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Arylazopyrazole-functionalized photoswitchable octanuclear Zn(Ⅱ)-silsesquioxane nanocage

Science China Chemistry 2021年第3期64卷 419-425页

作者： Kai Sheng Ya-Nan Liu rakesh kumar gupta Mohamedally Kurmoo Di Sun School of Aeronautics Shandong Jiaotong UniversityJi'nan 250037China School of Chemistry and Chemical Engineering State Key Laboratory of Crystal MaterialsShandong UniversityJi'nan 250100China Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology School of Chemistry and Chemical Engineering厶iaocheng UniversityLiaocheng 252000China Institut de Chimie de Strasbourg Universite de StrasbourgCNRS-L/MR 71774 rue Blaise PascalStrasbourg Cedex 67008France

Photoswitchable organic materials have shown significant advancement for photonic applications,however,the polynuclear metal clusters conjugated with photoswitching properties are still ***,a novel octanuclear Zn(Ⅱ) nanocage{[Zn_(8)-(Me_(4)Si_(4)O_(8))_(2)(azopz)_(8)]·4CH_(2)Cl_(2)·MeOH·MeCN}(SD/Zn8)(Hazopz=3,5-dimethyl-4-(phenyldiazenyl)-1H-pyrazole),based on multidentate silsesquioxane and pyrazole modified by photoisomerizable azo group has been designed and synthesized to realize the reversible photoswitching behavior.X-ray crystallographic study reveals that the unique metal core consists of two annular Me_(4)Si_(4)O_(8)^(4-)sandwiching a ring of eight Zn atoms where the pyrazole end of azopz-bridges them *** azopz-ligands diverge above and below the plane defined by eight Zn ***,SD/Zn8 shows quick trans-to-cis transformation upon 365 nm light irradiation,which can be easily changed back by 450 nm light,but slow cis-to-trans reversibility at room temperature as confirmed by UV-V is and 1H NMR *** process,which presumably regulates the spaces,acts like a pump and is completely *** such,it can be considered as a molecular pump energized by ***,the molecule is an energy reservoir where it absorbs the light energy and releases it slowly with time.

关键词： silsesquioxane metal-organic nanocage photochromism X-ray single-crystal structure

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Synthesis,Structure,and Optical-response Magnetic Property of a Heteroarene-azo Functionalized Mn_(19) Cluster

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中国化学:英文版 2023年第14期41卷 1667-1672页

作者： Yongkai Deng Yingying Wu Zhaoyang Li Zvonko Jagličić rakesh kumar gupta Chenho Tung Di Sun Key Lab of Colloid and Interface Chemistry Ministry of EducationSchool of Chemistry and Chemical EngineeringShandong UniversityJinanShandong250100 China School of Materials Science and Engineering Nankai University38 Tongyan RoadHaihe Educational ParkTianjin300350 China Institute of Mathematics Physics and Mechanics&Faculty of Civil and Geodetic EngineeringUniversity of Ljubljana1000 LjubljanaSlovenia

Metal clusters with photoswitching ligands can undergo magnetic changes under light radiation,which makes them potential optical-response magnetic-switching ***,a photoswitchable Mn-oxo cluster[Mn^(II)_(15)Mn^(III)_(4)(L)_(18)(OH)_(12)(N_(3))_(6)](ClO_(4))_(2)(C_(6)H_(5)CN)_(8),(Mn19azo,HL=1-(hydroxymethyl)-3,5-dimethyl-4-(phenyldiazenyl)-pyrazole)has been designed and synthesized to realize the photoswitching ***19azo shows quick trans-to-cis transformation upon 365 nm light irradiation in CH2Cl2 solution and solid state as confirmed by UV-Vis *** the powder sample was irradiated for 80 min,the Curie constant of Mn19azo increases by about 7%.The change of magnetic properties can be considered as the result of the change of intermolecular interactions.

