isolated Cu<sup>2+</sup>Complexes 被引量:1
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作者 Mohsen M. Mostafa 《Open Journal of Inorganic Chemistry》 2021年第4期111-130,共20页
Novel polymeric Cu<sup>2+</sup> complexes derived from the reaction of cyanoacetylhydrazine (<strong>CAH</strong>;<strong>L</strong>) with CuCl<sub>2</sub>•2H<sub>... Novel polymeric Cu<sup>2+</sup> complexes derived from the reaction of cyanoacetylhydrazine (<strong>CAH</strong>;<strong>L</strong>) with CuCl<sub>2</sub>•2H<sub>2</sub>O in different solvents were synthesized and characterized. The isolated solid polymeric complexes were investigated using modern conventional physicochemical and spectral (IR, <sup>1</sup>H-NMR, UV-Vis. ESR, Raman), magnetic and thermal studies. The results revealed that <strong>CAH</strong> behaves in different ways towards the coordination of the Cu<sup>2+</sup> ion. The promotion of solvents to the cyano group was discussed on the basis of the solvent and the Cu<sup>2+</sup> ion used. Magnetic and spectral studies suggest octahedral geometry is proposed for the Cu<sup>2+</sup> complexes. EPR studies indicate the existence of polymeric complexes depending on the results of <i>g</i>-values. The results suggest that the number of copper atoms ranges from three to twelve atoms. The molecular modeling is drawn and some chemical characteristics are calculated such as chemical reactivity and energy components are investigated between the different types of the ligands. 展开更多
关键词 Polymeric Cu(ii) complexes ESR Studies Cyanoacetylhydrazine DFT Studies
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Elimination of GGTA1,CMAH,β4GalNT2 and CIITA genes in pigs compromises human versus pig xenogeneic immune reactions
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作者 Jing Xu Jilong Ren +11 位作者 Kai Xu Minghui Fang Meina Ka Fei Xu Xin Wang Jing Wang Zhiqiang Han Guihai Feng Ying Zhang Tang Hai Wei Li Zheng Hu 《Animal Models and Experimental Medicine》 CAS CSCD 2024年第4期584-590,共7页
Background:Pig organ xenotransplantation is a potential solution for the severe organ shortage in clinic,while immunogenic genes need to be eliminated to improve the immune compatibility between humans and pigs.Curren... Background:Pig organ xenotransplantation is a potential solution for the severe organ shortage in clinic,while immunogenic genes need to be eliminated to improve the immune compatibility between humans and pigs.Current knockout strategies are mainly aimed at the genes causing hyperacute immune rejection(HAR)that occurs in the first few hours while adaptive immune reactions orchestrated by CD4 T cell thereafter also cause graft failure,in which process the MHCⅡmolecule plays critical roles.Methods:Thus,we generate a 4-gene(GGTA1,CMAH,β4GalNT2,and CIITA)knockout pig by CRISPR/Cas9 and somatic cell nuclear transfer to compromise HAR and CD4 T cell reactions simultaneously.Results:We successfully obtained 4KO piglets with deficiency in all alleles of genes,and at cellular and tissue levels.Additionally,the safety of our animals after gene editing was verified by using whole-genome sequencing and karyotyping.Piglets have survived for more than one year in the barrier,and also survived for more than 3 months in the conventional environment,suggesting that the piglets without MHCⅡcan be raised in the barrier and then gradually mated in the conventional environment.Conclusions:4KO piglets have lower immunogenicity,are safe in genomic level,and are easier to breed than the model with both MHCⅠandⅡdeletion. 展开更多
关键词 CD4 T cell genetically edited pig immune rejection major histocompatibility complex ii XENOTRANSPLANTATION
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Effects of PI3-k/Akt short hairpin RNA on proliferation, fibronectin production and synthesis of thrombospondin-1 and transforming growth factor-beta(1 ) in glomerular mesangial cells induced by sublytic C5b-9 complexes 被引量:5
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作者 Gao, L. Zhang, Y. Qiu, W. Xu, W. Feng, X. Ren, J. Jiang, X. Wang, H. Zhao, D. Wang, Y. 《南京医科大学学报(自然科学版)》 CAS CSCD 北大核心 2009年第3期344-344,共1页
关键词 连接蛋白 凝血栓蛋白 临床分析 治疗方法 白血病
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Synthesis and Characterization of Nickel(II) and Copper(II) Complexes with Schiff Base (1R,2R)-(-)-Diaminocyclohexane-N,N'-bis(3-tert-butyl-5-(4'-benzoic acid)-salicylidene)
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作者 朱成峰 袁国赞 +1 位作者 盛恩宏 崔勇 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第10期1304-1310,共7页
