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Electron transport properties of boron-doped capped-carbon-nanotube-based molecular junctions

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science Bulletin 2010年第36期55卷 4104-4107页

作者： zhao peng1 & liu desheng2 1 school of science, university of jinan, jinan 250022, china 2 school of Physics, State Key Laboratory of Crystal Materials, Shandong university, jinan 250100, china school of science University of Jinan Jinan 250022 China school of Physics State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China

Using the Landauer formalism that combines both the non-equilibrium Green’s function and first-principles density functional theory, the electron transport properties of a one-dimensional molecular junction based on capped carbon nanotubes with boron doping at various sites are investigated. The results show that the electron transport properties are strongly dependent on the boron-doping site. Negative differential resistance behavior can be observed when boron-atom dopants are present in the tip region.

关键词： carbon nanotube doping non-equilibrium Green’s function density functional theory

Negative differential resistance in molecular devices: the role of molecule-electrode coupling

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science china(Physics,Mechanics & Astronomy) 2011年第8期Mechanics & Astronomy) .卷 1455-1460页

作者： ZHAI YaXin1, JI GuoMin1, FANG ChangFeng1, CUI Bin1, zhao peng2 & liu desheng1,3, 1 school of Physics, State Key Laboratory of Crystal Materials, Shandong university, jinan 250100, china 2 school of science, university of jinan, jinan 250022, china 3 Department of Physics and Information Engineering, Jining university, Qufu 273100, china 1. school of Physics State Key Laboratory of Crystal Materials Shandong University Jinan 250100 China2. School of Science University of Jinan Jinan 250022 China3. Department of Physics and Information Engineering Jining University Qufu 273100 China

By applying nonequilibrium Green's function formalism combined with the first-principles density functional theory, we investigate the electronic transport in two molecular junctions constituted by a substituted oligo (phenylene ehtynylene) sand-wiched between two Au electrodes. Our calculations show that the weak molecule-electrode coupling is responsible for the observation of the negative differential resistance (NDR) effect in experiments. When the coupling is weak, the projected density of states (PDOS) of the molecule and the electrodes undergoes a mismatch-match-mismatch procedure, which increases and then decreases the transmission peak intensities, leading to a NDR effect. We also find that the localization/delocalization of the molecular orbitals and the change of charge state of the molecule have no direct relation with the NDR effect, because they change little as the voltage increases.

关键词： negative differential resistance substituted oligo (phenylene ehtynylene) molecular junction density functional theory nonequilibrium Green’s function formalism

Direct ink writing of multifunctional gratings with gel-like MXene/norepinephrine ink for dynamic electromagnetic interference shielding and patterned Joule heating

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Nano Research 2024年第3期17卷 1585-1594页

作者： Pei-Zhu Jiang Zhiming Deng peng Min Lvxuan Ye Cheng-zhang Qi Hao-Yu zhao Ji liu Hao-Bin zhang zhong-Zhen Yu Beijing Key Laboratory of Advanced Functional Polymer Composites Beijing University of Chemical TechnologyBeijing 100029China State Key Laboratory of Organic-Inorganic Composites College of Materials Science and EngineeringBeijing University of Chemical TechnologyBeijing 100029China school of Chemistry CRANN and AMBERTrinity College DublinDublin D02PN40Ireland

Intelligent electromagnetic interference(EMI)shielding modulators with a wide tuning range and cyclic stability are urgently needed but their fabrication remains challenging.A gel-like MXene/norepinephrine ink is developed and multifunctional MXene gratings with wide EMI shielding effectiveness(SE)tuning range,superior reversibility,and high mechanical flexibility are constructed by direct ink writing approach for dynamic EMI shielding and patterned Joule heating *** modulable MXene/norepinephrine grating with a high conductivity of 3510 S·cm-1 can conveniently realize the seamless modulation of the EMI SE by adjusting the angle between the MXene grating filaments and the electric field of the incident electromagnetic waves,offering highly reversible switching between shielding“On”(28.0 dB)and“Off”(0.5 dB)***,due to the optimized integration of the MXene ink and the rationally designed pattern,a superior specific EMI SE of 95,688.2 dB·cm^(2)·g^(-1) is achieved in the“On”***,the MXene/norepinephrine ink can be used to fabricate many complex patterned gratings with superior stability,instant responsibility,and superb mechanical flexibility,exhibiting a unique patterned Joule heating *** writing of multifunctional gratings paves a means for developing intelligent EMI shielding materials,wearable electronic devices,and advanced thermal management materials.

