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Trimer formation of 6-methyl-1,3,5-triazine-2,4-diamine in salt with organic and inorganic acids:analysis of supramolecular architecture

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Science China Chemistry 2014年第12期57卷 1731-1737,1-2页

作者： XIAO Zhen yu WANG Wen Qiang XUE Rui yu ZHAO Lei WANG Lei ZHANG YiHeng College of Chemistry and Molecular Engineering Qingdao University of Science and Technology

Although the numbers of co-crystals,salts,polymorphs,hydrates,and solvates are growing steadily,trimers that contain both inorganic and organic acids are still very rare in the Cambridge Structural Database(CSD).When 3,5-dihydroxybenzoic acid was crystallized readily with 6-methyl-1,3,5-triazine-2,4-diamine in a 4:3 ratio of ethanol and water by adding a few drops of nitric acid upon slow evaporation in ambient conditions,6-methyl-1,3,5-triazine-2,4-diamine and 3,5-dihydroxybenzoic acid with the nitric acid form of 1:1:1 an inorganic-organic salt formulated as[(C4H8N5+)·(NO3-)·(C7H6O4)].The supramolecular architecture,which is quite elegant and simple,appeared as stacking of a 3D network in *** transfer from the HNO3to 6-methyl-1,3,5-triazine-2,4-diamine N acceptor(triazine N)occurred in the organic salt and led to the ionic heterosynthon in the *** among the–COOH,–OH,NO3–,and–NH–functional groups for the observed hydrogen bond synthon was examined in the *** adduct,recognition among the constituents is established through N–H···O,O–H···N,and O–H···O hydrogen *** agomelatine molecules are linked through the intermolecular hydrogen bonding interactions(O–H···O)to form a 1D *** addition,the nitric acid anions and base cations act as donors and acceptors of hydrogen bonds and interlink,almost to co-planarity,the hydrogen-bonded chains through interchain N–H···O,O–H···N,as well as O–H···O interactions into a 2D sheet *** N–H···O interactions were found to play an important role in the formation of the final 3D *** salt was characterized by elemental analysis,IR,thermogravimetric analysis,and singlecrystal X-ray diffraction,to better understand how intermolecular interactions influence its supramolecular assembly.

关键词： supramolecular hydrogen bonds crystal structure salt

Static mechanical properties of hybrid RTM-made composite Ⅰ-and Ⅱ-beams under three-point flexure

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Chinese Journal of Aeronautics 2015年第3期28卷 903-913页

作者： Fu yu Xiong Junjiang Luo Chuyang yun Xinyao School of Transportation Science and Engineering Beihang University

Abstract This paper deals with three-point flexure tests on hybrid I- and II-beams, made out of multi-layer carbon fiber/epoxy resin （including twill woven fabric CF3031/5284 and unidirectional cord fabric U3160/5284） reinforced composites, processed using the RTM （resin transfer molding） technique. Static bending properties were determined and failure initiation mechanism was deduced from experimental observations. Failure mode of the tested hybrid RTM-made I-beams can be reckoned to be characteristic of the delamination from the cutout edge within the web and the debonding propagation along the interface between the inverted triangular resin-rich zone and the adjacent curved web until local buckling within the curved webs around the conjunction fillet region. In contrast, as distinct from hybrid RTM I-beams subjected to three-point bending loading, hybrid RTM-made H-beams in three-point flexure tests experienced the resin debonding in the inverted triangular resin-rich zones and the debonding propagation along the interface between the inverted triangular resin-rich zone and the adjacent curved web until complete separation of the curved web from the flange. Progressive damage models （PDMs） were presented to predict fail- ure loads and process of hybrid RTM-made I- and N-beams under three-point flexure. Good cor- relation was achieved between experimental and numerical results.

关键词： Beam Composites Experiment Fabric Molding Simulation

Syntheses and Crystal Structures of Two New α-Aminophosphonate Derivatives Containing Thieno[2,3-d]pyrimidine

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Chinese Journal of Structural Chemistry 2015年第6期34卷 879-884页

作者： ZHU Xi-Feng GUO Yan-Chun yu Zhi-Ran LIAO Xin-Cheng ZHAO yu-Fen The College of Chemistry and Molecular Engineering The Key Laboratory of Chemical Biology and Organic Chemistry of Henan Province Zhengzhou University Department of Chemistry College of Chemistry and Chemical Engineering The Key Laboratory for Chemical Biology of Fujian Province Xiamen University

