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Recent advances on the synthesis and application of tetrahydro-γ-carbolines

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Chinese Chemical Letters 2023年第12期34卷 119-136页

作者： Haibo Mei klára Aradi loránd k.ss Jianlin Han Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources Nanjing Forestry University Institute of Organic Chemistry Research Centre for Natural Sciences Stereochemistry Research Group

Tetrahydro-γ-carbolines(THγ Cs) constitute one of the most important subtypes of indole alkaloids. In addition to being substructures of natural products, these structural motifs and moieties can often be found in pharmaceuticals due to their diverse bioactivities such as antiviral, antibacterial, antifungal,antiparasitic, antitumor, anti-inflammatory, and neuropharmacological activities. Beyond the pharmacological and biological aspects of these scaffolds, they have considerable synthetic applications for the construction of further bioactive compounds, too. The aim of this review is to summarize recent developments in the synthesis of this compound class.

关键词： Tetrahydro-γ -carbolines Synthetic methods Bioactive molecuels Asymmetric synthesis Indole Polycyclic compounds

Microstructure transformations and improving wear resistance of austenitic stainless steel additively fabricated by arc-based DED process

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Defence Technology（防务技术） 2024年第8期38卷 194-204页

作者： Ashish Yadav Manu Srivastava Prashant k.Jain Sandeep Rathee Hybrid Additive Manufacturing Laboratory Mechanical Engineering DepartmentPDPM Indian Institute of Information TechnologyDesign&ManufacturingJabalpur482005Madhya PradeshIndia FFF Laboratory Mechanical Engineering DepartmentPDPM Indian Institute of Information TechnologyDesign&ManufacturingJabalpur482005Madhya PradeshIndia Department of Mechanical Engineering National Institute of TechnologySrinagarIndia

In this study, austenitic stainless steel(Ass) was additively fabricated by an arc-based direct energy deposition(DED) technique. Macrostructure, microstructure, mechanical characteristics at different spatial orientations(0°, 90°, and 45°), and wear characteristics were evaluated at the deposited structure top, middle, and bottom regions. Results show that austenite(γ) and delta-ferrite(δ) phases make up most of the microstructure of additively fabricated ss316LSi steel. Within γ matrix, δ phase is dispersed both(within and along) grain boundaries, exhibiting a fine vermicular morphology. The bottom, middle,and top regions of WAAM deposited Ass exhibit similar values to those of wrought ss316L in the tensile and impact test findings. Notably, a drop in hardness values is observed as build height increases. During SEM examinations of fractured surfaces from tensile specimen, closed dimples were observed, indicating good ductility of as-built structure. Wear test findings show signs of mild oxidation and usual adhesive wear. By depositing a mechanically mixed composite layer, an increase in the oxidation percentage was discovered to facilitate healing of worn surfaces. The findings of this study will help in design, production and renovation of products/components that are prone to wear. WAAM-deposited Ass has remarkable strength and ability to withstand impacts;it can be used in the production of armour plates for defence applications, mainly military vehicles and aircraft.

关键词： Metal additive deposition Defence applications Arc-based DED Characterization Wear behaviour Fractography

Crystal structure and luminescence dynamics of highly pure LiM(PO_(3))_(3):Eu^(3+)(M=Sr,Ca) red phosphors for white light emitting diodes

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Journal of Rare Earths 2024年第8期42卷 1470-1478,I0002页

作者： Payal khajuria M.Manhas A.k.Bedyal Ankush Vij H.C.Swart Vinay kumar Department of Physics and Astronomical Sciences Central University of JammuRahy-Suchani.Samba1143J&KIndia Department of Physics School of SciencesCluster University of JammuCanal RoadJammu180001India Department of Physics University of Petroleum and Energy StudiesDehradunUttarakhand248007India Department of Physics University of the Free StatePO.Box 339BloemfonteinZA 9300South Africa