关键词： MXene ink direct ink writing electromagnetic interference shielding multifunctional gratings Joule heating

Tim4 deficiency reduces CD301b+macrophage and aggravates periodontitis bone loss

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International Journal of Oral science 2024年第2期16卷 280-292页

作者： Ziming wang Hao Zeng Can wang Jiaolong wang Jing zhang Shuyuan Qu Yue Han liu Yang Yueqi Ni Wenan peng Huan liu Hua Tang Qin zhao Yufeng zhang State Key Laboratory of Oral&Maxillofacial Reconstruction and Regeneration Key Laboratory of Oral Biomedicine Ministry of EducationHubei Key Laboratory of StomatologySchool&Hospital of StomatologyTaikang Center for Life and Medical SciencesWuhan UniversityWuhanChina school of Stomatology Nanchang UniversityNanchangChina Institute of Infection and Immunity Science and Technology Innovation CenterShandong First Medical University&Shandong Academy of Medical SciencesJinanChina Medical Research Institute School of MedicineWuhan UniversityWuhanChina

Periodontitis is a common chronic inflammatory disease that causes the periodontal bone destruction and may ultimately result in tooth *** the progression of periodontitis,the osteoimmunology microenvironment in periodontitis is damaged and leads to the formation of pathological alveolar bone ***301b^(+)macrophages are specific to the osteoimmunology microenvironment,and are emerging as vital booster for conducting bone ***,the key upstream targets of CD301b^(+)macrophages and their potential mechanism in periodontitis remain *** this study,we concentrated on the role of Tim4,a latent upstream regulator of CD301b^(+)*** first demonstrated that the transcription level of Timd4(gene name of Tim4)in CD301b^(+)macrophages was significantly upregulated compared to CD301b^(-) macrophages via high-throughput RNA ***,several Tim4-related functions such as apoptotic cell clearance,phagocytosis and engulfment were positively regulated by CD301b^(+)*** single-cell RNA sequencing analysis subsequently discovered that Cd301b and Timd4 were specifically co-expressed in *** following flow cytometric analysis indicated that Tim4 positive expression rates in total macrophages shared highly synchronized dynamic changes with the proportions of CD301b^(+)macrophages as periodontitis ***,the deficiency of Tim4 in mice decreased CD301b^(+)macrophages and eventually magnified alveolar bone resorption in ***,Tim4 controlled the p38 MAPK signaling pathway to ultimately mediate CD301b^(+)macrophages *** a word,Tim4 might regulate CD301b^(+)macrophages through p38 MAPK signaling pathway in periodontitis,which provided new insights into periodontitis immunoregulation as well as help to develop innovative therapeutic targets and treatment strategies for periodontitis.

关键词： period upstream eventually

Structure-based design and optimization lead to the identification of novel dihydrothiopyrano[3,2-d]pyrimidine derivatives as potent HIV-1 inhibitors against drug-resistant variants

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Acta Pharmaceutica Sinica B 2024年第3期14卷 1257-1282页

作者： zhao wang Heng zhang Zhen Gao Zihao Sang Erik De Clercq Christophe Pannecouque Dongwei Kang peng Zhan Xinyong liu Department of Medicinal Chemistry Key Laboratory of Chemical Biology(Ministry of Education)School of Pharmaceutical SciencesCheeloo College of MedicineShandong UniversityJinan 250012China Rega Institute for Medical Research Laboratory of Virology and ChemotherapyK.U.LeuvenLeuven B-3000Belgium china-Belgium Collaborative Research Center for Innovative Antiviral Drugs of Shandong Province Jinan 250012China Suzhou Research Institute Shandong UniversitySuzhou 215123China

