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Theoretical Study on Intermolecular Interactions and Thermodynamic Properties of Dimethylnitroamine Clusters

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Chinese Journal of Chemistry 2002年第3期20卷 629-637页

作者： ju，Xue－Hai XIAO，He－Ming 等 DepartmentofChemistry NanjingUniversityofScienceandTechnologyNanjing210094China

Ab initio SCF and Moller-Plesset correlation correction methods incombination with counterpoise procedure for BSSe correction have be.n applied to the theroeticalstudying of dimethylnitroamine and its dimers and trimers. Three optimized stable dimers and twotrimers have be.n obtained. The corrected binding energies of the most stable dimer and trimer werepredicted to be - 24.68 kJ/mol and - 47.27 kJ/mol, respectively at the MP2/6-31G ~*//HF/6-31G~*level. The proportion of correlated interaction energies to their total interaction energies for allclusters was at least 29.3 percent, and the BSSe of Δe(MP2) was at least 10.0 kJ/mol. Dispersionand/ or electrostatic force were dominant in all clusters. There exist cooperative effects in boththe chain and the cyclic trimers. The vibrational frequencies associated with n―O stretches or wagsexhibit slight red shifts, but the modes associated with the motion of hydrogen atoms of the methylgroup show somewhat blue shifts with respect to those of monomer. Thermodynamic properties ofdimethylnitroamine and its clusters at different temperatures have be.n calculated on the basis ofvibrational analyses. The changes of the Gibbs free energies for the aggregation from monomer to themost stable dimer and trimer were predicted to be 14.37 kJ/mol and 30.40 kJ/mol, respectively, at 1atm and 298.15 K.

关键词： dimethylnitroamine cluster intermolecular interaction ah initio thermodynamic property

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Twist-driven separation of p-type and n-type dopants in single-crystalline.nanowires

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national Science Review 2019年第3期6卷 532-539页

作者： Dong-Bo Zhang Xing-ju Zhao Gotthard Seifert Kinfai Tse junyi Zhu College of nuclear Science and Technology Beijing Normal University Beijing Computational Science Research Center Theoretische Chemie Technische Universit?t Dresden Department of Physics the Chinese University of Hong Kong

The distribution of dopants significantly influences the properties of semiconductors, yet effective modulation and separation of p-type and n-type dopants in homogeneous materials remain challenging,especially for nanostructures. employing a bond orbital model with supportive atomistic simulations, we show that axial twisting can substantially modulate the radial distribution of dopants in Si nanowires(nWs)such that dopants of smaller sizes than the host atom prefer atomic sites near the.nW core, while dopants of larger sizes are prone to staying adjacent to the.nW surface. We attribute such distinct behaviors to the twist-induced inhomogeneous shear strain in nW. With this, our investigation on codoping pairs further reveals that with proper choices of codoping pairs, e.g. B and Sb, n-type and p-type dopants can be well separated along the.nW radial dimension. Our findings suggest that twisting may lead to realizations of p–n junction configuration and modulation doping in single-crystalline.nWs.

关键词： twist codoping nanowire generalized Bloch theorem bond orbital theory

Preparation and evaluation of α-Al2O3 supported lithium ion sieve membranes for Li^+ extraction

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Chinese Journal of Chemical engineering 2020年第9期28卷 2312-2318页

作者： Feng Xue Xiaoxian Zhang Yue.niu Chenhao Yi Shengui ju Weihong Xing College of Chemical engineering Nanjing Tech UniversityNanjing 211816China