关键词： Crystalstructure Cluster compounds Photochromism Magnetic properties Stimuli-responsive molecular magnet

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Temperature-induced Sn(Ⅱ) supramolecular isomeric frameworks as promising heterogeneous catalysts for cyanosilylation of aldehydes

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Science China Chemistry 2020年第2期63卷 182-186页

作者： Kai Sheng Li-Ming Fan Xue-Fei Tian rakesh kumar gupta Linna Gao Chen-Ho Tung Di Sun Key Laboratory of Colloid and Interface Chemistry Ministry of EducationSchool of Chemistry and Chemical EngineeringState Key Laboratory of Crystal MaterialsShandong UniversityJinan 250100China School of Aeronautics Shandong Jiaotong UniversityJinan 250037China Department of Chemistry College of ScienceNorth University of ChinaTaiyuan 030051China College of Chemical and Environmental Engineering Shandong University of Science and TechnologyQingdao 266590China

Two novel Sn(Ⅱ) supramolecular isomeric frameworks,with the identical formula of {(NH2Me2)2[Sn(BDC)(SO4)]}n,Sn-CP-1-α(1) and Sn-CP-1-β(2)(H2BDC=terephthalic acid) were synthesized under solvothermal condition and fully characterized by single crystal X-ray diffraction(SCXRD),Fourier transform infrared spectroscopy(FTIR),ultraviolet-visible spectroscopy(UVVis),elemental analyses,and thermogravimetric analysis(TGA).Interestingly,the structures of 1 and 2 are governed by the temperature of the reaction,suggesting a temperature-induced supramolecular *** supramolecular isomers are primarily caused by the different bridging alignments of SO42–.Compounds 1 and 2 display 2 D layer and 3 D framework with different topologies,non-interpenetrated 44-sql and two-fold interpenetrated 4-connected dia topology,*** to Lewis acid properties of coordinatively unsaturated Sn(Ⅱ) sites in CPs,they have been utilized as heterogeneous catalyst for the cyanosilylation of aldehydes with an excellent conversion yield over 99% under solvent-free conditions.

关键词： supramolecular isomerism Sn(Ⅱ)coordination polymers catalysis cyanosilylation

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A novel 58-nuclei silver nanowheel encapsulating a subvalent Ag64+ kernel

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Science China Chemistry 2020年第1期63卷 16-20页

作者： Zhi Wang Qing-Ping Qu Hai-Feng Su Peng Huang rakesh kumar gupta Qing-Yun Liu Chen-Ho Tung Di Sun Lan-Sun Zheng Key Laboratory of Colloid and Interface Chemistry Ministry of EducationSchool of Chemistry and Chemical EngineeringState Key Laboratory of Crystal MaterialsShandong UniversityJinan 250100China Jiangsu Key Laboratory of Green Synthetic Chemistry for Functional Materials Department of ChemistrySchool of Chemistry and Chemical EngineeringJiangsu Normal UniversityXuzhou 221116China State Key Laboratory for Physical Chemistry of Solid Surfaces and Department of Chemistry College of Chemistry and Chemical EngineeringXiamen UniversityXiamen 361005China College of Chemical and Environmental Engineering Shandong University of Science and TechnologyQingdao 266590China

The combination of CrO4^2-anion and N,N′-dimethylformamide(DMF)-containing solvent helps to stabilize an atom-precise ultrasmall Ag6 kernel into a 52-nuclei silver shell,giving a core-shell Ag6@Ag52 wheel-like struct... 详细信息

关键词： silver cluster subvalent Ag6^4+kernel electrospray ionisation mass spectrometry(ESI-MS) photocurrent response

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Surface Modification Aspects for Improving Biomedical Properties in Implants:A Review

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 213-241页

作者： J.Sharath kumar rakesh kumar Rajeev Verma Industrial and Production Department Dr B R Ambedkar National Institute of Technology JalandharJalandharPunjab144008India

The primary focus during surgery is to ensure successful implantation by achieving long-term and stable fixation of *** surgery is now more focused on the development of novel biomaterials intended to improve implant *** obtain a better understanding of metal implants,this article investigated the causes of material failures in certain cases and analysed a few case *** interaction between the implant and bone tissue was a crucial aspect of successful implantation,and this study explored the factors influencing this interaction as well as ways to improve *** modern approaches used for modifying implant surfaces were systematically illustrated and briefly *** spray coatings were often favoured because of their wide range of coating materials,but other substantial surface modifications(such as friction stir processing and laser surface texturing)were also used for a selection of ***,implant surfaces with desirable features,such as biocompatibility,antibacterial properties,corrosion resistance,and wear resistance,were essential for optimising implant *** systematic review's main aim is to provide exhaustive reference information and a broad overview to advance the production and design of orthopaedic implants.

