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Thermal Behavior, Specific Heat Capacity and Adiabatic Time-to-explosion of gDN

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Chemical Research in Chinese Universities 2009年第1期25卷 76-80页

作者： YANg Xing-kun XU Kang-zhen ZHAO Feng-qi YANg Xin WANg Han SONg Ji-rong WANg Yao-yu College of chemistry and Chemical Engineering Xinyang Normal University Xinyang 464000 P. R. China Xi＇an Modern chemistry Research Institute Xi＇an 710065 P. R. China Shaanxi Key Laboratory of physico-inorganie chemistry Northwest University Xi＇an 710069 P. R. China

A new compound, [（NH2）2C=NH2]＋N（NO2）2-（gDN）, was prepared by mixing ammonium dinitramide （ADN） and guanidine hydrochloride in water. The thermal behavior of gDN was studied under the non-isothermal conditions with DSC and Tg/DTg methods. The apparent activation energy（E） and pre-exponential constant（A） of the exothermic decomposition stage of gDN were 118.75 kJ/mol and 10^10.86 s^-1, respectively. The critical temperature of the thermal explosion（Tb） of gDN was 164.09 ℃. The specific heat capacity of gDN was determined with the Micro-DSC method and the theoretical calculation method, and the standard molar specific heat capacity was 234.76 J·mol^-1·K^-1 at 298.15 K. The adiabatic time-to-explosion of gDN was also calculated to be a certain value between 404.80 and 454.95 s.

关键词： guanidine dinitramide Ammonium dinitramide Thermal behavior Specific heat capacity Adiabatic time-to-explosion

Theoretical Study on the Mechanism of Sonogashira Coupling Reaction

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Chinese Journal of Structural chemistry 2008年第11期27卷 1404-1411页

作者：陈丽萍洪三国候豪情 department of chemistry College of ScienceNanchang University department of chemistry College of Basic ScienceEast China Jiaotong University College of chemistry and Chemical Engineering Jiangxi Normal University

The mechanism of palladium-catalyzed Sonogashira cross-coupling reaction has been studied theoretically by DFT （density functional theory） calculations. The model system studied consists of pd（pH3）2 as the starting catalyst complex, phenyl bromide as the substrate and acetylene as the terminal alkyne, without regarding to the co-catalyst and base. Mechanistically and energetically plausible catalytic cycles for the cross-coupling have been identified. The DFT analysis shows that the catalytic cycle occurs in three stages： oxidative addition of phenyl bromide to the palladium center, alkynylation of palladium（Ⅱ） intermediate, and reductive elimination to phenylacetylene. In the oxidative addition, the neutral and anionic pathways have been investigated, which could both give rise to cis-configured palladium（Ⅱ） diphosphine intermediate. Starting from the palladium（Ⅱ） diphosphine intermediate, the only identifiable pathway in alkynylation involves the dissociation of Br group and the formation of square-planar palladium（Ⅱ） intermediate, in which the phenyl and alkynyl groups are oriented cis to each other. Due to the close proximity of phenyl and alkynyl groups, the reductive elimination of phenylacetylene proceeds smoothly.

关键词： palladium Sonogashira cross-coupling reaction DFT calculations mechanism

The d-orbital regulation of isolated manganese sites for enhanced oxygen evolution

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Nano Research 2023年第8期16卷 10796-10802页

作者： Xue Bai Jingyi Han Xiaodi Niu Jingqi guan Institute of physical chemistry College of ChemistryJilin University2519 Jiefang RoadChangchun 130021China College of Food Science and Engineering Jilin UniversityChangchun 130062China

Developing transition metal-nitrogen-carbon materials(M-N-C)as electrocatalysts for the oxygen evolution reaction(OER)is significant for low-cost energy conversion *** d-orbital adjustment of M center in M-N-C is beneficial to the improvement of OER ***,we synthesize a single-Mn-atom catalyst based on carbon skeleton(Mn_(1)-N_(2)S_(2)C_(x))with isolated Mn-N_(2)S_(2)sites,which exhibits high alkaline OER activity(η10=280 mV),low Tafel slope(44 mV·dec^(−1)),and excellent *** calculations reveal the pivotal function of isolated Mn-N_(2)S_(2)sites in promoting OER,including the adsorption kinetics of intermediates and activation mechanism of active *** doping of S causes the increase in both charge density and work function of active Mn center,and ortho-Mn_(1)-N_(2)S_(2)C_(x)expresses the fastest OER kinetics due to the asymmetric plane.