Highly pure red phosphors LiM(PO_(3))_(3):Eu^(3+)(M=Sr,Ca) doped with Eu^(3+)(1 mol%) were synthesized via solution combustion method and their crystal structure and luminescence dynamics were studied to explore its suitability in white light emitting *** Rietveld refinement analysis of the powder Xray diffraction patterns reveals that the phosphors belong to the pure triclinic phase of LiSr(PO_(3))_(3) and LiCa(PO_(3)) with space group P-1(2).The scanning electron microscopy images showed the agglomerated *** photoluminescence emission spectra under 393 nm show an orange band at 594 nm and a red band at 613 nm ascribed to ^(5)D_(0)→^(7)F_(1).^(5)D_(0)→^(7)F_(2) transitions of Eu^(3+)ion in both the ***,the spectroscopic properties such as luminescence behaviour,and Stark splitting were used to examine the symmetry of Eu^(3+)ions in LiM(PO_(3))_(3):Es^(3+)(M=Sr,Ca) phosphors in terms of distortion induced upon *** Stark splitting shows that the actual site symmetry for Eu^(3+)ion was estimated to be D_(2) type for both *** photometric properties of LiCa(PO_(3))_(3):Eu^(3+)such as Commission International de l'Eclairage coordinates(x=0.64,y=0.36) near to the standard one(red),high color purity(95%) and higher brightness reveal that the phosphor has the capability of acting as a red component in n-UV white light emitting diodes.

关键词： Photoluminescence Phosphate WLEDs Stark splitting Rare earths

粉末冶金Al-5.6Zn-2Mg合金在热压缩过程中加工硬化特性及本构模型的比较

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Journal of Central South University 2024年第2期31卷 346-368页

作者： kATIkA Harikrishna DAMODA R.k. DAVIDSON M.J. SEETHARAM R. kASAGANI Veera Venkata Nagaraju Department of Mechanical Engineering National Institute of TechnologyWarangal 506004India Department of Mechanical Engineering The Indian Institute of Information Technology Design and ManufacturingKurnool 518007India

在300~5000℃、应变速率为0.1~0.0001 s−1的条件下,在万能试验机上对Al-5.6Zn-2Mg铝合金进行热压缩试验,以确定动态再结晶开始时的加工硬化速率曲线σ_(c)(ε_(c))l以及关键特征σ_(c)(ε_(c))l、σ_(p)(ε_(p))和σ_(ss)与Z系数之间的... 详细信息

在300~5000℃、应变速率为0.1~0.0001 s−1的条件下,在万能试验机上对Al-5.6Zn-2Mg铝合金进行热压缩试验,以确定动态再结晶开始时的加工硬化速率曲线σ_(c)(ε_(c))l以及关键特征σ_(c)(ε_(c))l、σ_(p)(ε_(p))和σ_(ss)与Z系数之间的相关性。使用了四个本构模型,Arrhenius模型、改进的Johnson-Cook模型(MJC)、改进的Zerilli-Armstrong模型(MZA)和开发的人工神经网络(ANN)。结果表明,ANN型模型和Arrhenius模型的相对误差的绝对平均值最低,分别为0.486%和3.36%,MZA型模型和MJC型模型的相对误差的绝对平均值较高,分别为8.84%和3.93%。由于Arrhenius模型能够处理各种因素之间的非线性关系,因此它被认为是最合适的预测模型,但在材料性质未知或实验数据有限的情况下,MJC模型可能是一种更简单的替代方法。MZA模型不适合估计热压缩时的流变应力。此外,训练最好的神经网络模型的预测性能最好,相对误差的绝对平均值为0.486%,R值为0.99。

关键词：加工硬化速率曲线本构建模热压缩 EBSD分析流变曲线

The Soft X-ray Imager(SXI)on the SMILE Mission

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Earth and Planetary Physics 2024年第1期8卷 5-14页