Two homochiral metallosalen complexes, Ni(salen) (salen = (1R,2R)-(-)-diamino- cyclohexane-N,N′-bis(3-tert-butyl-5-(4′-benzoic acid)-salicylidene) 1 and Cu(salen) 2, have been synthesized and characteri... Two homochiral metallosalen complexes, Ni(salen) (salen = (1R,2R)-(-)-diamino- cyclohexane-N,N′-bis(3-tert-butyl-5-(4′-benzoic acid)-salicylidene) 1 and Cu(salen) 2, have been synthesized and characterized by IR, microanalysis, TGA, powder and single-crystal X-ray crystallography. Both 1 and 2 crystallize in orthorhombic space group P21212 with Z = 4. For 1, a = 12.082(2), b = 15.447(3), c = 18.784(4)A^°, V= 3505.7(12)A^°3, Mr = 731.50, Dc = 1.386 g/cm^3, μ = 0.606 mm^-1, F(000) = 1544, the final GOOF = 1.043, R = 0.0496 and wR = 0.1248 for 4791 observed reflections with I 〉 2σ(I). For 2, a = 12.181(2), b = 15.501(3), c = 18.877(4) A^°, V = 3564.3(12)A^°3, Mr = 736.33, Dc = 1.372 g/cm^3, μ = 0.665 mm^-1, F(000) = 1548, the final GOOF = 1.062, R = 0.0575 and wR = 0.1508 for 4562 observed reflections with I 〉 2σ(I). The crystal structures of 1 and 2 are isostructural with very similar supramolecular structures. An infinite two-dimensional network is generated by hydrogen bonding interactions and intermolecular π…π interactions. 展开更多
关键词 crystal structure SALEN niekel(Ⅱ) complex copper(ii complex
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Synthesis, Characterizations, Biological, and Molecular Docking Studies of Some Amino Acid Schiff Bases with Their Cobalt(II) Complexes
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作者 Mabrouk M. Salama Soad G. Ahmed Safaa S. Hassan 《Advances in Biological Chemistry》 2017年第5期182-194,共13页
The synthesis and structural characterization of cobalt(II) complexes of amino acid Schiff bases was prepared from Salicylaldehyde and three amino acid (Valine, Leucine, and Isoleucine)?in basic medium. The metal comp... The synthesis and structural characterization of cobalt(II) complexes of amino acid Schiff bases was prepared from Salicylaldehyde and three amino acid (Valine, Leucine, and Isoleucine)?in basic medium. The metal complexes was synthesized by treating an ethanolic solution of the ligand with appropriate amount of metal salts [1:2] [M:L] ratio. The synthesized Schiff bases and their metal complexes have been investigated on the bases of elemental chemical analysis, FTIR, electronic spectral,?1HNMR,?13CNMR, MS, molar conductance and magnetic susceptibility measurements. The electronic spectra of the metal complexes and their magnetic susceptibility measurements suggest octahedral structures are the probable coordination geometries for the isolated complexes. The Schiff bases and their metal complexes were preliminary scanned against various strains of microbes to study their biological effect. 展开更多
关键词 SCHIFF Base SALICYLALDEHYDE CO(ii) Metal complex Spectroscopic Techniques BIOLOGICAL Effect MOLECULAR Docking
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Samarium(II) Diiodide Induced Polarity Inversion of π-Allyl Palladium Complexes: The Formation of Allylic Selenides
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作者 XinJianZHAO HuaRongZHAO 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第5期396-397,共2页
Allylic acetates were reduced with Pd(0)-SmI2 in the presence of ArSeBr to form corresponding allylic selenides in good yields.
关键词 Allyl acetates allylic selenides arylselenenyl bromides palladium complexes polarity inversion. Samarium(ii) Diiodide Induced Polarity Inversion of p-Allyl Palladium complexes: The Formation of Allylic Selenides Xin Jian ZHAO1 Hua Rong ZH
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Spectroscopic and molecular structure characterization of the bis(2-aminophenol)(5, 10, 15, 20-tetraphenylporphyrinato) cobalt(II) complex
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作者 Yassin Belghith Anissa Mansour +1 位作者 Jean-Claude Daran Habib Nasri 《Open Journal of Inorganic Chemistry》 2012年第4期81-87,共7页
The reaction of the cobalt(II) meso-tetraphenylporphyrin (TPP) starting material with an excess of 2-aminophenol (Hon) in organic solvents, yields the cobalt(II) porphyrin species [CoII(TPP)(Hon)2] (1). This compound ... The reaction of the cobalt(II) meso-tetraphenylporphyrin (TPP) starting material with an excess of 2-aminophenol (Hon) in organic solvents, yields the cobalt(II) porphyrin species [CoII(TPP)(Hon)2] (1). This compound has been characterized by UV-vis., IR, MSI MS and 1H NMR spectroscopy. The UV-vis data and especially the proton NMR results, for the isolated product, indicated that complex 1 is a Co(II) mesoporphyrin derivative.The X-ray molecular structure of the title compound bis(2-aminophenol) (tetraphenylporphyrinato) cobalt(II) has been determined. This structure is the first one reported of a metalloporphyrin with a 2-aminophenol axial ligand species. The central metal is hexacoordinated by the four nitrogen atoms of the pyrrole rings and the nitrogen atoms of the two Hon trans axial ligands. 展开更多
关键词 MESO-TETRAPHENYLPORPHYRIN Cobalt(ii) 2-AMINOPHENOL Cobalt(ii) complex X-Ray Molecular Structure
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