Two new a-aminophosphonate derivatives containing thieno[2,3-d]pyrimidine, diethyl（（（6-ethyl-2-methyl-4-oxothieno[2,3-d]pyrimidin-3 （4H）-yl）amino）（4-methoxyphenyl）methyl） phosphonate （1） and diethyl（（4-bromophenyl）（（6-ethyl-2-methyl-4-oxothieno[2,3-d]pyrimidin-3 （4//）-yl）amino）methyl）phosphonate （2）, have been synthesized by a facial phosphorylated reaction, and their structures were characterized by NMR, IR, HRMS and X-ray single-crystal diffraction. Compound 1 （C21H28N3O5PS, Mr = 465.49） belongs to the orthorhombic system, space group P212121, with a = 10.83653（16）, b = 12.04906（19）, c = 18.0061（3） A, V= 2351.06（6） A3, Z= 4, Dc= 1.315 g/cm3, p = 2.177 mm-1, F（000） = 984.0, the final R = 0.0389 and wR = 0.0985 for all data. Compound 2 （C20H25BrN304PS, Mr = 514.37） belongs to the orthorhombic system, space group P212121, with a = 10.9187（5）, b = 11.9522（4）, c = 17.7667（7） A, V= 2318.60（16） A3, Z = 4, Dc= 1.474 g/cm3,μ = 4.175 mm^-1, F（000） = 1056.0, the final R = 0.0367 and wR = 0.0946 for all data.

关键词： thieno[2,3-d]pyrimidine a-aminophosphonate derivatives synthesis crystal structure

Adsorption of mercury on laterite from Guizhou Province,China

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Journal of Environmental Sciences 2008年第11期20卷 1328-1334页

作者： yu Xiaohong ZHU Lijun GUO Baiwei HE Shouyang The State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China Key Laboratory of Karst Environment and Geohazard Prevention Ministry of Education Guiyang 550003 China College of Civil Engineering and Building Construction of Guizhou University Guiyang 550003 China

The adsorption behaviors of Hg(Ⅱ) on laterite from Guizhou Province,China,were studied and the adsorption mechanism was *** results showed that different mineral compositons in the laterite will cause differences in the adsorption capacity of laterite to Hg(Ⅱ).Illite and non-crystalloids are the main contributors to enhancing the adsorption capacity of laterite to Hg(Ⅱ).The pH of the solution is an important factor affecting the adsorption of Hg(Ⅱ) on *** alkalescent environment (pH 7-9) ...

关键词： adsorption laterite Hg(Ⅱ) pH isotherm kinetics

MODIFIED MORLEY ELEMENT METHOD FOR A FOURTH ORDER ELLIPTIC SINGULAR PERTURBATION PROBLEM

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Journal of Computational Mathematics 2006年第2期24卷 113-120页

作者： Ming Wang Jin-chao Xu yu-cheng Hu LMAM School of Mathematical Science Peking University Beijing 100871 China School of Mathematical Science Peking University Beijing 100871 China and Department of Mathematics Pennsylvania State University USA School of Mathematical Science Peking University Beijing 100871 China

This paper proposes a modified Morley element method for a fourth order elliptic singular perturbation problem. The method also uses Morley element or rectangle Morley element, but linear or bilinear approximation of finite element functions is used in the lower part of the bilinear form. It is shown that the modified method converges uniformly in the perturbation parameter.

关键词： Morley element Singular perturbation problem.

Experimental study on detonation parameters and cellular structures of fuel cloud

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Acta Mechanica Sinica 2012年第2期28卷 438-443页

作者： Li-Feng Xie Bin Li yu-Lei Zhang School of Chemical Engineering Nanjing University of Science and Technology210094 NanjingChina

In this paper, detonation parameters of fuel cloud, such as propylene oxide （PO）, isopropyl nitrate （IPN）, hex- ane, 90# oil and decane were measured in a self-designed and constructed vertical shock tube. Results show that the deto- nation pressure and velocity of PO increase to a peak value and then decrease smoothly with increasing equivalence ra- tio. Several nitrate sensitizers were added into PO to make fuel mixtures, and test results indicated that the additives can efficiently enhance detonation velocity and pressure of fuel cloud and one type of additive n-propyl nitrate （NPN） played the best in the improvement. The critical initiation energy that directly initiated detonation of all the test liquid fuel clouds showed a U-shape curve relationship with equiva- lence ratios. The optimum concentration lies on the rich-fuel side （;b 〉 1）. The critical initiation energy is closely related to molecular structure and volatility of fuels. IPN and PO have similar critical values while that of alkanes are larger. Detonation cell sizes of PO were respectively investigated at 25;C, 35;C and 50;C with smoked foil technique. The cell width shows a U-shape curve relationship with equivalence ratios at all temperatures. The minimal cell width also lies on the rich-fuel side （;b 〉 1）. The cell width of PO vapor is slightly larger than that of PO cloud. Therefore, the deto- nation reaction of PO at normal temperature is controlled by gas phase reaction.