作者： S.Sembay A.L.Alme D.Agnolon T.Arnold A.Beardmore A.Belén Balado Margeli C.Bicknell C.Bouldin G.Branduardi-Raymont T.Crawford J.P.Breuer T.Buggey G.Butcher R.Canchal J.A.Carter A.Cheney Y.Collado-Vega H.Connor T.Crawford N.Eaton C.Feldman C.Forsyth T.Frantzen G.Galgóczi J.Garcia G.Y.Genov C.Gordillo H-P.Gröbelbauer M.Guedel Y.Guo M.Hailey D.Hall R.Hampson J.Hasiba O.Hetherington A.Holland S-Y.Hsieh M.W.J.Hubbard H.Jeszenszky M.Jones T.kennedy k.koch-Mehrin S.kögl S.krucker k.D.kuntz C.Lakin G.Laky O.Lylund A.Martindale J.Miguel Mas Hesse R.Nakamura k.Oksavik N.Østgaard H.Ottacher R.Ottensamer C.Pagani S.Parsons P.Patel J.Pearson G.Peikert F.S.Porter T.Pouliantis B.H.Qureshi W.Raab G.Randal A.M.Read N.M.M.Roque M.E.Rostad C.Runciman S.Sachdev A.Samsonov M.Soman D.Sibeck S.Smit J.Søndergaard R.Speight S.Stavland M.Steller TianRan Sun J.Thornhill W.Thomas k.Ullaland B.Walsh D.Walton C.Wang S.Yang School of Physics and Astronomy University of LeicesterLeicesterLE17RHUK Space Park Leicester University of LeicesterLeicesterLE17RHUK Mullard Space Science Laboratory University College LondonDorkingRH56NTUK Centre for Electronic Imaging Open UniversityMilton KeynesMK76 AAUK Birkeland Centre for Space Science Department of Physics and TechnologyUniv.of BergenN-5007 BergenNorway University of Vienna A-1010 ViennaAustria Space Research Institute Austrian Academy of SciencesA-8042 GrazAustria National Institute of Aerospace Technology MadridSpain ESTEC European Space Agency2201 AZ NoordwijkNetherlands State key Laboratory of Space Weather National Space Science CentreBeijing 100190China University of Applied Sciences and Arts Northwestern Switzerland CH-5210 WindischSwitzerland koegl Space GmbH CH-8157 DielsdorfSwitzerland Space Acoustics GmbH CH-8157 DielsdorfSwitzerland Zurich University of Applied Sciences 8400 WinterhurSwitzerland Genov Solutions N-5172 LoddefjordNorway STM Engineering N-5165 LaksevagNorway John Hopkins University Applied Physics Laboratory MD 20723USA NASA/Goddard Space Flight Centre MD 20771USA Center for Space Physics Boston UniversityBostonMA 02215USA Department of Theoretical Physics and Astrophysics Masaryk University60177 BrnoCzech Republic Institute of Physics E¨otvo¨s Lor´and University1053 BudapestHungary Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100045China Centro de Astrobiologia(CAB) CSIC-INTAMadridSpain

The Soft X-ray Imager(SXI)is part of the scientific payload of the Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)*** is a joint science mission between the European Space Agency(ESA)and the Chinese Academy of Sciences(CAS)and is due for launch in *** is a compact X-ray telescope with a wide field-of-view(FOV)capable of encompassing large portions of Earth’s magnetosphere from the vantage point of the SMILE *** is sensitive to the soft X-rays produced by the Solar Wind Charge eXchange(SWCX)process produced when heavy ions of solar wind origin interact with neutral particles in Earth’s *** provides a mechanism for boundary detection within the magnetosphere,such as the position of Earth’s magnetopause,because the solar wind heavy ions have a very low density in regions of closed magnetic field *** sensitivity of the SXI is such that it can potentially track movements of the magnetopause on timescales of a few minutes and the orbit of SMILE will enable such movements to be tracked for segments lasting many *** is led by the University of Leicester in the United kingdom(Uk)with collaborating organisations on hardware,software and science support within the Uk,Europe,China and the United States.