关键词： Biomaterials Surface treatments Thermal spray coatings Antibacterial Biocompatibility Corrosion resistance Wear resistance

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Facile one-pot synthesis of a novel all-carbon stair containing dimerized pentalene core from alkyne

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Chinese Chemical Letters 2022年第4期33卷 2047-2051页

作者： Hui Zhao rakesh kumar gupta Wei Zhang Jiong Jia Qun Yu Zhiyong Gao Guilin Zhuang Dacheng Li Xingpo Wang Chen Ho Tung Di Sun Key Laboratory of Colloid and Interface Chemistry Ministry of EducationSchool of Chemistry and Chemical EngineeringState Key Laboratory of Crystal MaterialsShandong UniversityJi’nan 250100China College of Chemical Engineering and Materials Science Zhejiang University of TechnologyHangzhou 310032China School of Chemistry and Chemical Engineering Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine ChemicalsKey Laboratory of Green Chemical Media and ReactionsMinistry of EducationHenan Normal UniversityXinxiang 453007China Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology and School of Chemistry and Chemical EngineeringLiaocheng UniversityLiaocheng 252000China

The construction of all-carbon molecule frameworks remains challenging. Herein, we report a facile and efficient one-pot synthesis of a novel all-carbon stair containing dimerized pentalene core using inexpensive cyclopropyl alkyne catalyzed by in situ generated Cu(I) from the comproportionation reaction of Cu(II) salt and Cu powder under mild reaction conditions. The reaction proceeds via sequential acetylenic coupling, followed by cyclization and [2 + 2] cycloaddition to directly produce pentalene dimer, which is difficult to access by other established methods. Different mechanistic paths were studied for the pentalene formation using density functional theory, suggesting that the reaction also proceeds through acetylenic coupling followed by cyclization and [2 + 2] cycloaddition. Based on the activation energy barriers, Path 1 has the rate-determining step of 38.63 kcal/mol, which is the most thermodynamically preferred one among the four paths.

关键词： One-pot synthesis Penatlene dimerization Comproportionation reaction Crystal structure Theoretical calculations

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Locking plates in distal humerus fractures： study of 43 patients

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Chinese Journal of Traumatology 2013年第4期16卷 207-211页

作者： rakesh kumar gupta Vinay gupta Dickey Richard Marak Department of Orthopaedics Physical MedicineParaplegia and Rehabilitation Pt. BD Sharma Post Gradu-ate Institute of Medical Sciences Rohtak 124001 India Clinical Associate Department of Orthopaedics FortisHealthcare Mohali Ludhiana Punjab 141002 India

Objective： The treatment of multi- fragmentary, intraarticular fractures of the distal humerus is difficult, even in young patients with bone of good quality. Small distal fragment, diminished bone mineral quality and increased trauma-associated joint destruction make stable joint reconstruction more problematic. The anatomically preshaped locking plates allow angular stable fixation for these complex fractures. We evaluated functional results of patients treated with open reduction and internal fixation with distal humerus locking plates for complex distal hu- merus fractures. Methods： Forty-three consecutive patients with ar- ticular fractures of the distal humerus were treated by open reduction and internal fixation with AO distal humerus plate system and locking reconstruction plates. Forty patients were available for the final outcome analysis. According to AO/ASIF classification, there were 2 cases of type A2, 4 cases of type A3, 1 case of type B1, 1 case of type B2, 14 cases of type C1, 7 cases of type C2 and 11 cases of type C3. Open reduction with triceps splitting technique was used in all patients. The clinical and radiographic follow-up was performed and outcome measures included pain assessment,range of motion, and Mayo elbow performance score. Results： Forty patients were available for the final outcome analysis. There were 29 males and 11 females with an average age of 38.4 years （18-73 years）. Clinical and ra- diological consolidation of the fracture was observed in all cases at an average of 11.6 weeks （9-14 weeks）. The average follow-up was 12 months （10-18 months）. Using the Mayo elbow performance score the results obtained were graded as excellent or good results in 33 patients （82.5%）. One pa- tient had superficial infection, and 4 had myositis ossificans. There were no cases of primary malposition or secondary displacement, implant failure or ulnar neuropathy. Conclusion： Anatomically preshaped distal humerus locking plate system is useful i

关键词： Humerus Fractures, bone Bone plates Fracture fixation, internal

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Critical Review on Balanites aegyptiaca Delile:Phytoconstituents,Pharmacological Properties and Nanointerventions

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Chinese Journal of Integrative Medicine 2024年第7期30卷 653-663页

