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Chinese Chemical Letters 2016年第3期27卷 417-422页

作者： bo Li Xu-Zhuo Sun College of Chemistry and Chemical Engineering Henan University of Technology

Two new supramolecular architectures {（hC2O4）2^2- [C6h（18）N2^2＋ C（36）h（36）N（24）O（12）]} 12h2O（1） and{（C6h5SO3）22 [C6h（18）N22＋ C（36）h（36）N（24）O（12）]} 12h2O（2） were synthesized and characterized by singlecrystal X-ray diffraction, thermogravimetric analysis and X-ray powder diffraction. Compound 1contains infinite two dimensional（2D） L18（8）14（8）8（4） type anion–water aggregates [（hC2O4）4（h2O）（22）]^4- and results in the construction of sandwich-like three dimensional（3D） networks. In compound 2, honeycomb-like three dimensional（3D） networks are fabricated by one dimensional（1D）＂W＂-like T5（0）A2 type anion–water clusters [（C6h5SO3）（h2O）6]^-. These results indicate that anionic groups play a crucial role in modulating the structures of water clusters with their spatial structure and binding sites. In these two structures, the majority of interactions are O...h and h...h interactions on the hirshfeld surface, which means that hydrogen bonding and hydrophobic interactions are the dominate drive forces in forming these supramolecular systems.

关键词： Cucurbituril Supramolecular Water clusters Anion templates Pseudorotaxane

Congruence Subgroups of hecke Groups

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Acta Mathematica Sinica,English Series 2009年第6期25卷 931-944页

作者： bo ChEN Ping Zhi YUAN School of Science Chongqing Jiaotong University Chongqing 400074 P. R. China School of Mathematics South China Normal University Guangzhou 510631 P. R. China

hecke groups are an important tool in subgroups of hecke groups play an important rule investigating functional equations, and congruence in research of the solutions of the Dirichlet series. When q, m are two primes, congruence subgroups and the principal congruence subgroups of level m of the hecke group h（√q） have been investigated in many papers. In this paper, we generalize these results to the case where q is a positive integer with q ≥ 5, √q ￠ Z and m is a power of an odd prime.

关键词： hecke group principal congruence subgroup congruence subgroup

hafnium carbide structural foams synthesized from polymer precursors

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中国有色金属学会会刊：英文版 2006年第A2期16卷 85-88页

作者： FAN hai-bo YANG hong N. K. RAVALA h. C. WIKLE III R. h. ZEE B. A. ChIN 275 Wilmore Labs Auburn University Auburn AL 36849-5341 USA

hafnium carbide (hfC) was applied in space and aerospace due to its ultra high melting temperature, high specific strength and moderate oxidation resistance. A novel synthesizing method was used to produce low density and high strength hfC structural foams through the thermolysis and pyrolysis of hf containing polymer precursors (mixing of hafnium trifluoroacetylacetonate and epoxy) under vacuum atmosphere. The X-ray diffraction analysis shows that the produced foam is primarily composed of hfC containing 9%-10% hfO2. Several polymer powder compaction methods were used to improve the mechanical properties of hfC foam. Compression strengths of 200 MPa are achieved for hfC foams with density of 1.9 g/cm3 (total porosity about 85%). The proposed methodology of synthesizing hfC foam has the advantages of simple, inexpensive and less production time than alternate methods.

关键词：聚合物前提碳化铪结构性泡沫保护性涂层合成力学性质超高温

Gender difference in the effect of daytime sleep on declarative memory for pictures

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第7期10卷 536-546页

作者： bo WANG Xiao-lan FU State Key Laboratory of Brain and Cognitive Seience Institute of Psychology Chinese Academy of Sciences Beijing 100101 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

Objective:To investigate gender difference in the effects of daytime sleep on item and source memories,which are dissociable elements of declarative memory,and the effects of sleep on recollection and familiarity,which are two processes underlying recognition. Methods:Participants saw a series of pictures with either blue or red background,and were then given a pretest for item and source memories. Then males and females respectively were randomly assigned either to a wake or a sleep condition. In the wake condition,participants remained awake until the posttest;in the sleep condition,participants slept for 1 h until awakened and asked to remain awake until the posttest. Results:Daytime sleep contributed to retention of source memory rather than item memory in females,whereas males undergoing daytime sleep had a trend towards increased familiarity. For females,however,neither recollection nor familiarity appeared to be influenced by daytime sleep. Conclusion:The mechanism underlying gender difference may be linked with different memory traces resulting from different encoding strategies,as well as with different electrophysiological changes during daytime sleep.