关键词： Soft X-ray Imaging micropore optics large area CCD

Impact of Some Antibiotics on Bacteria Isolated from Appendices in kirkuk Province, Iraq

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Advances in Bioscience and Biotechnology 2018年第1期9卷 1-10页

作者： Ayoub A. Bazzaz Diyari A. k. lor Najdat B. Mahdi Department of Basic Science Faculty of Dentistry University of Kirkuk Kirkuk Iraq Department of Biology Faculty of Sciences University of Kirkuk Kirkuk Iraq

A bacteriological study of 50 appendectomy cases for patients diagnosed by physicians to be appendicitis, within kirkuk province was carried out to isolate the habitat bacteria of appendix and to assess the impact of some antibiotics on isolated bacterial species from the appendices. The age of patients ranged between 3 - 45 year old (21 male and 29 female). The culture results showed 94% single isolate with 2% negative growth and 4% mixed growth were obtained. The gram positive bacteria isolate formed (11.77%) less than gram negative (88.23%). The total isolates represented 51 included Escherichia coli 34 (66.66%), followed by Enterococcus faecalis 3 (5.89%), klebsiella pneumonia 3 (5.89%), Citrobacter youngae 2 (3.92%), Raultella terrigena 2 (3.92%), Pseudomonas aeruginosa 2 (3.92%), Enterrobacter cloacae 1 (1.96%), Serratia fonticola 1 (1.96%), Entercoccus faecium 1 (1.92%), Staphylococcus epidermides 1 (1.96%) and Staphylococcus xylosus 1 (1.96%). The Staphylococcus xylosus was the first time to be isolated in kirkuk city while both of Raultella terrigena and Citrobacter youngae were isolated for the first time in appendix samples. Only 16 various antibiotics were tested against Enterobacteriaceae and Pseudomonas aeruginosa while 12 and 7 against Staphylococcus sp. and Enterococcus sp., respectively. The Imipenem and Amikacin were found to be most effective antibiotics against all Enterobacteriaceae isolates and Pseudomonas aeruginosa while Ampicillin, Piperacillin, Ceftazidime, Augmentin, and Cephalothin were ineffective against all isolated bacteria. The Penicillin and Vancomycin were effective against gram positive bacteria.

关键词： Bacteria Antibiotics Appendix Appendectomy Iraq

The Qitai radio telescope

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Science China(Physics,Mechanics & Astronomy) 2023年第8期66卷 150-161页

作者： Na Wang Qian Xu Jun Ma Zhiyong Liu Qi Liu Hailong Zhang Xin Pei Maozheng Chen Richard N.Manchester kejia Lee Xingwu Zheng Hans J.kärcher Wulin Zhao Hongwei Li Dongwei Li Martin Süss Matthias Reichert Zhongyi Zhu Congsi Wang Mingshuai Li Rui Li Ning Li Guljaina kazezkhan Wenming Yan Gang Wu Lang Cui Ming Zhang Haitao Li Xinjiang Astronomical Observatory Chinese Academy of SciencesUrumqi 830011China key Laboratory of Radio Astronomy Chinese Academy of SciencesNanjing 210008China Xinjiang key Laboratory of Radio Astrophysics Urumqi 830011China Xinjiang key Laboratory of Microwave Technology Urumqi 830011China Australia Telescope National Facility CSIRO Space and AstronomyEpping 1710Australia Department of Astronomy Peking UniversityBejing 100871China School of Astronomy and Space Science Nanjing UniversityNanjing 210093China Dr.Hans Jirgen karcher Engineering Office Karben 61184Germany Northwest China Research Institute of Electronic Equipment Xi'an 710065China OHB Digital Connect(MT Mechatronics) Mainz 55130Germany Beijing Institute of Architetural Design Beijing 100045China Guangzhou Instiute of Technology Xidian UniversityGuangzhou 510555 China