Spinel lithium manganese oxide ion-sieves have be.n considered the most promising adsorbents to extract Li^+ from brines and sea ***,we report a lithium ion-sieve which was successfully loaded onto tubular α-Al2 O3 ceramic substrates by dipping crystallization and post-calcination *** lithium manganese oxide Li4 Mn5 O(12)was first synthesized onto tubular α-Al2 O3 ceramic substrates as the ion-sieve precursor(i.e.L-AA),and the corresponding lithium ion-sieve(i.e.H-AA) was obtained after acid *** chemical and morphological properties of the ion-sieve were confirmed by X-ray diffraction(XRD) and scanning electron microscopy(SeM).Both L-AA and H-AA showed characteristic peaks of α-Al2 O3 and cubic phase Li4 Mn5 O(12) and the peaks representing cubic phase could still exist after *** lithium manganese oxide Li4 Mn5 O(12) could be uniformly loaded not only on the surface of α-Al2 O3 ubstrates but also inside the ***,we found that the equilibrium adsorption capacity of H-AA was 22.9 mg·g^-*** 12 h adsorption,the adsorption balance was *** 5 cycles of adsorption,the adsorption capacity of H-AA was 60.88% of the initial adsorption *** process of H-AA adsorption for Li^+correlated with pseudo-second order kinetic model and Langmuir *** thermodynamic parameters regarding enthalpy(△n), Gibbs free energy(△G) and entropy(AS) were *** the dynamic adsorptiondesorption process of H-AA,the H-AA exhibited excellent adsorption performance to Li^+ with the Li^+ dynamic adsorption capacity of 9.74 mg·g^-1 and the Mn^2+dissolution loss rate of 0.99%.After 3 dynamic adsorption-desorption cycles,80% of the initial dynamic adsorption capacity was still kept.

关键词： Lithium α-Al2O3 tube Ion sieve Adsorption Li4Mn5O(12)

Circulation and Heat Flux along the Weste.n Boundary of the.north Pacific

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Journal of Oce.n University of China 2020年第1期19卷 1-12页

作者： ju Xia MA Chao XIOnG Xuejun GUO Yanliang and YU Long College of Oce.n and Atmosphere Sciences Ocean University of ChinaQingdao 266100China The First Institute of Oce.nography MNRQingdao 266061China Laboratory for Regional Oce.nography and numerical Modeling Pilot National Laboratory for Marine Science and TechnologyQingdao 266061China Laboratory for Oce.n and Climate Dynamics Pilot National Laboratory for Marine Science and TechnologyQingdao 266100China

On the basis of the conductivity temperature depth(CTD)observation data off the coast of the Philippines(7.5°–18°n,130°e–the east coast of the Philippines)in the fall of 2005,the water mass distribution,geostrophic flow field,and heat budget are *** water masses are present:the.north Pacific Tropical Surface Water,the.north Pacific Sub-surface Water,the.north Pacific Intermediate Water,and the Antarctic Intermediate Water(AAIW).The previous three corresponded with the.north equatorial Current(neC),the Kuroshio Current(KC),and the Mindanao Current(MC),*** is the source of the Mindanao *** mass transport of neC,KC,and MC is 58.7,15,and 27.95Sv,respectively(relative to 1500db).neC can be balanced by the transport across the whole transect 18°n(31.81 Sv)and 7.5°n(26.11 Sv)but not simply by KC and *** calculation is used to study the heat *** sum,1.45PW heat is transported outwards the observed region,which is much more than that released from the oce.n to the air at the surface(0.05PW).The.net heat lost decreased the water temperature by 0.75℃each month on average,and the trend agreed well with the SST ***,the heat transported by the currents is mainly completed in the upper 500 m.

关键词： north Pacific weste.n boundary currents water mass circulation heat flux

Synergistic effect of lithiophilic Zn nanoparticles and n-doping for stable Li metal anodes

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Journal of energy Chemistry 2022年第2期31卷 439-447页

作者： Lei You Shunlong ju Jianwen Liu Guanglin Xia Zaiping Guo Xuebin Yu Department of Materials Science Fudan UniversityShanghai 200433China Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials Ministry-of-Education Key Laboratory for Synthesis and Applications of Organic Functional MoleculesCollege of Chemistry and Chemical EngineeringHubei UniversityWuhan 430062HubeiChina School of Chemical engineering&Advanced Materials The University of AdelaideAdelaideSA 5005Australia