作者： Surendra kumar Gautam rakesh kumar Paul Devesh M.Sawant Amita Sarwal Kaisar Raza Department of Pharmacy School of Chemical Sciences and PharmacyCentral University of RajasthanBandarsindriAjmerRajasthan305817India University Institute of Pharmaceutical Sciences Panjab UniversityChandigarh160014India

Balanites aegyptiaca Delile(BA)is an enduring xerophytic woody and spinous flowering tree and is commonly known as desert date or Ingudi(Hingot).It belongs to the family Zygophyllaceae,which is specific to be drought areas of Nigeria,Africa,South Asia and India(Rajasthan).In Ayurveda,this traditional medicinal plant is reported for the management of jaundice,syphilis,yellow fever,metabolic disorders,liver,and spleen *** main aim of the review is to compile its medicinal uses and further advancements to showcase the promises inherited in various parts of the plant for the benefit of *** per the literature survey,various researchers have focused on the detailed investigation of BA including the phytopharmacological evidence,chemical constituents,nano-formulations,commercialized products,and clinical *** remarkable scaffolds and isolated compounds like diosgenin,yamogenin,balanitin1/2,balanitin 3,bal4/5,bal6/7,rutin-3-glycosides,3,7-diglycosides,(3,12,14,16)–(12-hydroxycholest-5-ene-3,16-diyl-bis)-D-glucopyranoside and balanitoside have been ***,this traditional plant has been scientifically proven by in vitro and in *** on the complete review of this plant,most of the compounds have been isolated from the fruit and kernel ***,based on the literature,a histogram was developed for pharmacological activity in which antidiabetic study was found to be more compared to other pharmacological *** a spinous desert dates,this plant needs to be explored more to bring out newer phytochemicals in the management of various diseases.

关键词： Delile desert date phytochemicals nano-phytopharmaceutical pharmacological activities traditional medicine

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Trigonometric tension B-spline collocation approximations for time fractional Burgers’equation

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Journal of Ocean Engineering and Science 2024年第5期9卷 508-516页

作者： Brajesh kumar Singh Mukesh gupta School of Physical and Decision Sciences Department of MathematicsBabasaheb Bhimrao Ambedkar University Lucknow 226025(UP)INDIA

This manuscript’s aim is to form and examine the numerical simulation of Caputo-time fractional nonlinear Burgers’equation via collocation approach with trigonometric tension B-splines as base ***,L 1 discretization formula is utilized for the time fractional derivative and after linearizing the nonlinear term,the trigonometric tension B-spline interpolants are utilized to get a system of simultaneous linear equations that are solved via Gauss elimination ***,numerical approximation at the desired time level is *** is demonstrated via von-Neumann approach that proposed scheme produces stable *** results of six different test examples having their analytical solutions are compared with the results in the literature to validate the accuracy and efficiency of the scheme.

关键词： Fractional Burgers’equation Trigonometric tension B-spline Collocation scheme Gauss elimination method

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A Novel Multi-objective Protection Coordination Scheme for a Microgrid with Optimal Deployment of Dual-setting ROCOV Based Relays

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Protection and Control of Modern Power Systems 2024年第4期9卷 23-38页

作者： Praveen kumar gupta Priyanshul Niranjan Niraj kumar Choudhary Nitin Singh Ravindra kumar Singh the Department of Electrical Engineering Motilal Nehru National Institute of Technology AllahabadPrayagraj 211004India

Relay coordination is crucial in electrical power systems to protect against malfunctions and damage caused by unexpected events like short *** address the challenge associated with the reverse direction of fault current,dual-setting(DS)directional over-current relays have evolved but failed to provide proper coordination during changes of load,generation,and *** the meantime,with the increasing number of DS relays,the total relay operating time tends to ***,this paper proposes a protection scheme based on the optimal deployment of conventional and dual-setting rate of change of voltage(DS-ROCOV)relays in distribution *** holds true for varying network topologies and is unaffected by variations in load and *** objective of the proposed scheme is to ensure reliable and efficient protection against faults in distribution systems by minimizing the overall operating time with the optimal number of DS-ROCOV *** proposed protection scheme’s performance is evaluated for different coordination time interval values as well as in different microgrid *** paper outlines the design and implementation of the proposed protection scheme which is validated on the modified IEEE 14-bus system using simulations in Matlab/Simulink.

关键词： Coordination time interval DS-ROCOV relay multi-objective optimization optimal-deployment protection coordination

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