With our continuous endeavors in seeking potent anti-HIV-1 agents,we reported here the discovery,biological characterization,and druggability evaluation of a class of nonnucleoside reverse transcriptase *** fully explore the chemical space of the NNRTI-binding pocket,novel series of dihydrothiopyrano[3,2-d]pyrimidines were developed by employing the structure-based design *** of the derivatives were endowed with prominent antiviral activities against HIV-1 wild-type and resistant strains at nanomolar *** them,compound 23h featuring the aminopiperidine moiety was identified as the most potent inhibitor,with EC50values ranging from 3.43 to 21.4 nmol/***,for the challenging double-mutants F227L+V106A and K103N+Y181C,23h exhibited 2.3-to 14.5-fold more potent activity than the first-line drugs efavirenz and ***,the resistance profiles of 23h achieved remarkable improvement compared to efavirenz and *** binding target of 23h was further confirmed to be HIV-1 reverse *** modeling studies were also performed to elucidate the biological evaluation results and give guidance for the optimization ***,no apparent inhibition of the major CYP450 enzymes and hERG channel was observed for *** importantly,23h was characterized by good pharmacokinetic properties and excellent safety in ***,23h holds great promise as a potential candidate for its effective antiviral efficacy and favorable drug-like profiles.

关键词： HIV-1 Reverse transcriptase Dihydrothiopyrano[3,2-d]pyrimidine Antiviral agent

Stretchable and environment-resistant doubly crosslinked hydrogel for all-in-one supercapacitor and strain sensors

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Journal of Materiomics 2024年第6期10卷 1186-1195页

作者： Chunlin liu Le Jjiang Fenglin zhao Qin Hu Yingge zhang Xiaodan Sun Lianxin peng school of Mechanical Engineering Chengdu UniversityChengdu 610106China Key Laboratory of Advanced Materials of Ministry of Education of china School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Key Laboratory of Coarse Cereal Processing of Ministry of Agriculture and Rural Affairs Chengdu UniversityChengdu 610106China

Despite their importance as components for flexible electronics,most stretchable hydrogels suffer from incomplete recovery after deformation,are prone to failure upon long-term repeated stretching,and cannot be exploited at subzero temperatures because of the freezing of their constituent ***-quently,strategies for circumventing these drawbacks are highly sought *** study describes the synthesis of a doubly(chemically and physically)crosslinked hydrogel from gelatin and methacrylic acid and demonstrates the suitability of this material for the fabrication of high-performance stretchable and environment-resistant supercapacitors and strain *** performance of this supercapacitor(areal capacitance=1,210.2 mF/cm^(2) at a current density of 1 mA/cm^(2),maximum energy density=158.8μW.h/cm^(-1),maximum power density=659.5μW/cm^(2))was superior to that of most of integrated super-capacitors reported to date and was hardly affected by stretchable,low temperatures,bending,ice-cold water and strong acid/alkali solutions or long-term ***,a strain sensor based on the above hydrogel was capable of accurately capturing human body motions when affixed to skin and recognising mouse movement(even in humid environments)after implantation into mouse *** work may pave the way to high-performance stretchable and environment-resistant wearable electronics.

关键词： Doubly crosslinked hydrogel Stretchable Environment-resistant All-in-one supercapacitor Strain sensor

Magnetic, dielectric and luminescence synergetic switchable effects in molecular material [Et_(3)NCH_(2)Cl]_(2)[MnBr_(4)]

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Chinese Chemical Letters 2024年第4期35卷 502-505页

作者： Yan Cheng Hua-peng Ruan Yan peng Longhe Li Zhenqiang Xie Lang liu Shiyong zhang Hengyun Ye zhao-Bo Hu Chaotic Matter science Research Center Faculty of Materials Metallurgy and ChemistryJiangxi University of Science and TechnologyGanzhou 341000China College of Materials and Chemical Engineering Pingxiang UniversityPingxiang 337055China Jiangxi Provincial Key Laboratory of Functional Molecular Materials Chemistry Jiangxi University of Science and TechnologyGanzhou 341000China Key Laboratory of Jiangxi university for Functional Materials Chemistry School of Chemistry and Chemical EngineeringGannan Normal UniversityGanzhou 341000China

The application of multifunctional materials in various fields such as electronics and signal processors has attracted massive attention. Herein, a new organic-inorganic hybrid material [Et_(3)NCH_(2)Cl]_(2)[MnBr_(4)](1) is reported, which contains two organic amines cations and one [MnBr_(4)] tetrahedral ion. Compound 1 has a dielectric anomaly signal at 338 K, which proves its thermodynamic phase transition. The single crystal measurements at 200 K and 380 K show that the phase transition of compound 1 is caused by the thermal vibration of organic amine cations in the lattice. Moreover, compound 1 shows yellow-green luminescence under UV light irradiation. The magnetism measurements indicate that compound 1 shows switchable magnetic properties. This organic–inorganic material is a multifunctional material with dielectric, optical, and magnetic synergetic switchable effects, which expands a new direction for designing multifunctional materials.