Li metal is the most ideal anode material for next-generation high energy lithium-ion *** uncontrollable growth of Li dendrites,however,hinders its practical ***,we propose the adoption of Zn nanoparticles uniformly embedded in n-doped carbon polyhedra homogeneously built on carbon cloth(Zn@nC@CC)to prevent the formation of Li *** on theoretical calculation and experimental observation,lithiophilic Zn nanoparticles and n-doping inside of the assynthesized Zn@nC play a synergistic role in enhancing the adsorption capacity with Li,thus resulting in uniform Li deposition and complete suppression of Li ***,the porous n-doped carbon polyhedras uniformly distributed on carbon cloth effectively relieves the volume change of Li upon repeated Li stripping/plating process,which contributes to preserving the structural integrity of the whole electrode and hence enhancing its long-term cycling *** from these synergistic effects,the Li-Zn@nC@CC electrode delivers a prolonged lifespan of over 1200 h at 1 mA cm^(-2) with an areal capacity of 1 mA h cm^(-2) in symmetric cells and high Coulombic efficiencies of 95.4%under an ultrahigh capacity of 12 mA h cm^(-2).Remarkably,Li-Zn@nC@CC//LiFePO_(4) full cells deliver a high reversible capacity of 110.2 mA h g^(-1) at 1 C over 200 cycles.

关键词： Li metal anodes Zn nanoparticles n-doping Synergistic effect

围手术期综合性护理干预在宫外孕手术患者中的应用效果

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四川解剖学杂志 2024年第4期32卷 128-130页

作者：琚英赵奇静彭薛郑州大学第一附属医院妇科郑州450000

目的:探讨围手术期综合性护理干预在宫外孕手术患者中的应用效果.方法:选取2021年4月至2023年12月本院收治的89例宫外孕患者为研究对象.按照干预方式,将其分为实验组(n=45,采用围手术期综合性护理干预)和对照组(n=44,采用常规护理干预)... 详细信息

目的:探讨围手术期综合性护理干预在宫外孕手术患者中的应用效果.方法:选取2021年4月至2023年12月本院收治的89例宫外孕患者为研究对象.按照干预方式,将其分为实验组(n=45,采用围手术期综合性护理干预)和对照组(n=44,采用常规护理干预).比较两组患者手术观察指标、疼痛程度和心理状态、并发症发生情况.结果:实验组患者手术总时长、拔导气管时间、术后住院天数及下床活动时间均短于对照组,差异均有统计学意义(P<0.05);干预后,实验组患者视觉模拟评分法(VAS)、症状自评量表(SCL-90)评分低于对照组,差异均有统计学意义(P<0.05);实验组患者并发症总发生率(3/45,6.67%)低于对照组(10/44,22.73%),差异有统计学意义(P<0.05).结论:将围手术期综合性护理干预应用于宫外孕手术患者,可减轻患者疼痛程度,改善心理状态,降低术后并发症发生概率,加快患者术后康复进程.

关键词：围手术期综合性护理干预宫外孕心理状态并发症发生情况

Responses of n_2O reductase gene.nosZ)-denitrifier communities to long-term fertilization follow a depth patte.n in calcareous purplish paddy soil

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Journal of Integrative Agriculture 2017年第11期16卷 2597-2611页

作者： WAnG Ying-yan LU Sheng-e XIAnG Quan-ju YU Xiu-mei ZHAO Ke ZHAnG Xiao-ping TU Shi-hua GU Yun-fu Department of Microbiology College of ResourceSichuan Agricultural University Soil and Fertilizer Institute Sichuan Academy of Agricultural Sciences

The effect of long-term fertilization on soil denitrifying communities was analysed by measuring the abundance and diversity of the.nitrous oxide （n2O） reductase gene, nosZ. Soil samples were collected from plots of a long-term fertilization experiment established in 1982 in Suining City, China. The fertilizer treatments were.no fertilizer （CK）, three chemical fertilizer （CF） treatments （n, nP, nPK）, manure （M） alone, and manure with chemical fertilizers （nM, nPM, nPKM）. The abundance and diversity of the denitrifying bacteria were assessed by real-time quantitative PCR, terminal restriction fragment length polymorphism （T-RFLP）, and cloning and sequencing of nosZ genes. The diversity and abundance of nosZ-denitrifiers was higher in soil amended with manure and chemical fertilizers （CFM） than in soil amended with CF alone, and the highest in topsoil （0-20 cm）. The.nosZ-denitrifier community composition was more complex in CFM soil than in CF soil： Specific species were detected only in the CFM soil. The abundance of nosZ-denitrifier in the.nPKM treatment was approximately two times higher than that in the CK, n, and nPK treatments. Most of the cloned nosZ sequences were closely related to nosZ sequences from Bradyrhizobiaceae and Rhodospirillaceae in Alphaproteobacteria. Of the measured abiotic factors, soil organic matter correlated significantly with the abundance （P〈0.01）; available phosphorus correlated significantly with the topsoil community composition （P〈0.01）, whereas soil organic matter correlated significantly with the subsoil （20-90 cm） community composition （P〈0.01）. This study demonstrated that long-term CFM fertilization affected both the abundance and composition of the.nosZ-denitrifier community.