关键词： Gender difference Declarative memory Recollection Familiarity Daytime sleep

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Wrtsil公司跻身机车市场

国外内燃机车 2011年第4期 38-39页

作者： bo svensson 孙宇

芬兰瓦锡兰公司(Wrtsil)与俄罗斯运输机械制造控股公司(TMh)成立一家合资公司,共同开发和制造用于铁路机车、船舶和发电等用途的柴油机。

关键词： Wartsila公司 TMh公司 Wartsila 20型柴油机机车市场

On Proof of the C^1 Stability Conjecture

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Acta Mathematica Sinica,English Series 2005年第3期21卷 533-540页

作者： Yong ZhANG Shao bo GAN School of Mathematical Sciences Soochow University Suzhou 215006 P. R. China School of Mathematical Sciences Peking University Beijing 100084 P. R. China

It seems that in Mane＇s proof of the C^1 Ω-stability conjecture containing in the famous paper which published in I. h. E. S. （1988）, there exists a deficiency in the main lemma which says that for f ∈F^1 （M） there exists a dominated splitting TMPi（f） =Ei^s the direlf sum of E and F Fi^u（O 〈 i 〈 dim M） such that if Ei^s is contracting, then Fi^u is expanding. In the first part of the paper, we give a proof to fill up this deficiency. In the last part of the paper, we, under a weak assumption, prove a result that seems to be useful in the study of dynamics in some other stability context.

关键词： The C^1 stability conjecture Dominated splitting Shadowing property Axiom A No-cycle condition

A long-form α-neurotoxin from cobra venom produces potent opioid-independent analgesia

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Acta Pharmacologica Sinica 2006年第4期27卷 402-408页

作者： bo-wenChEN RonghAN PaulFREID LaurenceNRAYMOND Department of Pharmacology Soochow University School of MedicineSuzhou 215007China ReceptoPharm PlantationFlorida 33324USA

Aim:In light of the antinociceptive activity of the short-chain neurotoxin,cobrotoxin,and other acetylcholine antagonists,the antinociceptive activity andmechanisms of cobratoxin(CTX),a long-chain postsynaptic α-neurotoxin,wasinvestigated in rodent pain ***:CTX was administered intraperito-neally(30,45,68 μg/kg),intra-cerebral ventricularly(4.5 μg/kg)or microinjectedinto periaqueductal gray(PAG;4.5 μg/kg).The antinociceptive action was testedusing the hot-plate and acetic acid writhing tests m mice and *** involve-ment of the cholinergic system and opioid system in CTX-induced analgesia wasexamined by pretreatment of animals with atropine(0.5 mg/kg,im;or 10 mg/kg,ip)or naloxone(1 and 5 mg/kg,ip).The effect of CTX on motor activity was testedusing the Animex ***:CTX exhibited a dose-dependent analgesic ac-tion in mice as determined by both the hot-plate and acetic acid writhing *** peak effect of analgesia was seen 3 h after *** the mouse aceticacid writhing test,the intra-cerebral ventricular administration of CTX at 4.5 μg/kg(1/12th of a systemic dose)produced marked analgesic *** ofCTX(4.5 μgkg)into the PAG region did not elicit an analgesic action in rats in thehot-plate *** at 0.5 mg/kg(im)and naloxone at 1 and 5 mg/kg(ip)bothfailed to block the analgesic effects of CTX,but atropine at 10 mg/kg(ip)didantagonize the analgesia mediated by CTX in the mouse acetic acid writhing *** acid(300 mg/kg)did not enhance the analgesic effects of *** highest effective dose of 68 μg/kg the neurotoxin did not change the sponta-neous mobility of ***:CTX has analgesic effects,which are medi-ated in the central nervous system though not through the *** centralcholinergic system but not opioid system appears to be involved in theantinociceptive action of CTX.

