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Theoretical Investigation of Detailed Thermodynamic Character of Possible Difunctional Adducts Model

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Chinese Journal of Structural Chemistry 2006年第5期25卷 533-542页

作者： CHANG Guan-Ru ZHOU li-Xin chen dong Department of Chemistry Jinan University Guangzhou Guangdong 510632 China

The B3LYP/6-31G^＊ level of theory was used to optimize trans-[Pt（NH3）（Am）G-L], where Am = quinoline or thiazole and L is chosen as the model for functional groups of peptide side chains, and for adenine and guanine sites of DNA as the ultimate target of platinum anticancer drugs. Bond dissociating energy and stability energy of complexes are chosen to study detailedly thermodynamic character of possible difunctional adducts model. In order to investigate the influence of a polarizable environment on the energy of the Pt-L bond formation, we adopt a new bonding energy formula brought forward by lippard and his coworkers： △H（Sol） = △H（SCF）＋ △G（Solv）, which is quite appropriate to compare with what is found in experimental studies. Our calculated results demonstrate that N-containing ligands are more favored in view of thermodynamics both in gas phrase and in solution. However, it is worthly to be noted that addition of solvation free energies result in moderate correction of bonding energy in relative ordering, and the largest ones both present in imidazole ligand, not in guanine ligand. Finally, the nature of bond is analyzed in terms of partial charges distribution based on NBO population.

关键词： nonclassical transplatin antitumor drug difunctional adduct DFT

Impulsive Synchronization of Laser Plasma System

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Communications in Theoretical Physics 2007年第6期47卷 1067-1072页

作者： li Yang liAO Xiao-Feng li Chuan-dong chen Guo Department of Computer Science and Engineering Chongqing University Chongqing 400044 China

The issue of impulsive synchronization of the coupled chaotic laser plasma system is investigated. A new framework for impulsive synchronization of such chaotic systems is presented, which makcs the synchronization error system a linear impulsive control system. We derive some suffcient conditions for the synchronization of a laser plasma system via impulsive control with the varying impulsive intervals, which allows us to derive the impulsive synchronization law easily. To illustrate the effectiveness of the proposed results, two numerical examples are given.

关键词： chaos impulsive stabilization impulsive control impulsive synchronization

Improving thermoelectric properties of ZrPtSn-based half-Heusler compound by Sb doping

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Rare Metals 2021年第10期40卷 2838-2846页

作者： Chu-Kun Dai Qing-Feng Song li Xie Rui-Heng liu Sheng-Qiang Bai li-dong chen State Key Laboratory of High Performance Ceramics and Superﬁne Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Shenzhen Institute of Advanced Electronic Materials Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China

Bipolar diffusion appeared at high temperature leads to the performance deterioration of thermoelectric(TE) materials, and TE materials with large band gaps have high intrinsic excitation temperature, which is important for high-temperature application. Previous calculation has revealed that ZrPtSn half-Heusler has a large band gap(~1.0 eV) among various half-Heusler compounds,which may be a good candidate for thermoelectric generators at high temperature. In this study, the structure and TE properties of Zr PtSn_(1-x)Sb_(x) half-Heusler compounds were studied by optimization of carrier concentration through Sb doping. With 8% Sb substitution at Sn sites, the enhanced power factor of 23 μ W·cm^(-1)·K^(-2) at 850 K and figure of merit(zT) value of 0.5 at 1000 K were reported in n-type ZrPtSn compounds. Further, the effect of Ni alloying in ZrPt_(1-y)Ni_(y)Sn_(0.92)Sb_(0.08) compounds were also investigated. With the strong point defect scattering for phonons,the lattice thermal conductivity is decreased by~40% at room temperature compared with that of unalloyed compounds. However, due to the depressed carrier mobility, the final zT does not show much superiority with ZrPtSn_(0.92)Sb_(0.08) sample.