This study presents a general outline of the Qitai radio telescope(QTT)***,the site of the telescope,is a county of Xinjiang Uygur Autonomous Region of China,located in the east Tianshan Mountains at an elevation of about 1800 *** QTT is a fully steerable,Gregorian-type telescope with a standard parabolic main reflector of 110 m *** QTT has adopted an umbrella support,homology-symmetric lightweight *** main reflector is active so that the deformation caused by gravity can be *** structural design aims to ultimately allow high-sensitivity observations from 150 MHz up to115 *** satisfy the requirements for early scientific goals,the QTTwill be equipped with ultra-wideband receivers and large field-of-view multi-beam receivers.A multi-function signal-processing system based on RFSo C and GPU processor chips will be *** will enable the QTT to operate in pulsar,spectral line,continuum and Very Long Baseline Interferometer(VLBI)observing *** compatibility(EMC)and radio frequency interference(RFI)control techniques are adopted throughout the system *** QTT will form a world-class observational platform for the detection of lowfrequency(nano Hertz)gravitational waves through pulsar timing array(PTA)techniques,pulsar surveys,the discovery of binary black-hole systems,and exploring dark matter and the origin of life in the *** QTT will also play an important role in improving the Chinese and international VLBI networks,allowing high-sensitivity and high-resolution observations of the nuclei of distant galaxies and gravitational lensing *** astrometric observations will also contribute to improving the accuracy of the celestial reference ***,the QTT will be able to support future space activities such as planetary exploration in the solar system and to contribute to the search for extraterrestrial intelligence.

关键词： radio telescope radio astronomy observation receiver RFI

Spatial distribution and impacts of climate change on Milicia excelsa in Benin,West Africa

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Journal of Forestry Research 2021年第1期32卷 143-150页

作者： Sunday Berlioz kakpo Augustin k.ssi Nounangnon Aoudji Denis Gnanguènon-Guéssè Alain Jaures Gbètoho kourouma koura Géoff roy kévin Djotan Jean Cossi Ganglo Laboratory of Forest Sciences Faculty of Agricultural SciencesUniversity of Abomey-CalaviBP 1493 Abomey-CalaviBenin

African teak(Milicia excelsa(Welw.)***)is an endangered multi-use *** the impact of climate change on the distribution of this species may improve the ability to anticipate or recognize its decline or expansion and to take appropriate conservation measures if *** niche modeling was projected in geographical space to study the current and future distribution of *** in Bé*** was used to estimate the potential geographic distribution of the species under two Representative Concentration Pathways(RCP).Miroc 5 summaries and two RCP 4.5 and RCP 8.5 scenarios were used as predictor variables for projections of the geographic potential of this *** performance of the model was assessed by the area under the curve(AUC),true skill statistics(Tss)and partial receiver operating characteristics(Partial ROC).From the results,*** was more a secondary species in the Guinean climatic zone and part of the Sudanian-Guinean and Sudanian climatic *** projections show a signifi cant decrease in suitable habitats for the species from the two RCP *** a part of the Guinean climatic zone remained suitable and few protected areas will conserve in situ *** the sustainable conservation of ***,it is essential to strengthen the protection of sacred forests located in the Guinean climatic zone.

关键词： Ecological niche modeling Climate change Milicia excelsa Benin West Africa

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滚动轴承寿命计算的新参数

国外铁道机车与动车 1986年第11期 34-39页

作者： H.k.lorsch A.kraus 韩才元

西德《驱动技术》杂志编者按:通过大量的研究工作,在滚动轴承领域内,不断获得新的知识,从而提出了下述新的参数。本文提出的该参数,第一次定量地说明了在DIN/ISO281标准中给出的系数 a23,最后举出了应用实例。

关键词：概率 DIN 清洁度轴承装置寿命计算