关键词： cobratoxin analgesia periaqueductal gray matter atropine naloxone

Rhodium(Ⅰ)-Catalyzed Enantioselective C(sp^(3))-h Functionalization via Carbene-Induced Asymmetric Intermolecular C-h Insertion

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Chinese Journal of Chemistry 2021年第7期39卷 1911-1915页

作者： bo Liu Ming-hua Xu Shenzhen Grubbs Institute and Department of Chemistry Guangdong Provincial Key Laboratory of CatalysisSouthern University of Science and Technology1088 Xueyuan BoulevardShenzhenGuangdong518055 China Shanghai Institute of Materia Medica Chinese Academy of Sciences555 Zuchongzhi RoadShanghai201203 China

Main observation and conclusion Transition-metal-catalyzed C-h insertion of metal-carbene represents an excellent and powerful approach for C-h ***,despite remarkable advances in metal-carbene chemistry,transition metal catalysts that are capable of enantioselective intermolecular carbene C-h insertion are mainly constrained to dirhodium(Ⅱ)and iridium(Ⅲ)-based complexes.

关键词： Asymmetric catalysis C-h functionalization carbene C-h insertion Rhodium

Synthesis of β-alkynyl α-amino acids via palladium-catalyzed alkynylation of unactivated C(sp^3)-h bonds

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Science China Chemistry 2015年第8期58卷 1345-1348页

作者： bo Wang Gang he Gong Chen Department of Chemistry the Pennsylvania State University University Park

β-Di-substituted α-amino acids(AAs) contain adjacent carbon stereogenic centers and pose considerable synthetic challenge. Complementary to the conventional synthesis strategies based on the transformation of existing functional groups, we envisioned these molecules could be quickly accessed via selective functionalization of sp3 hybridized C-h bonds on the side chains of common α-AA precursors. We report a readily applicable method to prepare β-alkynyl α-amino acids via Pd-catalyzed diastereoselective C(sp3)-h alkynylation of common α-amino acids precursors with acetylene bromide.

关键词： α-amino acids C-h functionalization palladium

Insight on corrosion behavior of a Cu-P-Cr-Ni steel with different Ni contents by electrochemical and periodic immersion corrosion experiments

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Journal of Iron and Steel Research International 2023年第3期30卷 580-590页

作者： Zhi-wei Lian Tian-en Peng Shuang hu bo he Xue-wen hu Tao Zhu bo Jiang School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Technical Center Ma’anshan Iron&Steel Co.Ltd.Ma’anshan 243041AnhuiChina

Corrosion behavior of Cu-P-Cr-Ni weathering steels with different nickel contents was studied by periodic immersion corrosion test for 72 *** mass loss method was used to evaluate the weatherability of weathering *** rust layers formed on weathering steel were characterized by scanning electron microscopy,X-ray diffraction,electron probe microanalysis,X-ray photoelectron spectroscopy,and electrochemical *** results of periodic immersion corrosion test for 72 h showed that the mass loss rates of Cu-P-Cr-0.14Ni steel and Cu-P-Cr-0.04Ni steel were 1.57 and 1.61 g/(m^(2)h),*** to the electrochemical experiment,the corrosion potentials of the two tested steels at the initial stage of corrosion were-0.6852 and-0.7037 V,*** the corrosion time reaching 72 h,the corrosion potential difference between the two tested steels was gradually *** the initial stage,NiO was formed in the rust layer and can dramatically promote the crystallization of corrosion products to improve the stability of the rust *** periodic immersion corrosion test for 72 h,Ni element had no obvious *** this time,it was mainly the enrichment of Cu and Cr elements in the form of CuO and Cr_(2)O_(3)in the rust layer that could further protect the matrix.

关键词： Weathering steel Ni Electrochemical experiment Periodic immersion corrosion Corrosion behavior