关键词： Thermoelectric Half-Heusler Band gap Carrier concentration

Long Noncoding RNA UCA1 Overexpression Is Associated with Poor Prognosis in Digestive System Malignancies: A Meta-analysis

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Current Medical Science 2019年第5期39卷 694-701页

作者： Fei-tao SHI li-dong chen lian-feng ZHANG Department of Gastroenterology the First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052China

Long noncoding RNA(IncRNA)urothelial carcinoma associated 1(UCA1)has been reported to be highly expressed in many kinds of *** meta-analysis summarized its potential prognostic value in digestive system malignancies.A meta-analysis was performed through a comprehensive search in PubMed,EMBASE,the Cochrane library,Web of Science and Chinese National Knowledge Infrastructure(CNKI)for suitable articles on the prognostic impact of UCA1 in digestive system malignancies from inception to June 27,*** hazard ratios(HRs)with 95% confidence interval(95%CI)were calculated to summarize the *** studies were included in the study,with a total of 1504 patients.A significant association was observed between UCA1 abundance and poor overall survival(OS),and shorter disease-free survival(DFS)for patients with digestive system malignancies,with pooled HR of 2.07(95%CI:1.74-2.47),and of 2.50(95%CI:1.62-3.86).Subgroup analysis and sensitivity analysis suggested the reliability of our *** is suggested that UCA1 abundance may serve as a reliable predictive factor for poor prognosis in patients with digestive system malignancies.

关键词： long noncoding RNAs urothelial carcinoma associated 1 prognosis digestive system tumor meta-analysis

Low-temperature chlorination roasting technology for the simultaneous recovery of valuable metals from spent liCoO_(2)cathode material

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 80-91页

作者： Junjie Shi Changle Hou Jingjing dong dong chen Jianzhong li Key Laboratory for Ecological Metallurgy of Multimetallic Mineral(Ministry of Education) Northeastern UniversityShenyang 110819China School of Metallurgy Northeastern UniversityShenyang 110819China

With the continuous increase in the disposal volume of spent lithium-ion batteries(liBs),properly recycling spent liBs has become essential for the advancement of the circular *** study presents a systematic analysis of the chlorination roasting kinetics and proposes a new two-step chlorination roasting process that integrates thermodynamics for the recycling of liB cathode *** activation energy for the chloride reaction was 88.41 kJ/mol according to thermogravimetric analysis–derivative thermogravimetry data obtained by using model-free,model-fitting,and Z(α)function(αis conversion rate).Results indicated that the reaction was dominated by the first-order(F1)model when the conversion rate was less than or equal to 0.5 and shifted to the second-order(F2)model when the conversion rate exceeded *** conditions were determined by thoroughly investigating the effects of roasting temperature,roasting time,and the mass ratio of NH_(4)Cl to liCoO_(2).Under the optimal conditions,namely 400℃,20 min,and NH_(4)Cl/liCoO_(2)mass ratio of 3:1,the leaching efficiency of li and Co reached 99.43% and 99.05%,*** of the roasted products revealed that valuable metals in liCoO_(2)transformed into CoCl_(2) and ***,the reaction mechanism was elucidated,providing insights for the establishment of a novel low-temperature chlorination roasting technology based on a crystal structure *** technology can guide the development of liB recycling processes with low energy consumption,low secondary pollution,high recovery efficiency,and high added value.

关键词： spent lithium-ion battery thermodynamics chlorination roasting kinetics circular economy

Preparation of High Surface Area, Large Pore Volume Alumina by Using β-Cyclodextrin as a Non-surfactant Template

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Chinese Chemical Letters 2006年第9期17卷 1239-1242页

作者： Lai Jun WANG Ming Fen WEN Yu Shan li dong YANG Jing chen Chong li SONG Laboratory 201 Institute of Nuclear and New Energy Technology Tsinghua University Beijing 102201

A series of alumina samples were prepared using β-cyclodextrin as the non-surfactant template. These samples were characterized by XRD, BET and TEM. The results showed that the alumina samples prepared using β-cyclodextrin template had the higher surface areas （124-484 m^2/g）, larger pore volumes （0.7-1.27 mL/g） and more thermal stability than samples prepared without using β-cyclodextrin.

