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Nano Research 2022年第6期15卷 5705-5711页

作者： Wei-Xing Chen Nikolay v.Tkachenko Alvaro Muñoz-Castro alexander I.Boldyrev Zhong-Ming Sun State Key Laboratory of Elemento-Organic Chemistry Tianjin Key Lab of Rare Earth Materials and ApplicationsSchool of Materials Science and EngineeringNankai UniversityTianjin 300350China Department of Chemistry and Biochemistry Utah State University0300 Old Main HillLoganUT 84322-0300USA Grupo de Química Inorgánicay Materiales Moleculares Facultad de IngenieriaUniversidad Autonoma de ChileEl Llano SubercaseauxSantiago 2801Chile

In this work,we report the synthesis and characterization of two novel Ru-containing Zintl clusters:[Sn_(19){Ru(COD)(en)}_(2)]^(4−)and[Sn_(20){Ru(COD)}_(2)]^(6−).The synthesized compounds not only expand the family of Ru-Sn cluster systems but also shed light on the structure of heterometallic complexes in a previously unknown range of tin *** single-crystal X-ray diffraction(XRD)analysis reveals the dimeric nature of the *** different assembly patterns of the formal[Sn(η^(3)-Sn_(9))]monomer were observed:the dimerization through the vertex fusion process and the direct dimerization through the formation of 2c–2e Sn–Snσ*** both clusters,the density functional theory calculations reveal the locallyσ-aromatic nature of the[Sn(η^(3)-Sn_(9))]monomer resulting in two independent magnetic shielding *** believe that our findings will help the community to further explore the fascinating chemistry of polystannide clusters.

关键词： heterometallic clusters aromaticity polystannide ruthenium Zintl anion

Increased paracellular permeability of tumor-adjacent areas in 1,2-dimethylhydrazine-induced colon carcinogenesis in rats

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Cancer Biology & Medicine 2018年第3期15卷 251-259页

作者： viktoria v.Bekusova Evgeny L.Falchuk Larisa S.Okorokova Natalia M.Kruglova alexander D.Nozdrachev alexander G.Markov Department of Physiology St.Petersburg State University I.P.Pavlov Institute of Physiology Russian Academy of Sciences

Objective: The morphology and functions of the proximal and distal large intestine are not the same. The incidence of colorectal cancer in these regions is also different, as tumors more often appear in the descending colon than in the ascending *** bowel disease and colorectal cancer can increase transepithelial permeability, which is a sign of reduced intestinal barrier function. However, there is not enough evidence to establish a connection between the difference in colorectal cancer incidence in the proximal and distal colon and intestinal permeability or the effects of carcinogenesis on the barrier properties in various areas of the colon. The aim of the study was to assess the permeability of different segments of the large intestine according to a developed mapping methodology in healthy rats and rats with 1,2-dimethylhydrazine(DMH)-induced colon ***: The short circuit current, the transepithelial electrical resistance and the paracellular permeability to fluorescein of large intestine wall of male Wistar rats were examined in the Ussing chambers. The optical density of the solution from the serosa side to assess the concentration of the diffused fluorescein from mucosa to serosa was analyzed by spectrophotometry. The morphometric and histological studies were performed by optical ***: Rats with DMH-induced colon adenocarcinomas showed elevated transepithelial electrical resistance in the areas of neoplasm development. In contrast, there was no change in the electrophysiological properties of tumor adjacent areas, however,the paracellular permeability of these areas to fluorescein was increased compared to the control rats and was characterized by sharply reduced barrier ***: The barrier properties of the colon vary depending on tumor location. The tumors were less permeable than the intact intestinal wall and probably have a negative influence on tumor-adjacent tissues by disrupting their bar

关键词： Rat 1,2-dimethylhydrazine colorectal cancer Ussing chamber short circuit current transepithelial electrical resistance intestinal permeability

Multilayers with high-reflectivity at 19.5 nm and low-reflectivity at 30.4 nm

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Chinese Optics Letters 2013年第13期11卷 154-157页

作者：蒋励朱京涛张众王占山 Michael Trubetskov alexander v. Tikhonravov Department Institute of Precision Optical Engineering Department of Physics Tongji University Shanghai 200092 China Lomonosov Moscow State University Russia

The multilayer （ML） mirror with high-reflectivity （HR） at a specific emission line of 19.5 nm （Fe line） and low-reflectivity （LR） at 30.4 nm （He line） is needed to be designed and fabricated for observing the image of sun. Based on a variety of optimizations utilized different structures, the design is performed and the final results demonstrate that the reflectivity at 30.4 nm does not achieve minimum value when the reflectivity at 19.5 nm reaches the maximum value. The tradeoff should be done between the HR at 19.5 nm and LR at 30.4 nm. One optimized mirror is fabricated by direct current magnetron sputtering and characterized by grazing-incident X-ray diffraction （XRD） and synchrotron radiation （SR）. The experimental results demonstrate that the ML achieves the reflectivity of 33.3% at 19.5 nm and of 9.6× 10-4 at 30.4 nm at the incident angle of 13°.

