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Design and Synthesis of Novel 5-Sulfoxide-substituted Pyrazolo[5,1-d][1,2,3,5]tetrazin-4(3H)ones

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Chinese Chemical Letters 2005年第9期16卷 1143-1146页

作者： Yah Chao WU Xiao Mao ZOU Fang Zhong HU hua zheng yang State Key Laboratory of Element-organic Chemistry Institute of Element-organic Chemistry Nankai University Tianjin 300071

A series of novel 5-sulfoxide-substituted pyrazolo[5,1-d] [1,2,3,5]tetrazin-4（3H）ones 4a-j were designed and efficiently synthesized via a diazotization of 5-amine-3-methylsulfinyl- 1H-pyrazole, followed by cycloaddition with aryl isocyanate. A possible reaction mechanism is outlined and discussed. These new compounds exhibit some biological activity as preliminary bioassay indicated. Their structures were confirmed with ^1H NMR, IR and elemental analysis.

关键词： Sulfoxide-substituted nitrogen heterocycle diazotization cycloaddition

A Survey of Identity-based and Attribute-based Cryptography

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南京邮电大学学报（自然科学版） 2010年第1期30卷 11-17页

作者： QI zheng-hua yang Geng REN Xun-yi College of Computer Nanjing University of Posts and Telecommunications Nanjing 210003 China

We survey the state of research on identity-based cryptography and attribute-based *** firstly review the basic concepts of identity-based cryptographic schemes in which users' identifier information such as email or IP addresses instead of digital certificates can be used as public key for encryption or signature verification,and subsequently review some important identity-based encryption,signature and signcryption *** we give our research on Identity-Based Encryption-Signature(IBES) *** also survey the attribute-based cryptographic schemes in which the identity of user is viewed as a set of descriptive attributes,including some important attribute-based encryption and signature *** subsequently give our research on Attribute-Based Encryption and Identity-Based Signature (ABE-IBS) *** methods aim at efficiently improving the security of wireless sensor ***,we propose a few interesting open problems concerning with practical and theoretical aspects of identity-based cryptography and attribute-based cryptography.

关键词：计算机网络网络安全密码系统服务器

Synthesis and Structure of 3-Aryl-5-cyano-6-methylthio pyrimidine2,4-diones

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Chinese Chemical Letters 1999年第3期10卷 191-192页

作者： hua Yin LIU Guang Fu yang hua zheng yang(State Key Laboratory of Elemento-Organic Chemistry, Institute of Elemento-Organic Chemistry,Nankai University, Tianjin 300071) State Key Lab. Elemento-Organ. Chem. Inst. of Elemento-Organic Chemistry Nankai University Tianjin 300071 China

The title compounds of 3-aryl-5-cyano-6-methylthiopyrimidine2.4-diones weresynthesized by the reaction of ethy1 2-cyano-3.3'dimethylthioacrylate with arylureas. The compound(Ar＝p-CH_3OC_6H_4) was recrystallized in acetone/petroleum in space group P2_(1/n) with a＝1. 1602 (2).b=1.5921(3), c＝1.3918 (3)um. β=94.38 (3)°for Z=8. R=*** X-ray analysis showedthat there is H-bond interaction among molecules.

关键词： Synthesis crystalline structure

Effect of Ce on microstructure and mechanical properties of Mg-Zn-Ce magnesium alloys

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China Foundry 2023年第4期20卷 271-279页

作者： Hong-fei Wu Wen-xin Hu Shao-bo Ma zheng-hua yang Wei Wang Feng Liu Wei He State Key Laboratory of Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization Baotou 014030Inner MongoliaChina Baotou Research Institute of Rare Earths Baotou 014030Inner MongoliaChina

The Mg-6Zn alloy with different contents of Ce was prepared by the gravity casting method,and then the Mg-6Zn-xCe(x=0,0.5,1.0,1.5,wt.%)alloys were extruded at 300℃and 350℃ after solution *** phase constitution and microstructure evolution of Mg-Zn-xCe alloys were analyzed by X-ray diffraction(XRD),scanning electron microscopy(SEM),energy dispersive spectroscopy(EDS)and electron backscattering diffraction(EBSD).Meanwhile,the mechanical properties of the alloy were tested at room *** as-cast alloys,the results show that the main compound in Mg-6Zn alloy is Mg4Zn7 phase,and the main compound is T-(MgZn)12Ce phase after the addition of different amounts of *** microstructure and distribution of second phases are greatly improved after extrusion at 300℃and 350℃.Compared with initial mechanical properties,the strength and elongation increase obviously by means of extrusion at different *** addition,the microstructure after extrusion at 350℃is further analyzed according to EBSD *** results show that rare earth element Ce probably promotes the activation of non-basal slip during the deformation process with the increase of Ce,which reduces the strength of basal texture and thus improves the plasticity of the ***,the increase of grain boundary migration ability leads to the gradual increase of recrystallization grain size and decreases the strength.