关键词： Al2O3 β-cyclodextrin templating method specific surface area.

Improved electrical transport properties and optimized thermoelectric figure of merit in lithium-doped copper sulfides

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Rare Metals 2018年第4期37卷 282-289页

作者： Meng-Jia Guan Peng-Fei Qiu Qing-Feng Song Jiong Yang Du-Di Ren Xun Shi li-dong chen State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of Science Shanghai 200050 China University of Chinese Academy Science Beijing 100049 China Materials Genome Institute Shanghai UniversityShanghai 200444 China

Copper sulfide Cu2S is a p-type semiconducting compound that has attracted great attentions in the thermoelectric （TE） community most recently. Considering the intrinsic ultralow lattice thermal conductivity, the enhancement of TE performance in CuzS should be achieved through improving its electrical transport properties. To achieve this goal, lithium element was doped into CuzS in this study. A series of Cu2_xlixS samples with different li contents （x = 0, 0.005, 0.010, 0.050, and 0.100） was synthesized by the melting-annealing method. When x 〈 0.05, the Cuz_xlixS samples are stable and pure phases, having the same monoclinic structure with the pristine Cu2S at room temperature. The electrical conductivities in the Cu2_xlixS samples are greatly improved with the li-doping content increasing due to the enhanced carrier concentrations. Meanwhile, doping li into CuzS increases the ionic activation energy and lessens the influence of mobile Cu ions on the heat-carrying phonons. Thus, the thermal conductivities of the li-doped Cu2S samples increase. A maximal figure of merit （zT） of 0.84 at 900 K is obtained in Cul.99lio.018, about 133% improvement as compared with that in Cu2S matrix.

关键词： Thermoelectric Copper sulfide Doping Superionic conductor

Anion-site-modulated thermoelectric properties in Ge2Sb2Te5-based compounds

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Rare Metals 2020年第10期39卷 1127-1133页

作者： Ping Hu Tian-Ran Wei Shao-Ji Huang Xu-Gui Xia Peng-Fei Qiu Jiong Yang li-dong chen Xun Shi State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China Materials Genome Institute Shanghai UniversityShanghai 200444China

The amalgamation of multi-subjects often elicits novel materials,new concepts and unexpected ***,Ge2 Sb2 Te5,as the most established phasechange material,has been found to exhibit decent thermoelectric performance in its stable,hexagonal *** challenge for higher figure of merit(zT) values lies in reducing the hole carrier concentration and enhancing the Seebeck coefficient,which,however,can be hardly realized by conventional *** in this work,we report that the electrical properties of Ge2 Sb2 Te5 can be readily optimized by anion-site ***,Se/S substitution for Te induces stronger and more ionic bonding,lowering the hole ***,an increase in electronic density of state is introduced by Se substitution,contributing to a large increase in Seebeck *** with the reduced thermal conductivity,maximum zT values above 0.7 at 800 K have been achieved in Se/S-alloyed materials,which is ~30% higher than that in the pristine Ge2Sb2 Te5.

关键词： Thermoelectric Ge2Sb2Te5 Anion-site modulation Chemical bond Electronic density of states

The Closeness of the τ-Standard Part of a Set

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Journal of Mathematical Research and Exposition 2011年第2期31卷 371-376页

作者： dong li chen Jing Jing FENG Chun Hui MA School of Science Xi'an University of Architecture and Technology Shaanxi 710055 P. R. China Department of Basic Courses Xi'an Peihua University Shaanxi "710125 P. R. China

In this paper,the closeness of the τ-standard part of a set is *** related propositions of the τ-neighborhood system of a set are *** then some related conclusions of the τ-monad of a set and the τ-standard part of a set are *** based on it,the necessary and sufficient conditions of the enlarged model and the saturated model are ***,some sufficient conditions that the τ-standard part of a set is closed are proved in the enlarged model and the saturated model.

关键词： enlarged models saturated models τ-standard part τ-closed set