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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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Chinese Journal of Chemistry 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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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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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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Intricacies during pregnancy with gestational diabetes mellitus

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World Journal of Clinical Cases 2025年第1期13卷 62-64页

作者： Richa Rattan Rimesh Pal Parul Chawla gupta Arvind kumar Morya Ripunjay Prasad Department of Endocrinology Post Graduate Institute of Medical Education and ResearchChandigarh 160012India Department of Ophthalmology Post Graduate Institute of Medical Education and ResearchChandigarh 160012PunjabIndia Department of Ophthalmology All India Institute of Medical SciencesHyderabad 508126TelanganaIndia Department of Ophthalmology RP Eye InstituteDelhi 110001India

The study by Cao et al aimed to identify early second-trimester biomarkers that could predict gestational diabetes mellitus(GDM)development using advanced proteomic techniques,such as Isobaric tags for relative and absolute quantitation isobaric tags for relative and absolute quantitation and liquid chromatography-mass spectrometry liquid chromatography-mass *** analysis revealed 47 differentially expressed proteins in the GDM group,with retinol-binding protein 4 and angiopoietin-like 8 showing significantly elevated serum levels compared to *** these findings are promising,the study is limited by its small sample size(n=4 per group)and lacks essential details on the reproducibility and reliability of the protein quantification methods ***,the absence of experimental validation weakens the interpretation of the protein-protein interaction network identified through bioinformatics *** study's focus on second-trimester biomarkers raises concerns about whether this is a sufficiently early period to implement preventive interventions for *** GDM risk during the first trimester or pre-conceptional period may offer more clinical *** its limitations,the study presents valuable insights into potential GDM biomarkers,but larger,well-validated studies are needed to establish their predictive utility and generalizability.

关键词： Gestational diabetes mellitus Biomarkers Differentially expressed proteins Retinol-binding protein 4 Angiopoietin-like 8 Proteomics Lifestyle interventions Early prediction

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Blumgart's technique of pancreaticojejunostomy: Analysis of safety and outcomes

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Hepatobiliary & Pancreatic Diseases International 2019年第2期18卷 181-187页

作者： Vishal gupta Saket kumar Vivek gupta Pradeep Joshi Rahul Rahul rakesh kumar Yadav Amit Dangi Abhijit Chandra Department of Surgical Gastroenterology King George's Medical University Department of Human Organ Transplant King George's Medical University

Background: Blumgart's pancreaticojejunostomy(PJ) has been described with low pancreatic leak rates. This study aimed to evaluate our experience with this technique regarding the pancreatic leak and other perioperative outcomes. Methods: We performed a single-center retrospective analysis of a cohort of 81 patients who underwent pancreaticoduodenectomy in our department from January 2011 to February 2018. The primary endpoint was the occurrence of a clinically relevant postoperative pancreatic fistula(CR-POPF) and analysis of its risk factors. Results: The CR-POPF rate was 12.3%. Fistula risk score(FRS) was the only significant risk factor for the occurrence of overall POPF in multivariate analysis. However, none of the other factors including FRS was found to be significantly associated with CR-POPF risk. A strong positive correlation was found between the CR-POPF and the incidence of delayed gastric emptying, post-pancreatectomy hemorrhage and increased length of hospital stay. Conclusion: Blumgart's technique is a safe technique of pancreatico-enteric anastomosis with low rates of CR-POPF. CR-POPF with this technique is independent of most of the preoperative and intraoperative factors. Therefore, this technique can be used for all types of the pancreas with consistently good results.

关键词： Pancreaticoduodenectomy Pancreatico-jejunal anastomosis Postoperative pancreatic fistula Pancreatic leak

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Analysis of Age Dependent Effects of Heat Stress on EEG Frequency Components in Rats

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Biomedical and Environmental Sciences 2009年第2期22卷 141-150页

作者： rakesh kumar SINHA Department of Biomedical Instrumentation Birla Institute of Technology

Objective To demonstrate changes in different frequencies of cerebral electrical activity or electroencephalogram （EEG） following exposure to high environmental heat in three different age groups of freely moving rats. Methods Rats were divided into three groups （i） acute heat stress - subjected to a single exposure for four hours at 38 ℃; （ii） chronic heat stress exposed for 21 days daily for one hour at 38 ℃, and （iii） handling control groups. The digital polygraphic sleep-EEG recordings were performed just after the heat exposure from acute stressed rats and on 22nd day from chronic stressed rats by simultaneous recording of cortical EEG, EOG （electrooculogram）, and EMG （electromyogram）. Further, power spectrum analyses were performed to analyze the effects of heat stress. Results The frequency analysis of EEG signals following exposure to high environmental heat revealed that in all three age groups of rats, changes in higher frequency components （β2） were significant in all sleep-wake states following both acute and chronic heat stress conditions. After exposure to acute heat, significant changes in EEG frequencies with respect to their control groups were observed, which were reversed partly or fully in four hours of EEG recording. On the other hand, due to repetitive chronic exposure to hot environment, adaptive and long-term changes in EEG frequency patterns were observed. Conclusion The present study has exhibited that the cortical EEG is sensitive to environmental heat and alterations in EEG frequencies in different sleep-wake states due to heat stress can be differentiated efficiently by EEG power spectrum analysis.

关键词： Electroencephalogram Heat stress Power spectrum Sleep Rats

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A Key Management Scheme Using(p,q)-Lucas Polynomials in Wireless Sensor Network

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China Communications 2021年第11期18卷 210-228页

作者： Amit kumar Gautam rakesh kumar Madan Mohan Malaviya University of Technology Gorakhpur-273001India

Wireless Sensor Network(WSN)has witnessed an unpredictable growth for the last few *** has many applications in various critical sectors such as real-time monitoring of nuclear power plant,disaster management,environment,military area ***,due to the distributed and remote deployment of sensor nodes in such networks,they are highly vulnerable to different security *** sensor network always needs a proficient key management scheme to secure data because of resourceconstrained *** polynomial based key management schemes are simple,but the computational complexity is a big *** polynomials,Fibonacci polynomials,Chebychev polynomials are used in Engineering,Physics,Combinatory and Numerical analysis *** this paper,we propose a key management scheme using(p,q)-Lucas polynomial to improve the security of ***(p,q)-Lucas polynomial,p represents a random base number while q represents a substitute value of x in the *** value of p is unique,and q is different according to communication between *** of the proposed method on several parameters such as computational overhead,efficiency and storage cost have been performed and compared with existing related *** analysis demonstrates that the proposed(p,q)-Lucas polynomial based key management scheme outperforms over other polynomials in terms of the number of keys used and efficiency.

关键词： key management lucas polynomial WSN security pairwise key distribution key generation hierarchical key management

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