关键词： dual-heteroatom coordination Mn1-N_(2)S_(2)C_(x) oxygen evolution reaction(OER) single-atom catalyst theoretical calculation

Inherently hydrophilic mesoporous channel coupled with metal oxide for fishing endogenous salivary glycopeptides and phosphopeptides

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Chinese Chemical Letters 2022年第10期33卷 4695-4699页

作者： Zixing Xu Yonglei Wu Xufang Hu Chunhui Deng Nianrong Sun department of chemistry Fudan UniversityShanghai 200433China department of gastroenterology and Hepatology Zhongshan HospitalFudan UniversityShanghai 200032China School of Chemical Science and Technology Yunnan UniversityKunming 650091China

Both glycosylation and phosphorylation exert crucial rule in multitudinous biological *** in-depth profiling of glycosylation and phosphorylation,a magnetic metal oxide is effectively coupled with inherently hydrophilic mesoporous channels(denoted as Fe_(3)O_(4)@TiO_(2)@mSiO_(2)-TSg).Based on the mechanism of hydrophilic interaction liquid chromatography(HILIC)and metal oxide affinity chromatography(MOAC),the Fe_(3)O_(4)@TiO_(2)@mSiO_(2)-TSg nanomaterial shows high capacity for simultaneously enriching glycopeptides and *** human saliva collected in successive four days as practical biological sample,endogenous glycopeptides and phosphopeptides are efficiently *** gene ontology analysis reveals that the identified endogenous glycopeptides and phosphopeptides participate in diverse molecular functions and biological *** strategy is anticipated to promote variation analysis of salivary post-translational modifications.

关键词： Mesoporous material Hydrophilic interaction liquid chromatography Metal oxide affinity chromatography Human saliva Endogenous phosphopeptides Endogenous glycopeptides

Effect of rgO support on gd@ZnO for UV-visible-light driven photocatalytic organic pollutant degradation

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Journal of Rare Earths 2023年第10期41卷 1525-1531,I0002页

作者： Baskaran palanivel Md Shahadat Hossain Romulo R.Macadangdang Jr. S.Sahaya Jude Dhas Abdullah M.Al-Enizi Mohd Ubaidullah Woo Kyoung Kim Sreedevi gedi S.Ignatius Arockiam department of physics Kings Engineering CollegeSriperumbudurKancheepuram602117Tamil NaduIndia department of Innovation Systems Engineering Graduate School of EngineeringUtsunomiya UniversityYoto 7-1-2Utsunomiya 321-8585Japan College of Allied Health National UniversityManila1008Philippines department of chemistry College of ScienceKing Saud UniversityRiyadh11451Saudi Arabia School of Chemical Engineering Yeungnam UniversityGyeongsan38541Republic of Korea pg and Research department of chemistry GTN Arts CollegeDindigul624005Tamil NaduIndia

In this manuscript,we report the hydrothermally prepared rgO/gd@ZnO nanocomposite for the utilization of photocatalytic Rh B(rhodamine B)dye *** required characterization techniques were carried out to analyse the structural,morphological,chemical,environmental and optical behaviour of the prepared *** efficiency of the prepared nanoparticles was studied by Rh B dye degradation upon UV-Vis-light illumination which reveals that composite catalyst degrades the dye molecule about 91%after 40 min of *** comparing the higher degradation efficiency of the rgO/gd@ZnO nanocomposite with that of ZnO and gd doped ZnO,it reveals a greater reduction of charge carriers'recombination,higher visible-light utilization and higher adsorption *** trapping experiment and recycling test were conducted to study the influence of active radicals for the degradation reaction and to know the stability of the prepared nanocomposite,***,this rgO supported gd doped ZnO nanocomposite can provide a new path way in preparing a highly efficient photocatalyst for organic pollutant degradation at large.