关键词： fertilization community abundance denitrifiers soil depth

Influence of the wastewater composition on denitrification and biological P-removal in the S-Dn-P process: (c) Dissolved and undissolved substrates

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Journal of environmental Sciences 2009年第8期21卷 1074-1079页

作者： Hee-jeong Choi Chul-Ho Choi Se.ng-Mok Lee Diwakar Tiwari Department of environmental engineering Kwandong University Department of Chemistry School of Physical Sciences Mizoram University

The denitdfication and P-removal in the sorption-denitrification-P-removal （S-Dn-P） process were carded out under various wastewater compositions. It is noted that P-removal largely depends on the wastewater composition as well to the quantity of the substrates present in wastewater fraction. Three different wastewater fractions are obtained as： raw wastewater, dissolved wastewater （obtained with filtration using 0.45 μm filter）, and undissolved wastewater （i.e., infiltrate obtained by above filtration）. The ratio of P-release/CODtotal-consumption clearly inferred that undissolved wastewater possess very low value i.e., 0.0008 followed by raw wastewater 0.008 and dissolved wastewater 0.03. When this ratio was nearby 0.01, enhanced P-removal was observed. Moreover, the ratio of P-uptake to nO3^--n decomposition for raw wastewater was two times for dissolved wastewater. Interestingly, it was observed that the P-removal and denitrification depend not only on the dissolved substrates but also the undissolved substrates present in the wastewater. The result of the P-removal obtained with this S-Dn-P process did not show a big difference of 36%, 34% and 30%, respectively, for raw, dissolved and undissolved wastewater.

关键词： denitrification polyhydroxybutyrate sequencing batch biofilm reactor sorption denitrification P-removals

Ξbb and Ωbbb molecular states

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Chinese Physics C 2020年第6期44卷 87-94页

作者： J.M.Dias Qi-Xin Yu Wei-Hong Liang Zhi-Feng Sun ju-jun Xie e.Oset m.dias1 2qi-xin yu13wei-hong liang14zhi-feng sun5ju-jun xie6785.oset191.department of physicsguangxi normal universityguilin 541004china instituto de física universidade de são paulorua do matão 1371.butantãcep 05508-090são paulosão paulobrazil institute for experimental physics department of physicsuniversity of hamburgluruper chaussee 149d-22761 hamburggermany guangxi key laboratory of nuclear physics and technology guangxi normal universityguilin 541004china school of physical science and technology lanzhou universitylanzhou 730000china institute of mode.n physics chinese academy of scienceslanzhou 730000china school of physics and microelectronics zhengzhou universityzhengzhou 450001china school of nuclear science and technology university of chinese academy of sciencesbeijing 100049china departamento de física teórica and ific centro mixto universidad de valencia-csic institutos de investigación de paternaaptdo.2208546071 valenciaspain

Using the vector exchange interaction in the local hidden gauge approach,which in the light quark sector generates the chiral Lagrangians and has produced realistic results for Ωc,Ξc,Ξb and the hidden charm pentaquark states,we study the meson-baryon interactions in the coupled channels that lead to the Ξbb and Ωbbb excited states of the molecular *** obtain seven states of the Ξbb type with energies betwe.n 10408 and 10869 MeV,and one Ωbbb state at 15212 MeV.

关键词： doubly-heavy baryons strong interaction molecular state