关键词： Mg-Zn-Ce extrusion microstructure mechanical properties magnesium alloys

The　Synthesis　and　Biological　Activity　of　N－Arylamino　Carbonyl　Methylene　1，2－Benzothiazine　1，1－Dioxides

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Chinese Chemical Letters 1996年第12期7卷 1087-1088页

作者： Guo Feng ZHAO hua zheng yang(Institute of Elemento-Organic Chemistry Nankai University, Tianjin 300071) NANKAI UNIV INST ELEMENTOORGAN CHEMTIANJIN 300071PEOPLES R CHINA

s: In this paper four new 1.2-benzothiazine 1. 1 -dioxide derivatives 4 were synthesized by the reaction of 4 -ethylenedioxy -2H - 1. 2 -benzothiazine 1. 1-dioxide 2 with 2-chloracetamides 3 under the action of base. ... 详细信息

关键词： Activity Biological and Arylamino Benzothiazine

Design and Synthesis of Novel Fluorine-containing Acrylates

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Chinese Chemical Letters 2005年第10期16卷 1293-1296页

作者： Yan Chao WU Chao WU Xiao Mao ZOU Fang Zhong HU hua zheng yang State Key Laboratory of Element-Organic Chemistry Institute of Element-Organic Chemistry Nankai University Tianjin 300071

A series of novel fluorine-containing acrylates 6a-6g were synthesized via the condensation of ethyl cyanoacetate and trifluoroacetic anhydride, followed by chloridization and the coupling reaction with amines. These new compounds exhibited some biological activity as preliminary bioassay indicated. A plausible reaction mechanism was outlined and discussed.

关键词： Fluorine-containing compound acrylates synthesis.

Impact of Local Climate Zones on the Urban Heat and Dry Islands in Beijing:Spatial Heterogeneity and Relative Contributions

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Journal of Meteorological Research 2024年第1期38卷 126-137页

作者： Zuofang zheng Fu LUO Nana LI hua GAO Yuanjian yang Institute of Urban Meteorology China Meteorological AdministrationBeijing 100089 School of Atmospheric Physics Nanjing University of Information Science&TechnologyNanjing 210044 Key Laboratory of Urban Meteorology China Meteorological AdministrationBeijing 100089

Based on the building height and density data on a 100-m resolution,hourly 2-m temperature and humidity data at83 automatic weather stations,and gridded local climate zone(LCZ)data on a 120-m resolution in urban Beijing in2020,this study first employs the semivariogram combined with building parameters to calculate spatial correlations and has identified an LCZ grid resolution of 500 m suitable for best usage of the available observation ***,how the spatially heterogeneous LCZs affect and contribute to the canopy urban heat island intensity(UHII)and urban dry island intensity(UDII)are quantitatively *** is found that UHII is high in winter and low in summer with a unimodal diurnal variation while UDI is low in winter but high in summer with a bimodal diurnal *** LCZ with compact mid-rise(open high-rise)buildings exhibits the highest UHII(UDII),followed by the compact high-rise(compact low-rise),while the LCZ of scattered trees presents both the lowest UHII and the lowest *** most significant difference in the UHII(UDII)among the nine LCZ types in the urban area of Beijing is2.62℃(1.1 g kg^(-1)).Area-weighted averaging analysis reveals that the open mid-rise LCZ is the most significant contributor to the UHII(UDII),immediately followed by compact mid-rise(open low-rise),with the least contribution from bare rock or paved(scattered trees).The results also indicate that beyond the intrinsic physical properties of the LCZs of a city,their area proportions cannot be overlooked in evaluating their impact on the UHI and *** quantitatively findings could help urban planners to create a livable urban climate and environment by adjusting the relevant land use.

关键词： local climate zone(LCZ) urban heat island(UHI) urban dry island(UDI) distribution pattern contribution rate Beijing

A New Approach to Ethyl 1-Aroyl/Aroylmethyl-5-methyl-3- methylthiopyrazole-4-carboxylates: High Regioselectivity in Alkylation and Acylation Reactions between N-1 and N-2 of a Pyrazole Derivative

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Chinese Chemical Letters 2005年第9期16卷 1161-1164页

作者： Li Rong WEN Gui Long ZHAO Ming LI Wen Ying QI Xiu Li ZHANG hua zheng yang College of Chemistry and Molecular Engineering Qingdao University of Science and Technology Qingdao 266042 State Key Laboratory of Elemento-organic Chemistry Institute of Elemento-Organic Chemistry Nankai University Tianjin 300071 Ocean Food and Drug Institute Ocean University of China Qingdao 266003

Two series, totalizing twelve, of new compounds, ethyl 1-aroyl/aroylmethyl-5-methyl-3- methylthiopyrazole-4-carboxylates 5/6, have been synthesized via highly regioselective acylation and alkylation of ethyl 3-methyl-5-methylthio-1H- pyrazole-4-carboxylate 2a with aroyl chloride 3 and alpha-tosyloxysubstitutedacetophenones 4. Unexpected structures of the product have been unambiguously determined by both X-ray crystallographic analysis and 2D NMR.

关键词： Pyrazole regioselectivity X-ray crystallographic analysis 2D NMR

Experimental observation of spontaneous symmetry breaking in a quantum phase transition

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 34-39页

作者： Wen Ning Ri-hua zheng Jia-Hao Lu Fan Wu Zhen-Biao yang Shi-Biao zheng Fujian Key Laboratory of Quantum Information and Quantum Optics College of Physics and Information EngineeringFuzhou UniversityFuzhou 350108China Hefei National Laboratory Hefei 230088China

Spontaneous symmetry breaking(SSB)plays a central role in understanding a large variety of phenomena associated with phase transitions,such as superfluid and *** far,the transition from a symmetric vacuum to a macroscopically ordered phase has been substantially *** process bridging these two distinct phases is critical to understanding how a classical world emerges from a quantum phase transition,but so far remains unexplored in *** here report an experimental demonstration of such a process with a quantum Rabi model engineered with a superconducting *** move the system from the normal phase to the superradiant phase featuring two symmetry-breaking field components,one of which is observed to emerge as the classical *** results demonstrate that the environment-induced decoherence plays a critical role in the SSB.

关键词： quantum phase transition Rabi model spontaneous symmetry breaking superconducting circuit Schrodinger cat states