关键词： rgO gd doped ZnO UV-Vis photocatalyst Dye degradation Rare earths

Facile Synthesis of Naphtho[2,3-dJthiazoles, Naphtho[2,3-e]-[1,3,4]thiadiazines and Bis（naphtho[2,3-d]thiazolyl）copper（ll） Derivatives from Heteroylthiosemicarbazides

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Chinese Journal of chemistry 2016年第8期34卷 814-822页

作者： Alaa A. Hassan Nasr K. Mohamed Lamiaa E. Abd EI-Haleem Stefan Brase Martin Nieger chemistry department Faculty of Science Minia University 61519 EI-Minia A. R. Egypt Institute of Organic chemistry Karlsruhe Institute of Technology Fritz-Haber-Weg 6 76131 Karlsruhe Germany Laboratory of Inorganic chemistry Department of Chemistry University of Helsinki P.O.Box55 (A. I. Virtasenaukio 1) 00014 Helsinki Finland

A one step synthesis protocol for the conversion of heteroylthiosemicarbazides and 2,3‐dichloro‐1,4‐naphthoquinone to naphtho[2,3‐ d ]thiazoles, naphtho[2,3‐ e ][1,3,4]thiadiazines as well as bis(naphtho[2,3‐ d ]thiazolyl)copper(II) derivatives is described. The products were conclusively confirmed by single crystal X‐ray analyses. A mechanism for the formation of the products is presented.

关键词： heteroylthiosemicarbazides 2,3‐dichloro‐1,4‐naphthoquinone naphtho[2,3‐d]thiazoles naphtho[2,3‐e]thiadiazines bis(naphtho[2,3‐d]thiazolyl)copper(II) derivatives

Synthesis and Temperature-dependent Electrochemical properties of Boron-doped Diamond Electrodes on Titanium

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Chemical Research in Chinese Universities 2012年第3期28卷 507-510页

作者： DU Li-li SUN Jian-rui CUI Hang LI Hong-dong CUI Tian LIN Hai-bo State Key Laboratory of Superhard Materials Jilin UniversityChangchun 130012P.R.China College of chemistry Jilin UniversityChangchun 130012P.R.China State Key Laboratory of Theoretical and Computational chemistry Institute of Theoretical ChemistryJilin UniversityChangchun 130021P.R.China

On the sand-blasting-treated titanium（Ti） substrate, the boron-doped diamond（BDD） electrodes with a wide potential window were prepared by microwave plasma chemical vapor deposition（MpCVD）. The electrochemi- cal oxidation ratios of phenol at BDD/Ti electrodes at elevated temperatures（from 20 ℃ to 80 ℃） were examined by the chemical oxygen demand（COD） of phenol electrolyte during electrolysis. The results show that the COD removal was increased at high temperatures and the optimized temperature for enhancing the electrochemical oxidation ratio of phenol is 60 ℃. The mechanism for the temperature-dependent electrochemical oxidation ratios of phenol at the electrodes was investigated. The study would be favorable for further improving the performance of BDD/Ti elec- trodes, especially working at high temperatures.