关键词： Reflection

Synthesis and Structure of Binary Copper/Silver-Arsenic Clusters Derived from Zintl Ion As_(7)^(3-)

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Chinese Journal of Chemistry 2022年第1期40卷 65-70页

作者： Wei-Qiang Zhang Nikolay v.Tkachenko Lei Qiao alexander I.Boldyrev Zhong-Ming Sun State Key Laboratory of Elemento-Organic Chemistry Tianjin Key Lab for Rare Earth Materials and ApplicationsSchool of Materials Science and EngineeringNankai UniversityTianjin 300350China Department of Chemistry and Biochemistry Utah State University 0300 Old Main HillLoganUT 84322-0300USA

Polyarsenides containing coinage metals,[As_(7)Cu(PPh_(3))]^(2-)(1)and[M_(2)As_(14)]^(4-)(M=Cu,2;Ag,3),were synthesized by reactions of the nominal composition K_(3)As_(7) with Group 11 metal *** possible intermediate,cluster 1,was isolated from the solution phase through subtle changes in reaction conditions in the formation process of complex ***,we establish the pathway of the bimetallic bridged clusters[Cu_(2)As_(14)]^(4-)by the oxidation of the[As_(7)Cu(PPh_(3))]^(2-).Quantum chemical calculations reveal the presence of metallophilic interaction in clusters 2 and 3.

关键词： Polyarsenide cluster Reaction mechanism Zintl ions Covalently bound Metallophilic interaction

NMR chemical shifts of carbon atoms and characteristic shift ranges in the oil sample

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Petroleum Research 2022年第2期7卷 269-274页

作者： Ilfat Z.Rakhmatullin Sergej v.Efimov alexander v.Klochkov Oleg I.Gnezdilov Mikhail A.varfolomeev vladimir v.Klochkov Kazan Federal University 18 Kremlevskaya St.Kazan420008Russian Federation

Application of high resolution^(13)C nuclear magnetic resonance(NMR)spectroscopy to characterize crude oil was *** chemical shifts of^(13)C NMR functional groups that determine the composition of the oil sample were *** fractions of primary,secondary,quaternary,tertiary,aromatic groups,aromatic factor and average hydrocarbon chain length of aliphatic hydrocarbons of the oil sample according to^(13)C NMR spectra were *** description of the^(13)C NMR spectra of the oil sample using a single consideration of three NMR spectra:^(13)C,^(13)C Attached Proton Test(APT),^(13)C with Gated Decoupling(GD)was *** different contribution of the studied oil sample in the aliphatic(10e75 ppm)and aromatic(115e165 ppm)areas of the^(13)C NMR spectra was *** presence of all major hydrocarbon components in the studied oil sample was established on the quantitative level,the aromaticity factor and the mean length of the hydrocarbon chain were *** fractions of aromatic molecules and functional groups constituting oil hydrocarbons were *** this work we demonstrate that the attached proton test and gated decoupling^(13)C NMR spectroscopy can afford all information to complete the chemical shift assignment of an oil sample,especially for determination of long range 1He^(13)C coupling constants and^(13)C multiplicity.

关键词： ^(13)C NMR spectroscopy Crude oil Oil fraction Functional group Qualitative analysis Quantitative composition Aromaticity Attached proton test Gated decoupling

The effects of social distancing and self-isolation on functional outcomes after radical prostatectomy during the coronavirus disease 2019(COvID-19)pandemic

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Current Urology 2022年第2期16卷 65-69页

作者： Bara Barakat Samer Schakaki Thomas-alexander vögeli Department of Urology and Pediatric Urology Hospital ViersenViersenGermany Department of Urology Hospital OsnabrückOsnabrückGermany Department of Urology and Pediatric Urology University Hospital RWTH AachenAachenGermany

Background:This study is aimed to analyze the effect of social distancing on functional outcomes(potency,continence recovery,and quality of life)on patients undergoing open radical prostatectomy(ORP)and robot-assisted radical prostatectomy(RARP)during the coronavirus disease 2019(COvID-19)*** and methods:We retrospectively assessed functional outcomes of 55 consecutive patients who underwent radical prostatectomy during the COvID-19 pandemic(group A:12 ORP and 15 RARP)and compared these data with patients from the previous year(group B:13 ORP and 15 RARP).Propensity-score matching was performed to analyze variables associated with potency,continence recovery and compared between the groups at 1 and ***:Patients from group A were less interested in postsurgical rehabilitation compared to those from group B(95.7%vs.56.2%,p=0.042).Continence recovery among group B patients also tended to be higher for RARP(p=0.06)and ORP(p=0.08)at 1 month,although statistical significance was not *** cumulative continence recovery at 3months among group B patients was higher and statistically significantly advantageous for RARP(p=0.00)and ORP(pve-sparing procedures were statistically significantly advantageous for RARP(p=0.026)and ORP(p=0.011).Conclusions:Our results highlight the large impact of the COvID-19 pandemic on functional outcomes following radical *** design and planning of home-based models for improved post-operative care should consider this evidence.