关键词： Cloud detonation Detonation velocity Deto- nation pressure - Critical initiation energy Cell size

Security Communication Model of Wireless Trade System

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Wuhan University Journal of Natural Sciences 2005年第1期10卷 152-156页

作者： ZHANGWen-kai ZHANGSi-yu DepartmentofComputerScienceandEngineering BeijingInstituteofTechnologyBeijing100081China BeijingNettingNetworkTechnologiesCoLtd Beijing100088China

This paper proposes a C/S system model for K-Java and PDA named *** is a discussion and proposal on information security and solutions for R-Java handsets and PDAsin wireless network. It also explains the scheme which between client security module and serversecurity module. Also, We have developed a Security Server and a K-Java encryption module fore-commerce system and other trade systems.

关键词： wirekss trade data encryption security module K-Java

Physical studies of minor actinide transmutation in the accelerator-driven subcritical system

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Nuclear Science and Techniques 2019年第6期30卷 35-43页

作者： Hai-Yan Meng Yong-Wei Yang Ze-Long Zhao Qing-yu Gao yu-Cui Gao Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China School of Nuclear Science and Technology University of Chinese Academy of Sciences Beijing 100049 China

The accelerator-driven subcritical system (ADS) with a hard neutron energy spectrum was used to study transmutation of minor actinides (MAs). The aim of the study was to improve the efficiency of MA transmutation while ensuring that variations in the effective multiplication factor (keff) remained within safe margins during reactor operation. All calculations were completed using code COUPLE3.0. The subcritical reactor was operated at a thermal power level of 800 MW, and a mixture of mononitrides of MAs and plutonium (Pu) was used as fuel. Zirconium nitride (ZrN) was used as an inert matrix in the fuel elements. The initial mass composition in terms of weight percentages in the heavy metal component (IHM) was 30.6% Pu/IHM and 69.4% MA/IHM. To verify the feasibility of this MA loading scheme, variations in keff, the amplification factor of the core, maximum power density and the content of MAs and Pu were calculated over six refueling cycles. Each cycle was of 600 days duration, and therefore, there were 3600 effective full power days. Results demonstrated that the effective transmutation support ratio of MAs was approximately 28, and the ADS was able to efficiently transmute MAs. The changes in other physical parameters were also within their normal *** is concluded that the proposed MA transmutation scheme for an ADS core is reasonable.

关键词： ADS COUPLE3.0 MA Transmutation Subcritical reactor

Characterizing and optimizing Java-based HPC applications on Intel many-core architecture

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Science China(Information Sciences) 2017年第12期60卷 207-223页

作者： Yang yu Tianyang LEI Haibo CHEN Binyu ZANG School of Computer Science Fudan University Institute of Parallel and Distributed Systems Shanghai Jiao Tong University

The increasing demand for performance has stimulated the wide adoption of many-core accelerators like IntelR Xeon PhiTMCoprocessor, which is based on Intel’s Many Integrated Core architecture. While many HPC applications running in native mode have been tuned to run efficiently on Xeon Phi, it is still unclear how a managed runtime like JVM performs on such an architecture. In this paper, we present the first measurement study of a set of Java HPC applications on Xeon Phi under JVM. One key obstacle to the study is that there is currently little support of Java for Xeon Phi. This paper presents the result based on the first porting of Open JDK platform to Xeon Phi, in which the Hot Spot virtual machine acts as the kernel execution engine. The main difficulty includes the incompatibility between Xeon Phi ISA and the assembly library of Hotspot *** evaluating the multithreaded Java Grande benchmark suite and our ported Java Phoenix benchmarks, we quantitatively study the performance and scalability issues of JVM on Xeon Phi and draw several conclusions from the study. To fully utilize the vector computing capability and hide the significant memory access latency on the coprocessor, we present a semi-automatic vectorization scheme and software prefetching model in Hot *** with 60 physical cores and tuning, our optimized JVM achieves averagely 2.7 x and 3.5 x speedup compared to Xeon CPU processor by using vectorization and prefetching accordingly. Our study also indicates that it is viable and potentially performance-beneficial to run applications written for such a managed runtime like JVM on Xeon Phi.

关键词： many-core Java Xeon Phi HPC prefetching