关键词： Synergetic switchable effects Molecular materials Magnetism Dielectric Luminescence

Strategies for improving extraction capacity through preorganization structure:A novel 5,6-bicyclicmalonamide extractant(THPPD)

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Journal of Rare Earths 2024年第4期42卷 768-774页

作者： Miaomiao zhang Zhen Yang Yuhua Cui Jianhui Su Heng zhao Chengjin Xu Xiaolei liu Guoxin Sun Xiujing peng Yu Cui school of Chemistry and Chemical Engineering University of JinanJinan250022China Institute for Smart Materials&Engineering University of JinanJinan250022China Shandong Institute for Food and Drug Control Jinan250101China

Rational design of extractant structure to improve the extraction and separation capacity of rare earth elements(REEs)is a long-standing ***,a new strategy was proposed to improve the stability of the chelating structure formed by malonamide and *** stability of the chelating structure is greatly improved by using a double-ring framework structure which makes the two carbonyl groups of malonamide unable to rotate freely and both of them point to the metal ion *** benzyl groups were used to construct the hydrophobicity of the extractant and the organic shell of the extracted ***-pyrrolo-pyridine-dione(THPPD)was designed and *** structure reduces the energy consumed by rotating carbonyl group in the coordination with metal ions and then improves the extraction ability of *** crystal structure was preorganized as expected,with the two carbonyls pointing in a favorable coordination direction to the structural complement of the metal *** extraction behaviors of REEs with THPPD in a nitric acid medium were *** with N,N’-dibenzyl-N,N’-dimethylmalonamide(DBDM-MA)with a chain structure,the extraction capacity of THPPD is 360 times higher than that of DBDM-MA at 5.0 mol/L sodium ***,the binding energy and Gibbs free energy were investigated by density functional theory(DFT)in conjunction with the *** theoretical results show that THPPD has more effective interaction with Pr(NO_(3))3 than *** construction of chelating groups conformation is a worthy direction to improve the coordination ability and even selectivity of extractant.

关键词： Rare earth elements Extraction separation 5,6-bicyclicdiamide extractant

Ancient mitochondrial genome depicts sheep maternal dispersal and migration in Eastern Asia

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Journal of Genetics and Genomics 2024年第1期51卷 87-95页

作者： liu Yang Xing zhang Yaning Hu Piao Zhu Hua Li Zhenyu peng Hai Xiang Xinying Zhou Xingbo zhao National Engineering Laboratory for Animal Breeding Key Laboratory of AnimalGeneticsBreeding and ReproductionMinistry of Agriculture and Rural AffairsCollege of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China Guangdong Provincial Key Laboratory of Animal Molecular Design and Precise Breeding School of Life Science and EngineeringFoshan UniversityFoshanGuangdong 528225China State Key Laboratory of Agricultural Genomics BGI-ShenzhenShenzhenGuangdong 518083China Key Laboratory of Vertebrate Evolution and Human Origins Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China

Sheep have been one of the most important groups of animals since ancient ***,the knowledge of their migration routes and genetic relationships is still poorly *** investigate sheep maternal migration histories alongside Eurasian communications routes,in this study,we obtain mitochondrial genomes(mitogenomes)from 17 sheep remains in 6 Chinese sites and 1 Uzbekistan site dated 4429–3100 years before present(BP).By obtaining the mitogenomes from the sheep(4429–3556 BP)found in the Tongtian Cave site in Xinjiang,Altai region of northwest china,our results support the emergence of haplogroup C sheep in Xinjiang as early as 4429–3556 *** combined phylogenetic analyses with extant ancient and modern sheep mitogenomes suggest that the Uzbekistan-Altai region may have been a migration hub for early sheep in eastern *** least two migration events have taken place for sheep crossing Eurasia to china,one passing by Uzbekistan and Northwest china to the middle and lower reaches of the Yellow River at approximately 4000 BP and another following the Altai region to middle Inner Mongolia from 4429 BP to 2500 ***,this study provides further evidence for early sheep utilization and migration patterns in Eastern Asia.

关键词： Sheep Ancient DNA Eastern Asia Mitochondrial genome Migration Altai