关键词： COvID-19 Open and robot-assisted radical prostatectomy Potency Urinary incontinence

Changes of the Molecular Mobility of Poly(ε-caprolactone) upon Drawing,Studied by Dielectric Relaxation Spectroscopy

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Chinese Journal of Polymer Science 2018年第5期36卷 665-674页

作者： Xiao-Yan Yang Shao-Shuai Liu alexander v.Korobko Stephen J.Picken Nicolaas A.M.Besseling Lucky Research Institute China Lucky Group Corporation Department of Chemical Engineering Delft University of Technology 2628 BL Delft and Dutch Polymer Institute(DPI)

Dielectric relaxation spectroscopy（DRS） of poly（ε-caprolactone） with different draw ratios showed that the mobility of polymer chains in the amorphous part decreases as the draw ratio increases. The activation energy of the α process, which corresponds to the dynamic glass transition, increases upon drawing. The enlarged gap between the activation energies of the α process and the β process results in a change of continuity at the crossover between the high temperature a process and the α and β processes. At low drawing ratios the a process connects with the β process, while at the highest drawing ratio in our measurements, the a process is continuous with the αprocess. This is consistent with X-ray diffraction results that indicate that upon drawing the polymer chains in the amorphous part align and densify upon drawing. As the draw ratio increases, the α relaxation broadens and decreases its intensity, indicating an increasing heterogeneity. We observed slope changes in the α traces, when the temperature decreases below that at which τα≈ 1 s. This may indicate the glass transition from the ‘rubbery＇ state to the non-equilibrium glassy state.

关键词： Semicrystalline polymer Dielectric relaxation spectroscopy Molecular mobility

Spatial avoidance of patches of polluted chernozem soils by soil invertebrates

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Insect Science 2009年第1期16卷 99-105页

作者： Konstantin B. Gongalsky Svetlana A. Belorustseva Daria M. Kuznetsova alexander v. Matyukhin Lyubov A. Pelgunova Fyodor A. Savin alexander S. Shapovalov A.N. Severtsov Institute of Ecology and Evolution Russian Academy of Sciences Moscow Department of Invertebrate Zoology Faculty of Biology Moscow State University Moscow Department of Biogeography Faculty of Geography Moscow State University Moscow and 4Belogorye Nature Reserve Monastyrsky pereulok Borisovka Belgorod Region Russian Federation

Soil invertebrates and heavy metal concentrations are heterogeneously distributed in the soil of steppe plots surrounding an iron mining enterprise in southern Russia. This study assesses whether patches of high soil invertebrate abundance coincide with patches of low concentrations of pollutants. For this aim, spatial analysis by distance indices （SADIE） was applied. Three valleys in Belogorye Nature Reserve were chosen. One valley faced the tailing pond to the north and the other two faced south-east or south-west. Two sampling plots were chosen in each valley, 60 m apart from each other. On every plot 16 soil cores were collected from a grid of 4 × 4 units with a 5-m distance between each sample unit. Each soil core had an area of 76 cm2 and was 12-15 cm deep. All macroinvertebrates were hand-sorted and identified to family. Abundance of soil invertebrates was not controlled by patches of metal concentration in the soil. Epigaeic groups, like insects and other invertebrates inhabiting the litter layer, were not directly associated with local parameters of the soil. On the contrary, belowground invertebrate abundance （elaterid larvae and earthworms） showed significant dissociation with some heavy metal （Fe, Pb, Zn） concentrations in the soil. The patchiness of soil pollution may act as a leading factor ofbelowground soil invertebrate distribution. The spatial structure of animal populations in industrially transformed soils needs further research.