关键词： BDD/Ti electrode Microwave plasma chemical vapor deposition phenol Electrochemical degradation

A nonchlorinated solvent-processed polymer semiconductor for high-performance ambipolar transistors

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National Science Review 2022年第4期9卷 139-147页

作者： Jie Yang Yaqian Jiang Zhiyuan Zhao Xueli Yang Zheye Zhang Jinyang Chen Junyu Li Wei Shi Shuai Wang Yunlong guo Yunqi Liu Beijing National Laboratory for Molecular Sciences Key Laboratory of Organic SolidsInstitute of ChemistryChinese Academy of Sciences School of chemistry and Chemical Engineering Huazhong University of Science and Technology

Ambipolar polymer semiconductors are potentially serviceable for logic circuits, light-emitting field-effect transistors(LFETs) and polymer solar cells(pSCs). Although several high-performance ambipolar polymers have been developed, their optoelectronic devices are generally processed from toxic chlorinated solvents. To achieve the commercial applications of organic FETs(OFETs), the polymers should be processed from nonchlorinated solvents, instead of chlorinated solvents. However, most conjugated polymers show poor solubility in nonchlorinated solvents. It is of great importance to develop ambipolar polymers that can be processed from nonchlorinated solvents. Here, we develop a nonchlorinated solvent processed polymer named poly[7-fluoro-N, N′-di(4-decyltetradecyl)-7′-azaisoindigo-6′,6′′-(thieno[3,2-b]thiophene-2,5-diyl)-7′′′-fluoro-N′′, N′′′-di(4-decyltetradecyl)-7′′-azaisoindigo-6,6′′′-([2,2′′-bithiophene]-5,5′′-diyl)](pITTI-BT) by designing a monomer with a large molar mass. The polymer displays good solubility in p-xylene(pX). Well-aligned films of pITTI-BT are achieved by an off-center spin-coating(SC) method. Based on the high-quality films, the OFETs fabricated from pX solution achieve record ambipolar performance with hole and electron mobilities of 3.06 and2.81 cm~2 V-1s-1, respectively. The combination of nonchlorinated solvents and good alignment process offers an effective and eco-friendly approach to obtain high-performance ambipolar transistors.

关键词： nonchlorinated solvent high performance ambipolar transistor alignment

Effect of silver in thermal treatments of Fe-Mn-C degradable metals:Implications for stent processing

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Bioactive Materials 2022年第6期7卷 30-41页

作者： Sergio Loffredo Sofia gambaro Francesco Copes Carlo paternoster Nicolas giguere Maurizio Vedani Diego Mantovani Laboratory for Biomaterials and Bioengineering Canada Research Chair I in Biomaterials and Bioengineering for the Innovation in SurgeryDepartment of Min-Met-Materials EngineeringResearch Center of CHU de QuebecDivision of Regenerative MedicineLaval UniversityQuebec CityQC G1V 0A6Canada department of Mechanical Engineering Politecnico di MilanoMilan20156Italy National Research Council Institute of Condensed Matter Chemistry and Technologies for Energy CNR-ICMATEGenoa16149Italy Quebec Metallurgy Center CMQ Trois-RivieresQCG9A 5E1Canada

Twinning-induced plasticity(TWIp)steels are considered excellent materials for manufacturing products requiring extremely high mechanical properties for various applications including thin medical devices,such as biodegradable intravascular *** is also proven that the addition of Ag can guarantee an appropriate degradation while implanted in human body without affecting its bioactive *** order to develop an optimized manufacturing process for thin stents,the effect of Ag on the recrystallization behavior of TWIp steels needs to be *** is of major importance since manufacturing stents involves several intermediate recrystallization annealing *** this work,the recrystallization mechanism of two Fe-Mn-C steels with and without Ag was thoroughly investigated by microstructural and mechanical *** was observed that Ag promoted a finer microstructure with a different texture evolution,while the recrystallization kinetics resulted *** presence of Ag also reduced the effectiveness of the recrystallization *** behavior was attributed to the presence of Ag-rich second phase particles,precipitation of carbides and to the preferential development of grains possessing a{111}orientation upon thermal *** prominence of{111}grains can also give rise to premature twinning,explaining the role of Ag in reducing the ductility of TWIp steels already observed in other ***,in vitro biological performances were unaffected by *** findings could allow the design of efficient treatments for supporting the transformation of Fe-Mn-C steels alloyed with Ag into commercial products.

关键词： Twinning Recrystallization Biomaterials Silver Steels