关键词： invertebrates macrofauna SADIE soil pollution spatial distribution

New look at territories of traditional nature use–traditional nature management lands at the coastal zone of the Ice Silk Road:a case study for the Russian Arctic

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International Journal of Digital Earth 2019年第8期12卷 948-961页

作者： alexander v.Evseev Tatiana M.Krasovskaya vladimir S.Tikunov Irina N.Tikunova Geographical Faculty Lomonosov Moscow State UniversityMoscowRussia

Territories of traditional nature use(TTNU)of indigenous population in the Arctic zone presents a historical model of sustainable development whose main principles are valuable for modern practice of economic activities in this region as *** peoples traditional nature management practice in the Russian Arctic nowadays exists only within tribal community lands,though their virtual limits may be larger and known to indigenous population,helping to preserve regional *** of TTNU in the course of modern economic development,including the Northern Silk Road coastal infrastructure,is important for regional ecological and social *** may be regarded as ecological buffer zones,restoring ecosystem functions important for regional sustainable development,though modern market economy treats them mainly as economic units less valuable for incomes than industrial.A new look at TTNU may be supported by their ecologicaleconomic assessment.A case study in the coastal Nenets TTNU belonging to family-clan community‘Ya’Erv’demonstrates its possible input to local sustainable development.

关键词： Indigenous peoples Russian Arctic traditional nature management ecosystem services value sustainable development Ice Silk Road

Elucidating elusive quaternary selenide EuCeCuSe3:Synthesis,crystal structure,properties and theoretical studies

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Journal of Rare Earths 2024年第1期42卷 163-171,I0006页

作者： Maxim v.Grigoriev Anna v.Ruseikina Maxim S.Molokeev vladimir A.Chernyshev Aleksandr S.Aleksandrovsky alexander S.Krylov Svetlana N.Krylova Nikolai P.Shestakov Dmitriy A.velikanov alexander A.Garmonov Alexey v.Matigorov Evgeny A.Ostapchuk Thomas Schleid Damir A.Safin Laboratory of Theory and Optimization of Chemical and Technological Processes University of TyumenVolodarskogo Str.6625003TyumenRussian Federation Kirensky Institute of Physics Federal Research Center KSC SB RASAkademgorodok 50 Bld.38660036KrasnoyarskRussian Federation Department of Physics Far Eastern State Transport UniversitySerysheva Str.47680021KrasnoyarskRussian Federation Institute of Natural Sciences and Mathematics Ural Federal University Named After the First President of Russia B.N.YeltsinMira Str.19620002EkaterinburgRussian Federation Department of Photonics and Laser Technology Siberian Federal UniversitySvobodnii Ave.79660079KrasnoyarskRussian Federation Institute of Physics and Technology University of TyumenVolodarskogo Str.6625003 TyumenRussian Federation Institute for Inorganic Chemistry University of StuttgartPfaffenwaldring 55D-70569StuttgartGermany Scientific and Educational and Innovation Center for Chemical and Pharmaceutical Technologies Ural Federal University named after the First President of Russia B.N.YeltsinMira Str.19620002 EkaterinburgRussian Federation University of Tyumen Volodarskogo Str.6625003TyumenRussian Federation

We report on the novel heterometallic quaternary selenide EuCeCuSe3,the fabrication of which has been a challenge until this *** structure of the reported selenide was elucidated from the powder X-ray diffraction data,which revealed the formation of EuCeCuSe3with excellent yield(96.7%)accompanied with a minor fraction of CeSe2(3.3%),and was best solved in orthorhombic space group Pnma with the BaLaCuS3structural ***,the crystal structure of the title compound completes the row of the heterometallic quaternary selenides EuRECuSe3(RE=La,Pr,Nd,Sm,Eu,Gd,Tb,Dy,Ho,Er,Tm,Yb,Lu,Y),of which the cerium-based derivative exclusively belongs to the BaLaCuS3structural *** distortion of the CuSe4polyhedron was compared for the whole series of EuRECuSe3compounds using theτ4-descriptor for four coordinated ions,which revealed the highest degree of distortion for the Ce3+-containing selenide,followed by the La3+-based ***,the crystallographic and geometrical parameters of the reported selenide were discussed in comparison to the Ce3+-based sulfides SrCeCuS3and *** initio calculations of the crystal structure,a phonon spectrum and elastic constants for the crystal of EuCeCuSe3were also *** types and wavenumbers of fundame ntal modes were determined and the involvement of ions participating in the phonon modes was *** experimental IR spectrum of the reported selenide was interpreted and found to be in agreement with the calculated *** experimental direct band gap of EuCeCuSe3was measured to be 1.36 ev that is consistent with the concept of its origin due to interband transitions between orbitals emerging mainly from 4f(valence band)and 5d(conduction band)levels of the Eu2+*** dependence of the Young’s modulus on the direction demonstrates the anisotropy of the elastic properties,while the vickers hardness for EuCeCuSe3was calculated to be 5.2 ***,the title compound is paramagnetic above 4 K.

关键词： Quaternary selenide Synthesis Crystal structure Ab initio calculations Magnetic measurements Spectroscopy